Bright, cheery colors, delicate textures, and you can eat them!
Edible flowers have been part of the human diet since, well, since there have been people! Did you know that carnation petals have been used as one of the ingredients in the French liqueur, Chartreuse, since the 17th century?
Before we start, let me first share a story from my early trials with edible flowers. My dear sister decided to marry an Australian sailor and asked me to make her wedding cake. It was a lovely tiered white cake with yellow borders. I decided to add some stunning yellow flowers I saw outside. My sister’s reaction of horror was not what I expected - until she explained that the Angel’s Trumpet flowers I used were extremely poisonous. Needless to say, the flowers and the frosting came off. So…
When in doubt, don’t
Before you go popping random blossoms in your mouth, you need to know that some flowers can make you sick, and others can kill you. If you are even remotely unsure about a plant, do not eat it. Sometimes there is a fine line between edible and inedible. For example, regular garden variety pea flowers and shoots are edible and delicious, while fragrant sweet peas (Lathyrus odoratus) are poisonous. Some varieties of daylilies are edible and others are not. The same is true for phlox and geraniums. Make sure you know what you have before tasting it.
Also, chemical sprays and car fume residue can be toxic, too. Chemical pesticides, herbicides, and insecticides should not be used on flowers that will be eaten. Never eat flowers from commercially grown plants, as there is no way to know for sure what has been applied to or used in growing these plants. Now that I have reminded you to be careful, let’s see just how many flowers in your garden are edible!
All herb flowers are edible.
Basil, chives, cilantro, garlic, dill, lavender, marjoram, mint, oregano, rosemary, sage, savory, and thyme flowers can all be used to add an extra depth and a touch of color to many different dishes. You can also eat the flowers of anise hyssop, angelica, bee balm, burnet, chervil, fennel, ginger, and lemon verbena.
There are a surprising number of edible flowers. All members of the viola family, which includes Johnny-jump-ups and pansies, and the dianthus family, or carnation fame, are edible.
Edible fruit tree flowers
The flowers of many fruit and nut trees are also edible. Apple, apricot, peach, pear, and plum blossoms can be used to add color and a delicate complexity to many dishes. When using these flowers, be sure to only use the petals, and not the stamens or pistils. Because they contain low levels of cyanide, apple blossoms should be eaten in moderation. Citrus blossoms are very pungent and should be used sparingly. Leftovers can be added to floral arrangements, so that you can still enjoy the aroma.
Edible vegetable flowers
Your probably already eat several vegetable flowers: artichoke, broccoli, and cauliflower, for example. While eating the flowers of your vegetable plants reduces your crop yield, it can be a nice way to try something new. There are several different vegetable plants with edible flowers:
Ways to use edible flowers
While it is easy to sprinkle petals into a salad for a splash of color and flavor, there are many other ways to incorporate edible flowers into your diet:
Preparing edible flowers
Edible flowers should be picked just before using and thoroughly rinsed off. This will help remove dust, frass, microorganisms, and any surface chemicals that may have blown in or been applied. Taste the flowers before using them, so that you know what flavor you are adding to your food.
Remove the pistils and stamens from most flowers. The only exceptions are violas and Johnny-jump-ups - in these cases, the other parts add good flavor. If you detect some bitterness in any edible flower, you may need to remove the white base of the petals. This is commonly needed when working with carnations, chrysanthemums, day lilies, and roses.
How many edible flowers do you have in your garden? Tell us in the comments!
The aroma of lilacs is intoxicating, and fleeting.
Here in San Jose, California., lilacs only bloom for a couple of weeks, near the end of May, but they are worth the wait. These cousins to olive trees and privet shrubs add beauty in a landscape, and the heady blooms are bound to attract pollinators.
The purple standard lilac (Syringa vulgaris) actually comes in 12 varieties. These small trees can range anywhere from 6 to over 32 feet in height! Most lilacs only bloom once a year, though some varieties have double-flowers. There are also some new reblooming, or remontant, varieties that flower multiple times within a single season. If you don’t have room for a full-sized lilac, you can try a dwarf. Dwarf varieties are becoming more popular in landscapes and as indoor plants, reaching heights of only 4 to 5 feet. Dwarf (or miniature) varieties of lilac are mostly variations on the Meyer lilac (S. meyeri), also known as a Korean lilac.
How to plant lilacs
Autumn is the perfect time to get your lilacs started. If you received an offshoot or root cutting from a friend, don’t worry if it is looking pretty pathetic right now. That’s normal. Simply select a good location and get started. Lilacs prefer well-drained, neutral soil (with a pH at or near 7.0) with lots of organic material. Most Bay Area soil is heavy, alkaline clay that doesn’t drain well. (Lilacs hate wet feet.) If you want to put lilacs in the ground, you will need to prepare the soil first. This means digging it up (but not when it’s wet) and incorporating aged compost or some other organic material (kitchen scraps, grass clippings, that sort of thing). If all that organic material is fresh, it will take time to break down. If you do not have the time to wait, simply dig the “waste burial holes” around where you want your lilacs. The earthworms and soil microbes will take care of it for you, and the lilac roots will find it. The hole should be as deep as the root ball and twice as wide. Multiple lilac bushes should be spaced 5 to 15 feet apart. Lilacs normally prefer full sun, at least 6 hours, but the scorching California summer heat really takes a toll on my lilacs. They end up needing a little protective shade from nearby trees and shrubs.
