Robber flies assassinate their prey in the air, injecting them with paralyzing neurotoxins and enzymes that liquify their preys’ insides. Also known as assassin flies, robber flies (Asilidae) aggressively hunt other insects. They often look more like bees or dragonflies to the casual observer. And they are in your garden, for better or worse.
Robber fly description
There are over 7,500 different species of robber fly, ranging in size from 0.2 inches up to 2 inches long. All of them are sturdy, bristled flies with a distinct mustache, made of of bristles (setae), called a mystax. Robber flies, like many other insects, have three simple eyes (ocelli), in a depression on top of their head, between two very large compound eyes. [Simple eyes, like ours, have only one lens, while compound eyes have many lenses.] Robber flies generally have robust legs with spines, and short, segmented antennae. Most species of robber fly have long, skinny bodies with stinger-like ovipositors, while others look more like bumblebees. Robber flies will inflict a painful bite with their proboscis (tubular mouth part), if they feel threatened.
Robber fly life cycle
There is surprisingly little known about the private lives of robber flies. They seem to prefer dry, sunny, open environments. Each robber fly can live for up to 3 years. Eggs can be translucent (hyaline) or pigmented, spherical or oval, depending on the species. Yellowish or white larvae, with tapered bodies and a dark head, are believed to live in leaf mold, rotting wood, and in the soil. There are four larval stages, or instars. Scientists are only now learning about the feeding behavior of robber fly larvae. It’s pretty strange. For one thing, the first instar does not eat insects; it probably eats dead things. The second instar eats beetle larva secretions. [Don't ask.] Later instars are actual predators. Robber fly pupa are naked and have leg stubs, so they can move around, similar to hornworm larvae.
Robber fly prey
Robber flies are generalists. That means they will chase after and kill pretty much anything that flies by, beneficial or not. That is why I said, for better or worse.” Robber flies will kill many garden pests, but they will also kill beneficial insects. Some of these prey insects are pretty substantial in size, compared to a robber fly. But, adult robber flies are excellent fliers. You can usually hear them coming, but for their prey, it’s already too late. Hiding in ambush, a robber fly spots its target, gives chase, and grabs ahold with its tarsi (front legs) before injecting a chemical cocktail that paralyzes the prey and liquifies its insides. The most common victims of robber fly attack include:
They have also been recorded feeding on:
And, hummingbirds. It’s rare, but it has happened. You can see some excellent video of robber fly behavior at Mike Blair Outdoors.
Have you seen any robber flies in your garden? Do you consider them to be Good Guys or Bad Guys?
Hoverflies, or syrphid flies, are one of the most beneficial insects you can attract to your garden.
Hoverflies are members of the Syrphidae family. There are over 6,000 species worldwide and 300 on the West Coast. Many of them mimic bees and wasps to discourage predators, but they are harmless to humans. Hoverflies mimic bees and wasps in other ways, too, as both predators and pollinators.
With so much variety, there is no one description that covers all hoverflies (also spelled hover flies). They can be as large as 3/4” long or so small that you won’t notice them. They can be black or colorful, spotted, striped, or plain. What they all have in common is the fact that they tend to hover over their favorite flowers. There are some bee flies that also hover, but they are equally beneficial as both pollinators and predators, so you don’t really need to know the difference* between the two species. Hoverfly larvae are blind and deaf. They are only 1/32 to 1/2 of an inch in length. They may be green, brown, yellow, or nearly transparent. They may have a white longitudinal stripe.
* If you really need to know the difference, hoverflies have shorter legs, a prominent beak, and a line along the back of their wings, while bee flies have longer legs, a sloping face, and clear wings. Also, bee flies are more likely to be hairy. There. Now you know.
Once a female has mated, she will seek out a good place to lay her white, elliptical eggs. A good place, to a hoverfly, is one that looks like there will be plenty of aphids for her young to eat. After they hatch, hoverfly larvae hang onto a leaf with their back end and swing back and forth, looking for prey. Once found, the prey are poked and sucked dry. The larvae leave a trail of empty husks to show where they have been feeding. Eventually, the larvae create a green or dark brown pupa around themselves, where they will metamorphosis into adults.