Growing lilacs in containers
To successfully grow lilacs in containers, you will need to select a dwarf variety and a large container. Lilacs prefer having room to spread their roots, so the container needs to be at least 12 inches deep and 24 inches wide. Be sure to use potting soil with a neutral pH. Lilacs dislike both alkaline and acidic soil. Water thoroughly at planting time and keep the soil evenly moist (not soggy) until the roots have taken hold. After that, water any time the top inch of soil dries out, and not before. Containerized lilacs need at least 6 hours of full sun every day to bloom properly. Many homes do not have that much direct sunlight, so you may need to supplement with grow lights. Stabilize temperatures and reduce moisture loss adding a thin layer of mulch, such as attractive redwood chips, around your potted lilac, just be sure to leave a little space between the mulch and shrub stems.
Caring for lilacs
Lilac flowers bloom on old wood, so pruning should be kept to a minimum. Pruning should be limited to removing dead, diseased, rubbing branches, suckers, and spent flowers. Since flowers are produced on older wood, do not put off deadheading your lilacs. If you wait until the end of the season, the wood that grows in will be too young to produce flowers the next season. If your lilac becomes unruly, cut all canes back to eye level and remove one-third of the oldest canes at ground level. The next year, cut half of the remaining old wood down to the ground. In year three, cut the remaining old wood. Or, you can cut the whole thing back to a height of 6 to 8 inches. This more drastic method creates the best blooms, in the long run, but it will take your lilac a few years to get back to full size.
Each spring, top dress the soil around lilacs with aged compost. Then, cover that top dressing with mulch. This will add nutrients and protect the microorganisms that help your lilacs get to those nutrients. Commercial fertilizer is not recommended for lilacs planted in the ground. Excessive nutrients causes plants to produce more leaves, and no flowers.
Lilac pests and diseases
I have found Fuller rose beetles to cause the most damage to my lilacs. Scalloped leaves are a sure sign of this pest. Lilacs are also susceptible to powdery mildew, phytophthora, and pseudomonas. Slugs and snails are said to cause some damage, but I have not had that experience.
If you already have a lilac, you can take root, shoot, and sucker cuttings to propagate new plants. Dig up some roots, or suckers with roots attached, and place them in a bucket with some water until you are ready to plant. You can also use 8 to 12 inches new growth twigs. Simply strip away most of the lower leaves and place them in rich potting soil and keep them moist (above and below ground) until roots start to grow. Since woody stems can be difficult to start rooting, many people apply rooting powder to the lower portion of the stem. Since rooting powders are synthetic plant hormones, I don’t use them.
While lilacs are not edible, I can practically taste their sweet fragrance. Also, the pollinators who are drawn to lilac blossoms often stick around to pollinate other plants in your garden.
Chamomile makes a soothing tea, an excellent ground cover, and, hey, it looks pretty. Just ask Beatrix Potter fans!
Seriously, these dainty little flowers have been used and enjoyed for a really long time. According to the National Institutes of Health, “Chamomile is one of the oldest, most widely used and well documented medicinal plants in the world and has been recommended for a variety of healing applications.” Scientific research has shown chamomile’s anti-inflammatory and soothing properties to be moderately to significantly effective against a number of digestive, respiratory, and sleep-related problems.
Attracting beneficials with chamomile
If all those medical conditions weren’t reason enough to add chamomile to your garden or foodscape, many beneficial insects are also attracted to chamomile. Syrphid or hoverflies, parasitic wasps, tachinid flies, bees, and other pollinators are attracted to chamomile.
There are many daisy-like plants that fall under the name chamomile, but only two genuine varieties: Roman and German. German chamomile (Matricaria recutita), also known as ‘Water of Youth’ or wild chamomile, is an annual that can grow up to 2 feet in height and 2 feet across. Roman, English, Russian, or garden chamomile (Anthemis nobilis) is a low-growing perennial, often used as a ground cover or lawn replacement. When selecting chamomile plants for tea, be sure to select German chamomile and not Roman.
How to grow chamomile
Chamomile (or camomile) prefers full sun to partial shade and moderate amounts of water. It can be grown in a container or directly in the ground. Chamomile is best planted in protected areas if temperatures are expected to rise above 100 degrees F. Chamomile generally does not require supplemental fertilizer. Chamomile is best grown from established plant cuttings or division, but it can be grown from seed. Chamomile seeds require light to germinate, so they should not be covered. Seeds take 1 or 2 weeks to germinate. Plants should be cut back 3 to 5 inches every so often to prevent excessive size and legginess. Trimming will also promote flower production. If growing for tea, flowers should be removed (deadheaded) on the first day they bloom for the best flavor.
Chamomile pests & diseases
Chamomile is a sturdy, drought tolerant plant, but it may become susceptible to powdery mildew, white rust, leaf blight, aphids, thrips, and mealybugs if weakened by lack of water or other environmental stresses. Several beetles find chamomile flowers to be as appealing as we do, so it is important to wash plants off when harvesting, to avoid contaminating your tea.
The bad news
Just when you had every reason to add chamomile to your garden, it is important to know that it is not for everyone. All the chemicals that make chamomile so helpful can also make it harmful. People who are sensitive to ragweed or chrysanthemums may develop allergic reactions to chamomile. Also, since chamomile has been shown to stimulate uterine contractions, it should be avoided by pregnant and nursing women.
You can dry chamomile flowers in an old pillowcase, the same way you can preserve lavender. Dried flowers should be stored in an airtight container out of sunlight.
So, put the kettle on and have yourself a piping hot cup of soothing chamomile tea.
Germander is a rugged, woody, fragrant variety of plant from the mint family.
If you are looking for a handsome, drought tolerant plant that can grow in pretty much any soil, consider germander. Full sun, partial sun, clay soil - germander doesn’t seem to care. And the deer leave it alone!
Germander actually refers to an entire genus of plants called Teucrium. These plants are from the Mediterranean and eastern Europe. They grow wild in poor, rocky soil, so our California clay and drought are no problem.