Not all hoverflies behave in the same way, but there is enough variety to safely assume these are bugs you want in your landscape and garden. Some hoverfly larvae are saprotrophs, which means they each decaying plant and animal matter in the soil. This improves soil structure and makes nutrients available to plants. Other hoverfly maggots are powerful predators, devouring a lion’s share of aphids and other plant-sucking pests.
Hoverflies as predators
Most hoverfly species larvae will eat aphids, thrips, mealybugs, mites, scale insects, and leafhoppers. That’s a good thing, because these pests spread several diseases, including curly top, powdery mildew, black spot, rust, and sooty mold, just to name a few! Other hoverfly larvae prey on caterpillars, slugs, and codling moth larvae. In my book, there are no bad hoverflies.
Hoverflies as pollinators
As adult hoverflies feed on nectar and pollen, they also pollinate many of your garden crops. In fact, hoverflies are second only to bees when it comes to pollination. Unlike bees, which tend to prefer specific species, hoverflies are generalists, landing wherever the picking looks good.
There are several insectary plants that attract hoverflies. Most of these plants provide pollen and nectar to the adult forms. Hoverflies prefer plants that have shallow or umbrella-shaped flowers. These plants are often members of the Umbelliferae or Apiceae family. Adding the following plants to your landscape is sure to attract these beneficial insects:
Research has shown that hoverflies prefer yellow and white flowers over other colors. Since organic pesticides, such as spinosad, also kill beneficial hoverflies, you may want to think twice about when you spray. Once flowers are in bloom, you may want to hold off.
Orchid trivia - One type of orchid, Epipactis veratrifolia, emits chemicals that mimic the alarm pheromones used by aphids. This attracts hoverflies, resulting in pollination. Stuff like that makes me wonder what else is going on that we never notice...
Salvia is tough and beautiful. The bees love it and you probably do, too!
This member of the mint family is one of those no-brainer plants here in the Bay Area. Composing the largest genus of mints, this group of plants includes the culinary favorite, sage (Salvia officinalis). Most ornamental salvias are referred to by their Latin name. The word salvia comes from the Latin word ‘salvere’, which means to feel well and healthy.
Salvias tend to be woody plants, which is one reason why they are so good at handling drought. Depending on the variety, they can be evergreen or deciduous, annual, perennial, or biennial. Like other mints, the stems tend to grow at angles to each other and are square. The flower spikes are the big attraction. They consist of a modified leaf, called a bract, and stalked, clustered flowers, called racemes or panicles. Flowers can be red, pink, yellow, or white, but the deep blueish-purple is my favorite. Hummingbirds, butterflies, and other beneficial pollinators love them, as well.
Weird salvia science
Unlike most mints, which have four stamens, salvia have a unique pollination mechanism that uses only two stamens and connective tissue (thecae) that create a lever action. Within male flowers, this lever action causes pollen to be dumped on any visiting pollinator. After the pollinator leaves, everything returns to its normal position. In female flowers, the same mechanism pushes the stigma to be in the same general area on the pollinator’s body, increasing the likelihood of pollination and fertilization (assuming they are the same size).
How to grow salvia
Salvias can be grown from seeds, seedlings, or cuttings, depending on the variety, once the last frost date has passed. Most salvias prefer full sun and good air circulation. An exception is the Japanese yellow sage (Salvia koyamae), which prefers shade and moist soil. If your soil is heavy clay, like mine, you will want to incorporate some aged compost to lighten it up before planting. Salvias will produce more blooms with regular feeding. You can also mulch around plants with aged compost for reduced moisture loss and slow-release feeding. If you prune your salvias before they bloom, flowering can be significantly delayed. Better to shear your salvias at a time of year when they are not flowering. And be sure to deadhead spent blooms the rest of the year to stimulate more flower production. While being drought tolerant, your salvias will need to be watered. Just wait until you notice some moderate wilting, to avoid common fungal diseases.