There are several varieties of germander to choose from:
Germanders of all types feature sturdy pale green to grayish-green to foliage. These evergreens can have tiny flowers, like rosemary, or flowers on spikes. The leaves of some varieties can be very aromatic when crushed or brushed against. The color, structure, and fragrance have made germaders a popular choice for formal knot gardens and parterres. Their low maintenance durability make them excellent border plants, ground covers, and landscape anchors.
Butterflies, bees, and other pollinators love germander flowers for their pollen and nectar. Germander can be grown in containers, indoors or out. Most germander varieties tend to get leggy, so pinching off or cutting stems just above leaf intersections can promote a bushier growth. Germander’s characteristics make it useful in many ways:
How to grow germander
As a member of the mint family, germander is easiest to grow from cuttings and division. You can simply pull a piece of existing plant from the ground and put it in some moist soil. New roots should be visible before long. You can also snip a stem and treat it the same way. If you grow germander from seed, it may take a month for them to germinate. I don’t know about you, but a seed that takes that long to break ground is often forgotten about - especially if I forgot to use a plant marker. Take a look at germander the next time you visit a garden supply store. They normally have several varieties available. Germander pests include mites, rust, powdery mildew, and leaf spot, but healthy plants are generally able to fend for themselves.
Do you have room for germander in your garden? I'd love to see photos!
Budworms - they're not just the bane of marijuana growers!
Budworms destroy flowers, buds, and leaves, and there are several types. All of them are the larval stage of certain moths. They are called budworms because they burrow into the flower buds of tobacco, marijuana, spruce, cotton, petunia, nicotiana, and geranium. After those resources have been exhausted, budworms start feeding on many other nearby flowers, such as roses, snapdragons, angelonia, and penstemon.
The budworm begins its life cycle as an egg. These spherical, flattened eggs are laid singly, usually on buds or leaves. The newly emerged larvae may be colored olive green to reddish brown, with longitudinal stripes and several rows of spines along the back. Depending upon the specific species of budworm and the food they are eating, the color may change to match the host food, making them difficult to see. Budworm larva go through several instars. After gorging on your flower buds and other plant parts for a month or so, adult caterpillars drop to the ground where they burrow down 4 to 6 inches and pupate into moths. There are generally two or three generations each year, in spring and summer. Each species has distinct descriptions and host foods. Two of the most common budworm pests:
Damage caused by budworms
Tiny budworm larvae burrow into small flower buds, where they feed and grow. As they become larger, budworm emerge from inside the ruined flower buds to feed on nearby mature flowers and leaves.
How to control budworms
Very often, budworm damage isn’t seen until flowers are open or the bud is destroyed. Monitoring buds regularly is critical for control. Check buds and flowers for small holes. Holes in buds will average 1/16 inch in diameter, while leaf and flower holes tend to be 1/8 inch. Handpick any visible caterpillars, which are normally most active during the evening and hide near the base of the plants during daylight hours. Chemical insecticides have not been found effective. Luckily, treatments containing Bacillus thuringiensis/Bt are effective when sprayed early and regularly enough. Rototilling or installing landscape cloth over affected areas during the fall may disrupt the budworm lifecycle.
Deadheading refers to the removal of flowers that are past their prime.
Since the production of flowers is part of a plant’s reproductive process, removing the flowers encourages the plant to produce more flowers, rather than entering the seed-producing reproductive stage.
How many of us, as children, pinched snapdragon blooms between our fingers to see the floral dragon open and close its mouth? Yep, count me in!
Standard snapdragons are classified as midget (6-8”), medium (15-30”), and tall (30-48”). There are also fairy snapdragons (pictured) that provide delicate, miniature versions of the blooms.
How to grow snapdragons
Snapdragons perform best in full or partial sun. They prefer well-drained soil and do well in rockeries. Unlike many other flowers, snapdragons can withstand frost and often provide cool season flowers.
Snapdragons are difficult to start from seed, but it can be done. The normal lifecycle of a snapdragon is to bloom in fall and winter (weather permitting) and then drop seeds in spring. These seeds are exposed to a lot of heat during the summer. If you want to grow snapdragons from seed, simply reproduce that cycle. Cold, damp weather or soil will halt their growth. After flowers have passed their peak, be sure to deadhead the plants for more blooms.
Snapdragon plants can become leggy and may need support. You can reduce this need by pruning the longest stems to form a bushier shape. Regular deadheading will promote more flower development.
Snapdragon pests & diseases
Once established, snapdragons should be allowed to dry out between waterings. They are prone to several fungal diseases, such as:
Anthracnose, root knot nematode, crown gall, and leaf and stem spot are also occasional problems on snapdragon.
WARNING: ALL PARTS OF SNAPDRAGON ARE POISONOUS IF EATEN.
Angiosperms are plants that produce flowers.
The word angiosperm comes from the Greek words for “vessel” (angeion) and “seed” (sperma). There are 350,000 known species of angiosperm plants and they all generate seeds. Nearly 80% of all the green living plants on earth are angiosperms. This is the most diverse group of plants in the world and they make up the majority of our food supply.
Plants with veins are called vascular plants. Vascular bundles, made up of the xylem and phloem, carry water and nutrients throughout the plant. Angiosperms are vascular plants. The way those veins are arranged within a stem can help you identify a plant. You know those long threads that get caught in your teeth when you eat celery? Those are plant veins.
Until recently, angiosperms were divided into two groups: monocots and dicots. Monocots, such as corn, have a single seed, a single embryonic leaf (cotyledon), fibrous root systems, parallel leaf veins, flower petals in multiples of 3, and scattered veins, whereas dicots, such as peas, beans, radishes, and nasturtiums, have seeds that split in half, two seed leaves, a taproot, webbed veining, flowers petals in multiples of 4 or 5, and a circular arrangement of veins.
Genetic testing and electron microscopes have taught us that those generalizations were too simplistic. As a result, dicots have largely been recategorized as a new group, called eudicots. If you want to get super technical, the modern plant classification system identifies 8 different angiosperm groups.
All angiosperms start out as seeds. Seeds are produced when the stigma of a female flower is pollinated by pollen from a male flower’s stamen and the ovules are fertilized. This process is called double fertilization. The seed is protected and fed by fruit that surrounds it. The fruit is actually a mature plant ovary.
Cereal crops, such as wheat and rice are also angiosperms, you just don’t usually see the flowers.
How many different angiosperms are growing in your yard?
A canker is a sunken wound in bark caused by fungal and bacterial diseases. The wound is an open sore filled with dead plant tissue. Okay, so it’s not the prettiest thing we’ve talked about, but it is important to know where cankers come from, how to prevent them, and how to treat them. Your trees will thank you!
Canker causes & identification
Some cankers are obvious and some are not. They are caused by fungal and bacterial microorganisms that infect the cambium layer of trees and shrubs. Cankers are very slow to heal and often do not heal at all. If the wound travels laterally, the sap found in the xylem and phloem cannot move and the branch dies.
Foliage on infected branches often turns yellow or brown and wilts. Cankers can encircle (girdle) and kill limbs or an entire tree. Common canker diseases include: Eutypa dieback, pitch canker, fire blight, Fusarium wilt, chestnut blight, pine blister rust, anthracnose diseases and sudden oak death.
How to prevent cankers
The best prevention method is planting resistant cultivars. Also, installing plants best suited to the local microclimate helps them to be strong enough to fight off pests and disease on their own. Good cultural care, such as proper pruning, watering and feeding will also help prevent disease. Whenever dead or diseased limbs are seen, they should be removed and destroyed right away. Avoid heavy feeding, since that stimulate vulnerable new growth. Sunburn and overwatering can both make plants susceptible to various canker diseases. Many healthy trees have these pathogens present. Trees that are stressed become susceptible to disease.
Once a fungal disease has taken hold, getting rid of it can be difficult. Most fungicide treatments are ineffective against fungal cankers since the pests are safely inside the plants they infect, and the same is true for bacterial cankers. Maintaining healthy plants allows them to fight for themselves.
These members of the Evening Primrose family (Onangracea) generally love filtered light and will even thrive in shady areas. They do not perform well in full sun. I hang mine in a basket from a branch in one of my orange trees. It looks pretty when it’s blooming and I don’t even notice it when it’s not.
Fuchsias prefer overhead watering and will need to be watered frequently during our hot summer months. Spider mite and fuchsia gall mite damage can be minimized with insecticidal soap. During flower production, feed a complete fertilizer every few weeks or use delayed release plant food stakes (my personal choice for containerized ornamentals).
In winter, I leave mine alone completely, and every spring it comes back adding a lovely touch of color. The hummingbirds seem to like it, too!
Spring is the time of year when it is common to see white powdery patches appear on leaves. This bane of gardeners is called powdery mildew, and it can occur in autumn, as well.
Cucumber, melon and other cucurbits are susceptible to powdery mildew. You may also see it on tomatoes, roses, snapdragons, chrysanthemums, peas, artichoke, beets, grapes and wheat.
What starts as a small white spot, powdery mildew expands to engulf an entire leaf as the nutrient-sucking fungi bleed the life from your garden. It can be found on either side of a leaf and sometimes on stems.
Powdery mildew identification
Powdery mildew is a fungal disease. It is caused by different types of fungi (e.g., Erysiphe spp., Sphaerotheca spp.), depending on which plant is affected. Contrary to common belief, moisture and humidity are not needed for these fungal beasties to appear.
The white powder seen on leaves is actually thin layers of fungal tissue (mycelium). Other symptoms of powdery mildew include:
How does powdery mildew grow?
Powdery mildew fungi simply need living plant tissue to survive and thrive. To make matters worse, their spores are carried on the wind, so the battle never ends. The reason powdery mildew seems to disappear in the heat of summer is that these microorganisms prefer shade and temperatures between 60° to 80°F. Our California summers are simply too hot for the spores to reproduce. Instead, they remain dormant until conditions improve.
Not only does powdery mildew cause leaf loss, it can also weaken a plant. This lowers production and increases susceptibility to other pests and diseases, such as citrus blast. Leaf drop can also lead to sunburn damage.
Powdery mildew management
Prevention and vigilance are the best ways to counteract powdery mildew. These tips can help, but nothing will eliminate powdery mildew in the garden:
Some people recommend spraying plants with a baking soda solution, but this can add too much salt to your soil.
More recent research shows that spraying the soil with milk before planting and then spraying the leaves of susceptible plants when the disease is most likely to start appearing can significantly reduce the incidence of powdery mildew in your garden.
Native to South and Central America, nasturtiums are rugged plants that provide lovely edible blooms.
The history of nasturtiums
When nasturtiums arrived in Spain in the 1500’s, they were called “Indian cresses” because of their peppery flavor and their use in salads. Nasturtium flowers have been gracing gardens since Roman times. Back when the Romans defeated an army, they would set up a trophy (tropaeum) pole on which they would hang the shields and helmets of the losers. Nasturtiums (Tropaeolum) earned their Latin name because, to Carl Linnaeus*, the rounded leaves reminded him of shields and the flowers looked like blood-stained helmets. (The word nasturtium literally means “nose tweaker”.)
The botany of nasturtiums
Nasturtium are perennial and annual dicotyledons, depending on the variety and local conditions. There are climbing and bushy nasturtiums. Nasturtium stems are somewhat succulent and the roots can be tuberous. One particularly rugged variety from Chile, T. polyplyllum, survives at altitudes of 10,000 feet! (Most of us would be out of breath and a bit wobbly at that elevation!)