Salvia pests and diseases
Rust, powdery mildew, and leaf spot may occur, but they can often be prevented with proper water management [Read: avoid overhead watering]. Aphids and thrips will be the most common pests. [Aren’t they always?] Many salvias have hairs on leaves and stems that discourage many pests and grazers (and my chickens).
Whether you choose edible culinary sage, fragrant pineapple sage (Salvia elegans), the sacred white sage (Salvia apiana), or sturdy purple sage (Salvia dorrii), try adding some salvia to your landscape or garden today!
Bee balm is a striking North American native that attracts more than just bees to your garden.
Bees and other pollinators are what help your garden plants produce the fruits and vegetables we love. Adding plants that they love can increase your bounty many times over. Bee balm also provides pollen and nectar to other beneficial insects.
Antiseptic bee balm
Bee balm is a perennial. It is also a member of the mint family. Like other mints, bee balm has antiseptic properties. In fact, it is still used as a primary ingredient in popular mouthwashes. Native Americans used bee balm leaves and flowers to treat headaches, wounds, flatulence, and respiratory problems. They also used it to season wild game. While somewhat bitter, it tastes like a combination of peppermint and oregano.
The bee balm plant
Bee balm (Monarda), also known as wild bergamot, horsemint, and Oswego tea, loves sunshine. If it is grown in partial shade, it will stay low to the ground and produce very few flowers. Grown in full sun, it can reach four feet in height, though most are only half that. The flowers, which tend to appear in early to late summer, are striking, with white, pink, and purple tubular daisy-like blooms. You can also find dwarf varieties that look lovely in containers.
How to grow bee balm
Bee balm, like other mints, prefers rich, moist soil. If enough moisture is present, bee balm can overtake an area. Some varieties can tolerate more dryness than others, so do your homework. It is easiest to buy bee balm plants from a reputable seller, or, if you know someone with an established plant, you can ask them to share some with you the next time they are dividing their plants. Bee balm can be planted in spring or fall. Plants should be spaced two feet apart, and the planting hole should have some compost worked into it, to a depth of 12 to 15 inches.
In most regions, bee balm prefers full sun, but scorching California summers can sometimes be a bit much, so you may want to place your bee balm in where it will be protected from direct sunlight in the hottest part of the day. On the flip side of the calendar, your bee balm plant may die back to ground level in the winter, but don’t panic. Simply cover the area with mulch and it will be back when temperatures warm.
Bee balm pests and diseases
Powdery mildew is really the only problem that occurs with bee balm. You can protect your bee balm from powdery mildew by avoiding overhead watering and by pruning for good air flow. Fungicides can be used with marginal success.
Caring for bee balm
Bee balm is a low maintenance plant. You will want to provide it with a layer of compost each spring, covered with mulch, for good soil health. It may need to be watered during the peak of summer and be sure to remove spent blooms (deadhead) to encourage fresh flowers throughout the growing season.
So, sooth your senses and savor the site of butterflies and bees in your garden with bee balm!
Flies with mohawks are out to save your garden!
A tachinid fly looks like a small, sturdy house fly with a mohawk on its rear end. These tiny flies use many common garden pests to feed their young. Let’s find out how.
Tachinids as parasitoids
Tachinid flies are second only to parasitic wasps in pest control. Different tachinid species make use of different hosts in a number of ways. Most are parasitoids, which means they end up killing their host, while some are parasitic, which means the host may live. Tachinid flies parasitoid host insects to provide a guaranteed food source for their offspring. To parasitoid a garden pest, tachinid flies use several different methods. They may lay eggs on leaves favored by preferred caterpillars. When the larvae hatch, they are consumed by the caterpillar along with the leaf. Once inside the host, the larvae (maggots) begin their own feeding. Other tachinid species glue their eggs to the body of a host. When the eggs hatch, the maggots start feeding. Yet others using a piercing ovipositor (egg depositor organ) to inject the host with the eggs. Maggots feed until they are ready to pupate. Then, they drop to the ground and a hard casing forms to protect them as they morph into an adult fly.
You can attract tachinid flies to your garden or landscape by providing pollen and nectar for the adults from flat-topped (carrot, dill, yarrow) and composite (rudbeckia and aster) flowers. These beneficial insects also feed on aphid honeydew.
So, before you grab the fly swatter, take a closer look to see if that picnic pest is sporting a mohawk on its rear end.
Big-eyed bugs are your friend.
There are several different members of the Geocoris, or big-eyed bug family, and all of them are predators. This means they love to eat the pests that suck the life out of your garden plants, spreading disease as they go. The more big-eyed bugs you have in your landscape, the better.
Big-eyed bug diet
Gardeners should appreciate big-eyed bugs. These predators feast on small caterpillars, flea beetles, mites, cabbage loopers, whiteflies, and many different insect eggs. Research has shown that a single big-eyed bug nymph may consume up to 1,600 spider mites in its lifetime!
Attracting big-eyed bugs
You cannot currently purchase big-eyed bugs, but you can certainly lure them in with plants that provide nectar for when prey is scarce. While many beneficial insects prefer the flowers of carrot, fennel, and onion, big-eyed bugs prefer yarrow above all else. Yarrow is a sturdy, attractive border plant and it takes very little care to stay attractive.
Plant some yarrow today for your local big-eyed bugs!
Summer iced teas, winter colds, and many fruit and fish dishes are all made better with lemon balm.
This easy to grow perennial herb is a member of the mint family, which means it is a rugged, tenacious, and fragrant addition to your foodscape.
Using lemon balm
Also known as cure-all, sweet balm, and honey plant, lemon balm adds a soothing lemon flavor to teas, tinctures, and steam. Traditionally, lemon balm has been used to treat digestive upset, anxiety, thyroid disease, Alzheimer’s disease, ADHD, high blood pressure, sores, and even insect bites. Scientific research has demonstrated that lemon balm does provide some significant benefits (besides making a great cup of tea):
Unlike other herbs, lemon balm loses much of its flavor when dried, so fresh is better. I just learned that there is a lemon balm pesto recipe - I’ll let you know how it tastes in an update.
How to grow lemon balm
Once lemon balm is established, it will readily self-seed, so choose a site that has room for it. Individual plants can reach 2 feet in height and width. It can also spread vegetatively, where twig ends touch the ground and develop roots. Unlike many other members of the mint family, lemon balm does not spread using stolons (runners). Regular trimming will keep lemon balm plants healthy and attractive. You can also grow lemon balm in a container. My in-ground lemon balm has always stayed rather low-growing and has been pretty year-round (even after frost!) with just a little bit of trimming. Lemon balm normally dies back in winter above-ground, but comes back in spring. Lemon balm seeds require light and warmth (70 °F) to germinate, but the mature plants prefer some afternoon shade. Lemon balm prefers rich, moist soil with good drainage, and a pH of 6 to 7.
Lemon balm attracts honey bees!
The scientific name of lemon balm, Melissa officinalis, is a reflection of how much it attracts honey bees. The word ‘Melissa’ is Greek for bee. Small flowers, which can be white, pink, red, or yellow, appear each summer, packed with nectar. Many beekeepers throughout history have planted lemon balm near their hives. Whether you keep honey bees or not, attracting them to your garden is sure to improve pollination and production.
Add lemon balm to your garden, landscape, or balcony for healthier bees and a happier you!
We’ve all heard some seeds or plants described as heirlooms and others hybrids, but what do those terms really mean?
Both hybrids and heirlooms come about through naturally occurring cross-pollination, as opposed to genetically modified organisms (GMOs), which are created in a lab using altered DNA strands. Personally, I think we are setting ourselves up for a Major Fail, messing with DNA that way. I do not use GMO seeds or plants in my garden or landscape.
[Did you know that some governments (the USA included) have passed laws making it illegal to save or share certain seeds harvested from plants grown at home? This is because some GMO and hybrid seeds have been patented by corporations.]