Nasturtium flowers can be yellow, orange, reddish-brown, white, red, or even blue. Flowers have five clawed petals, with the bottom three looking different from the top two. Each bisexual flower has 8 whorled stamens. Nasturtium seeds look like naked nuts with three segments. Leaves may be rounded or deeply lobed. Leaf stems tend to be rather long. There are about 80 species of nasturtiums. Nasturtium are the only members of their genus.
How to grow nasturtiums
Until recently, it was believed that nasturtium seeds required scarification (damage to the seed hull) for germination to occur. We now know that this is not true. Seeds can be planted directly in the ground after the final frost date. Seeds should be planted 10-15” apart and 1” deep. Water regularly, unless a drought-tolerant variety is selected. Nasturtiums prefer well-drained or sandy soil. They perform best in full sun or partial shade. Once nasturtiums are established, you can easily end up with far more plants than you need. When this happens, simply transplant seedlings into a nice little container and gift them to family and friends!
Uses of nasturtiums
All parts of the nasturtium plant are edible, but most people only eat the flowers. The flowers look lovely in salads and add a nice peppery flavor to stir-fry. Nasturtium flowers contain the highest amount of lutein of any edible plant. Lutein is an antioxidant that protects the retina from free-radical damage by blue light, helping prevent macular degeneration. Unripe seed pods can be pickled in spiced vinegar and used like capers. The tuber of the Mashua variety (T. tuberous) is used in the Andes as a major food source.
In herbal medicine, nasturtiums are used for their expectorant and antiseptic qualities. They are believed to promote the formation of new blood cells and to relieve chest colds.
Nasturtiums attract butterflies and other pollinators. They can also be used in companion planting as target plants, to distract pests such as cabbageworms and mites away from more vulnerable plants. Nasturtiums are believed to repel Asparagus beetles, squash beetles, aphids, Mexican bean beetles, cabbageworms, and whiteflies.
Nasturtiums readily self-seed and they take little or no care once established. Add these lovelies to your garden or windowsill for some bright, flavorful blooms!
* Carl Linnaeus created our modern system of naming plants and animals in something called binomial nomenclature.
You pluck an orange from a tree and a tiny white insect flies out from under a leaf. On the underside of that leaf is a strange white spiral. You have discovered whiteflies.
Whiteflies are not related to flies at all. Instead, they are close cousins to aphids, mealybugs, soft scale and armored scale. These pests cause billions of dollars in plant damage each year, sucking the sap from 500 different plant species, including your cabbage, cucumbers, eggplant, melon, squash, and tomatoes.
Whiteflies got their name because most of them look like tiny white flies. Adult bodies are actually yellow or black, but they are hard to see. Whiteflies have 4 white wings and are often no bigger than 1 mm, which means you could stand 14 of them, end to end, across an American dime.
There are more than 1500 whitefly species, worldwide. In California, we have 10 whitefly species that cause problems in the garden:
Whiteflies are quick and difficult to see. It is easier to tell if a garden is infested with whiteflies if you see white spirals on the underside of leaves. These spirals are whitefly eggs.
Adult females walk a spiral path, laying eggs in a waxy trail that holds the eggs to the leaf. In warmer parts of California, whiteflies can breed year-round. Whiteflies can reproduce at mind-boggling rates. They go through four developmental stages, or instars. Eggs hatch out as nymphs, called crawlers. The next three stages are nearly immobile, much like scale insects. The final instar is a pupal stage.
At each stage, these pests use piercing mouthparts to suck sap from the phloem of a wide variety of garden edibles and ornamentals, causing leaf drop and a general failure to thrive. The honeydew (sugary poop) left behind is host to sooty mold. Honeydew also attracts ants, which then protect whiteflies from their natural enemies. Some whitefly larva may transmit viral diseases, such as cucurbit yellow stunting disorder and tomato yellow leaf curl. Also, adults can carry other pathogens. Low whitefly populations are not a significant problem, but they can make trees look shabby.
Heavy whitefly populations are very difficult to control. Any leaves with whitefly eggs should be removed and discarded. If the leaf looks particularly healthy, you can simply rub your thumb over the eggs to destroy them. Reflective mulches repel adult whiteflies, aphids, and leafhoppers. Also, yellow sticky traps can be used to trap and monitor whitefly populations.
Natural predators, such as minute pirate bugs, green lacewings, big-eyed bugs, and hummingbirds are the best defense against whitefly infestations. You can attract these garden helpers by planting zinnias, bee balm, hummingbird bush and pineapple sage.
Whitefly population explosions are often created when gardeners apply broad-spectrum pesticides that kill off beneficial predators, or when ants are allowed free access to host trees. Ants can be prevented from protecting whiteflies by applying a sticky barrier around the trunk. Dusty conditions can also put the odds in favor of whiteflies. Washing off dusty plants with a garden hose can help reduce whitefly populations.
According to companion planting lore, whiteflies can be discouraged from an area by planting basil, mint, thyme, and nasturtium. I don’t know if that works, but those plants are nice to have, in any case.
You may be surprised to learn, as I was, that plants release chemical compounds when bitten by insects or herbivores. These chemicals communicate with nearby plants, telling them to start protecting themselves against specific threats. These chemical messages also alert parasitic wasps and other beneficial insects, calling in the troops to protect the plant.
Researchers have recently learned that silverleaf whiteflies have developed the ability to flip this self-defense mechanism to their advantage. It works like this. Whiteflies are known to carry viruses. When a whitefly bites a plant, the plants used to defend themselves against the whiteflies. Now, they work harder to defend themselves against potential viral infection and create a more suitable whitefly habitat. This misinformation spreads to nearby plants, creating a cascade effect that can be very difficult to manage.
It’s a war zone out there!
Nectar is the sugary liquid found in flowers. While the ratios can vary, nectar is generally 55% sucrose, 21% fructose, and 24% glucose. Basically, it’s the fruit punch of the plant world. Nectar is produced in a gland. [Who knew plants had glands?!!?]
Nectar as food
Other plants use nectar as payment to mutualistic animals and insects that attack the plant’s enemies. The glands that produce nectar as a food for these beneficial insects and other animals is physically separate from the flower. They are called extrafloral nectaries. Bats, hummingbirds, butterflies, lady beetles, moths, wasps, ants, and bees all eat nectar. They also chase off, attack, and kill insect herbivores and seed easters that may threaten this easy food source. As these beneficials move from flower to flower, feeding on nectar, they can also carry pollen and improve pollination rates.
Nectar to honey
Honey bees collect nectar and use it to make honey. Nectar has a much higher water content (60-80%) than honey (20% or less). Honey bees “ripen” the nectar by mixing it with enzymes in their abdomen. Then they regurgitate it and fan it with their wings to evaporate the water.
Acrobatic hummingbirds are delightful garden visitors. Not only are they fun to watch, they are excellent pollinators!
Creating a habitat for hummingbirds increases pollination, reduces pests, and adds biodiversity to the landscape. Hummingbirds are naturally attracted to red, tubular flowers. Adding these plants to the garden is a beautiful attraction to hummingbirds.
Water features are another way to attract hummingbirds. Misters and sprinklers, rather than a birdbath, are the best bets.
Hummingbird feeders are a popular method of attracting hummingbirds, but the red dye contained in commercial food may not be good for these tiny fliers. There isn’t any real research available, but Red Dye #40, the most commonly used, is made from coal tar. It just doesn’t sound healthy. Plus, there is no need to add dye to the sugar-water mix in a hummingbird feeder. Most feature red plastic, which is all that’s needed to get a hummer’s attention.
To make hummingbird food, mix 1 part white sugar with 4 parts water and stir well. Do not use brown, ‘raw’ or turbaned sugars, as they contain iron, which can become toxic to hummingbirds. Honey and artificial sweeteners should also be avoided. To reduce the chance of bacterial and fungal infections, it is recommended that this mixture be boiled for 2 minutes and then cooled before putting in a feeder. (Extras can be stored in the refrigerator.)
Hummingbirds are very territorial and they will aggressively defend their food supply against other hummingbirds. To offset this tendency, planting a wide variety of flowers and hanging multiple feeders in different areas of the yard will attract the maximum number of hummingbirds to the garden.
A hummingbird’s long beak can reach nectar from flowers that many other pollinators dismiss, leaving the pollen untouched. Hummingbirds also eat nectar and insects, such as gnats, flies, ants, and spiders. So, the next time an ant trail is seen leading to the hummingbird feeder, leave it alone. These tiny morsels are like protein-infused potato chips to a hummingbird!
Unlike most other birds, hummingbirds seem to have a genuine curiosity about humans. If you are very patient, you can even get a wild hummingbird to perch on your finger!
Borage, or Starflower, is an easy-to-grow cucumber-flavored herb that thrives just about anywhere, even in areas affected by drought. Honey bees will flock to any garden with borage, improving pollination of nearby crops.
Native to the Middle East, borage was believed to ‘gladden the heart’ and to bring on bravery and courage - who doesn’t need more of that? The star-shaped flowers emerge pink or pale purple and then darken to bright blue. A white flowered cultivar is also available.
Borage (Borago officinalis) is an annual that grows very quickly from seed, reaching a full size of 2-3 feet in just a couple of months. Borage grows so fast that it can become top heavy and individual branches may fall to the side. But don’t worry - those spaces will quickly be filled with new stems and abundant bright blue flowers. Pinching back stems can prevent plants from becoming top heavy.
How to grow borage
Borage seeds can be sown directly in the ground after the last frost date. Seeds should be covered with 1/4-1/2” of soil and kept moist, but not soggy, until sprouts emerge. Overwatering is the biggest mistake gardeners can make when growing borage.
Borage prefers well-drained soil in a semi-neutral pH, with full or dappled sun, but it is often found thriving in the worst possible locations. Once borage plants are established, they need practically no care at all. Due to its tap root, borage is not suited to growing in containers. If that is your only option, use the largest container possible and pinch stems back frequently.
Select a dedicated site when growing borage because it reseeds readily, which means it will be around for a long time. Adding a thin layer of mulch each fall will feed and protect the next year’s generation. Temperatures permitting, borage plants will be a popular favorite of honey bees all summer long. Planting borage near cucumber, tomatoes, brassica, beans, grapes, summer squash, peas, and strawberries can significantly improve pollination and production.
Borage is an excellent addition to any butterfly garden and its calcium and potassium content benefit compost piles.
Culinary uses of borage
Every part of the borage plant, except the roots, is edible. The honey-flavored flowers can be added to salads for a splash of color or candied and used to decorate baked goods. You can even freeze borage flowers in ice cubes for a delightful summer soirée! Borage seeds are cultivated for their oil and the flowers are frequently included in potpourris. In Italy, borage is used to stuff ravioli. Frankfort, Germany boasts a delicious green sauce made from borage.
Some gardeners are put off by the tiny hairs found on borage, but those hairs give the plant a glistening appearance and they won’t hurt you. You may want to wear gloves, however. The cucumber flavor of young leaves can be included in salads and older leaves can be chopped up for soups or sautés. They can also be brewed for a refreshing tea.
Do yourself and your local honey bee population a favor and start growing borage today!
Lavender has been used to sooth upset stomach, irritated skin, and bad hair days for over 2,500 years.
Like other plants in the mint family, the essential oils found in lavender have sedative, antiseptic, antimicrobial and anti-inflammatory properties. The word ‘lavender’ comes from the Latin verb which means ‘to wash’ or ‘to bathe’.
Lavender flowers are used in sachets, soaps, linen spritz, soup, and frosting. These edible flowers can be candied and used to decorate baked goods, or added to teas, chocolates, and cheeses. Some people swear by lavender as an insect repellent, rubbing the leaves on skin or clothing. I don’t know if it works but I imagine it smells better than bug spray.
That being said, the U.S. National Institutes of Health (NIH) does not recommend lavender for women who are pregnant or breast-feeding, or to pre-adolescent boys, due to potential hormonal problems. For some people, lavender can cause skin irritation. And some people just don’t like it. For those who do, this easy to grow perennial can add color to your landscape. Lavender also provides pollen and nectar for many beneficial insects, especially honey bees.
How lavender grows
Being from a rocky Mediterranean region, lavender prefers hot, dry weather and loose, coarse soil. The root system tends to be significantly larger than the above-ground portion of the plant. These plants can live for 50 years and, being a mint, they will spread using underground runners, or rhizomes.
There are over 35 species of lavender, with more than 250 named varieties. Generally, they are categorized as either ‘hardy’ or ‘tender’. Hardy English (or Dutch) lavenders (Lavandula angustifolia or L. intermedia) are the most commonly grown. These varieties are hardy to Zone 5. Tender lavenders include Spike, Wooly, Egyptian, Spanish, and my all-time favorite, French lavender. Tender lavenders generally cannot handle frost. If an especially cold period is expected, tender lavenders can be protected with a cloth cover or an umbrella. Hardy varieties are better suited to Zones 1-4. When shopping for lavender, be sure to look at the label for the botanical name, so you know what you are getting.
How to grow lavender
Lavender can be grown from cuttings, layering or root division. Before installing a new lavender plant, however, you need to select a good site. Lavender does best where there is plenty of air flow, loose soil, and sunlight. Also, these plants will spread, so you may want to put them in large containers. Container planting is particularly useful in areas with cold winters, as you can move plants into protected areas for the winter.
Because air is so important to lavender, be sure to work the soil so that it is loose enough to dig into it with your hands before planting. Also, keep mature size in mind. Some varieties can reach 5’ across. Lavender prefers slightly alkaline soil, with a pH between 6.7 and 7.3.
Lavender uses a lot of phosphorus, so bone meal is a good soil amendment if your soil test indicates a lack. [This is highly unlikely west of the Rocky Mountains.] Mindful weeding during the first 2 years of a lavender’s life will go a long way toward ensuring a healthy, long-lived plant.
Lavender pests and diseases
Lavender grown in compacted soil with poor drainage will commonly end up with root rot, black mold, and other fungal diseases. Top dressing around lavender plants with aged compost or wood chips can improve drainage over time. You can also mulch around lavender with light-colored stones or oyster shells, which will reflect more light up into the plant. This will help reduce the chance of fungal disease. [If your soil already contains plenty of calcium, the stones are a better choice.]
You may occasionally see frothy areas on your lavender plants. These are caused by spittlebugs. If spittlebug infestations become troublesome, simply spray them off with a hose. They are not usually a significant problem.
Lavender winter care and pruning
Many people think their lavender has died over the winter, but this is rarely the case. In early autumn, simply cut back the green portion of the plant until only a couple of inches of green remain. This will help your lavender look nicer during the winter and it will stimulate lush growth in spring.
Some lavender plants fall open in the middle, in a behavior known as ‘sprawling’. This happens when the weight of new growth is more than the plant can support. In the wild, this is a great behavior because it allows new shoots resting on the ground to generate new plants. In your landscape, however, it won’t look as nice. You can prevent sprawling by pruning back 1/3 of the plant in spring, then pruning back 1/3 of the new growth that follows. This will create a nice shape and it will help the plant remain upright and full.
Lavender should be harvested when the florets first open. Snip off flowers just above a leaf pair to encourage new growth. Long-stemmed hardy varieties can be bundled and hung upside-down in a dark place to dry. Shorter-stemmed tender varieties, which tend to lose their flowers as they dry, can be threaded and hung in a pillowcase, so none of the flowers are lost.
I use my guest room closet for drying lavender. It stays dark and I like to think the aroma is soothing to overnight guests.
Lavender is a lovely addition to stumperies, rock gardens, and sensory gardens.
Honey bees are pollination workhorses.
It is estimated that honey bees are responsible for pollinating one-third of all U.S. agricultural crops, including herbs, melons, cucumbers, almonds, berries, butternut and other squash, apples, pears, and peaches. Honey bees are not native to North America, so there are no native plants that require pollination by honey bees. Just the same, most gardeners are very happy to see honey bees in the garden.
All bees are considered beneficial insects. Sterile female worker bees are either pollen, nectar, or water collectors. Water collectors are very important to hive health. Water is used to regulate temperature and in the creation of food. In winter, the water is used to dilute crystalized honey. If a water collector returns to the hive and is immediately relieved of her water, she will know that the hive needs more. If she must wait a while before an in-hive worker takes the water, she will know that demand is not critical and fewer bees will search for water.
As nectar collectors travel from flower to flower, drinking as much nectar as they can, pollen grains stick to their legs in cup-shaped containers. As pollen is knocked off these worker bees, a wide variety of crops and flowers can be pollinated. The workers then return to the hive, loaded down with nectar and pollen, which are handed off to other bees within the hive. The water in the nectar is allowed to evaporate and voila! Honey is made!
Honey bee taxonomy
Honey bees are distinguished from their non-stinging cousins by honey production and the creation of ongoing communal nests made from wax. Honey bees are members of the Apis genus. Their Asian and European ancestors have been around for 34 million years. The most commonly managed honey bee species is Apis mellifera and it was the third insect to have its genome mapped! Of the 20,000 known species of bees, there are 7 species of honey bee, with 44 subspecies. The study of honey bees is called melittology.
Honey bee identification
Most people are familiar with the fuzzy brown and gold striping of the honey bee and a few of us have experienced the painful sting of a honey bee on the defensive! Unlike wasps and bumblebees, honey bees die after stinging. People who work with honey bees, apiarists, use smoke to calm and subdue honey bees. They also wear white, which decreases the likelihood of being stung. [To a honey bee, we look an awful lot like dreaded bears. Wearing brown around a bee hive is just asking for trouble.] There are also black and brown bees - Russian, carnelian and others, but we don’t notice them as readily.
Honey bee lifecycle
Honey bees hatch from eggs laid by a queen in wax honeycomb cells. Before emerging as an adult honey bee, larvae are initially fed royal jelly (a liquid produced in the hypopharyngeal and mandibular glands of worker bees), and then bee bread, a paste of pollen and honey, as they go through several moltings. Then, they spin a cocoon and enter a pupal stage within the cell. Larvae intended to become queens are only fed royal jelly.
The queen is fertilized by multiple male drones from other colonies. The drones die after mating. Drones are produced by unfertilized eggs, while queens and worker females are from fertilized eggs. Each hive has a single queen, a few thousand drones, and tens of thousands of sterile female worker bees, depending upon environmental conditions.
During hot summer months, honey bees cool the hive with their wings and with a practice called bearding, in which bees hang on to each other and flap in the proverbial breeze until things have cooled off enough. During winter months, they huddle together in a winter cluster around the queen, to protect her from the cold. Honey bees consume honey stored in the hive during the winter
Honey bee communication
Honey bees communicate the location of food sources through a complex figure-8 dance called the waggle dance. They also instruct receiver bees to collect nectar from returning foragers with a tremble dance. Speaking of bee communication, it is traditional to talk to your bees, especially if you are going to be gone for a time, or if the beekeeper has passed away. Apparently, a hive will falter or fail if they aren't notified.
Honey bee pests and diseases
Honey bees have not evolved with an effective immune system. Their primary food, pollen, contains antibacterial components (if you are a bee). Varroa, tracheal and tropilaelaps mites, foulbrood bacterial infections, chalkbrood fungal infections, Nosema disease, and sacbrood virus are common honey bee diseases. If that weren’t enough, beetles, ants, wasps and hornets, wax moths and dragonflies attack bees or their hives.
Honey bees are also facing colony collapse disorder (CCD). This condition has many causes and was held responsible in 2008 for the death of 60% of the world’s honey bee population. It is considered normal to lose 10% of a honey bee colony during the winter months. Losses attributed to colony collapse disorder are reported as percentages of bees lost during a 12-month period, April through March. The figures I was able to find include 2014 (39%), 2015 (42.1%), 2016 (44%), 2018 (30%), and 2019 (37.7%). Unfortunately, accurate figures are difficult to find, but you get the idea.
How to attract honey bees
There are many plants that can be added to a landscape that will help you garner the benefits of improved pollination rates without raising bees. Of course, a small hive is simple to manage and fresh honey is amazing! Minimize the use of chemical pesticides and add these flowers to your landscape to bring honey bees into the garden:
In spring, it is not uncommon to see a swarm of honey bees. These bees are not dangerous. In fact, just before swarming, honey bees gorge themselves on honey so they are about as relaxed as they ever get to be. Unless, of course, you start flailing or threaten their queen. The swarm seen in the video was collected by beekeeper friends of mine only to discover that the bees had been sprayed with insecticides. All the bees died and my friends' equipment all had to be cleaned.
If a swarm starts collecting on your property, contact your local bee guild or County Extension Office for safe removal or start raising honey bees for yourself. Under no circumstances should you spray these garden helpers with pesticides or insecticides. Please educate your neighbors.
Colony Collapse Disorder (CCD) refers to the recent general die-off of honey bees worldwide. The causes of CCD may surprise you.
Healthy beehives may contain 10,000 to 60,000 bees, depending on the season and environmental factors. Traditionally, beekeepers expect to lose 20-25% of their bees each year. Bees are, after all, short-lived insects, that generally survive for only 4 or 5 months. Colony collapse disorder has doubled those losses.
Mysterious bee deaths
Colony collapse disorder is characterized by the mysterious disappearance of entire colonies of honey bees from their hives. Where there are normally visibly dead bees around a hive, bees affected by CCD have simply disappeared.
Unlike the rabble rousers who point to specific chemicals (neonicotinoids), corporations (Monsanto) or technologies (cell phone towers), researchers have discovered that CCD is the result of many factors.
The truth about bee losses
According to Dr. May Berenbaum, scientific spokesperson on Colony Collapse Disorder and head of the University of Illinois Entomology Department, explains that there are several factors leading to colony collapse:
• Honey bees are not native to North America. They were brought here from Europe a few centuries ago
• As the practice of beekeeping expanded, common bee pathogens and pests, specifically foulbrood and the varroa mite, led to the use of antibiotics, fungicides and miticides that can negatively impact honey bees while losing their efficacy against pests and disease
• Honey bees naturally lack many of the immunity and detoxification genes that the rest of us have
Honey bees do have the advantage of eating foods that boost the power of the protective genes they do have. Pollen increases the production of proteins that defend against pathogens and metabolizes toxic compounds. Don’t assume that those benefits extend to other species, such as us, because there is no scientific proof to back up all those popular claims.
Because there are several causes of colony collapse disorder, there is no single solution.
So what can you do to help honey bees? Plant flowers that honey bees like, avoid using broad spectrum pesticides, use chemicals according to their directions, buy locally produced honey, start beekeeping in your own yard, and stay informed.
You can grow a surprising amount of food in your own yard. Ask me how!
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