Before agriculture became an industry, people grow a wider variety of plants for food. That biodiversity helped offset inclement weather, diseases and pests, and other threats to a failed crop and the resulting starvation. Corporate agriculture, on the other hand, feeds countless millions by generating a smaller variety of uniform plants that consistently grow at specific rates, that can be sprayed with a variety of pesticides, herbicides, and fungicides, ship well, and store well. As many of you know, taste and texture often suffer s a result.
Pros & cons of heirlooms
Heirloom seeds are those that have been handed down, person to person, in a specific geographical region, for a very long time. Also, heirlooms are open-pollinated, which means pollination occurs naturally, by wind, birds, animals, and insects, and not by human efforts. Heirloom varieties are at least 50 years old (some say 100 years), and many of them have been grown consistently, in the same locale, since before WWII. These plants have evolved to take advantage of local microclimates and beneficial insects. Heirloom seeds are hand selected by gardeners from the very best plants each growing season. Many heirloom plants do not have the uniformity or long term storage capabilities of hybrids, but growers (myself included) claim that the flavor is significantly better. Heirloom crops have more variety in size and shape than hybrids, but they always grow true to their parent plants. Heirlooms are more genetically diverse, making them more durable as a species, and less susceptible to local pests and diseases. Heirloom offspring are fertile and can reproduce.
Pros & cons of hybrids
Hybrid plants are intentionally created by cross-pollinating different varieties of a species. The intention of hybridization is to take advantage of the best characteristics of each parent plant, creating what is known as hybrid vigor (heterosis). This vigor only lasts for one generation. Hybrid seeds do not grow true to their parents and they lack vigor and genetic diversity. This lack of diversity is what caused the Irish Potato Famine of the 1840s. If all the plants are identical, they are equally susceptible to pests and diseases. A single threat can be devastating.
Creating a hybrid that grows “true” to the desired characteristics takes years of diligent effort. Plants are often pollinated by hand or grown in greenhouses or pollination bags that block contamination from outside pollen to ensure that pollination only occurs between the desired plants. The majority of the fruits and vegetables you see in grocery stores are hybrids. Harvests are very consistent in size and shape. Hybridization is done for many specific characteristics:
When shopping for plants and seeds, one way to know if it is a hybrid is to look at the Latin name. If you see the letter “x” between words in the name, it is a hybrid. For example:
Raspberry (Rubus idaeus) crossed with blackberry (Rubus ursinus)
creates Loganberry (Rubus x loganobaccus)
*Check labels for the letters V, F, N, T or A. These symbols indicate a resistant to verticillium wilt, fusarium wilt, nematodes, tobacco mosaic virus or alternaria stem canker, respectively.
Understanding the difference between heirlooms and hybrids can help you make the right choice if you want to collect viable seeds from your harvest for next year’s planting.
Soldier beetles rank right up there with lady beetles and lacewings in the world of beneficial insects.
Soldier beetles are predators that love to eat aphids. For that, alone, they are loved by gardeners. They also help pollinate crops as they feed on pollen and nectar. Soldier beetle larvae love to eat the eggs and larvae of moths and butterflies, beetles, armyworms, and other insect pests.
Soldier beetle identification
Unlike many hard-shelled beetles, soldier beetles have softer, more leathery bodies. In fact, some people call them leatherwings. There are many different species of soldier beetles (Cantharidae), but they all have rather long, narrow, rectangular bodies that are approximately 1/2 inch long. They commonly have a red, orange, or yellow head, back and abdomen, with dark grey or brown wing covers. You will see a large dark spot on the wings, when open. The larva are long, flat, and dark colored. Larva are often found under bark and in leaf litter.
California is home to more than 100 different species of soldier beetle. There is another bug with an almost identical name, spined soldier bug (Good Guy), but they look more like brown marmorated stinkbugs (Bad Guys). If you look closely in the garden, you will see these soldier beetle lookalikes:
Encourage soldier beetles in your garden by:
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 (NIH), “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.” In fact, it would almost be easier to list the conditions for which chamomile doesn’t help. Scientific research has shown chamomile’s anti-inflammatory and soothing properties to be moderately to significantly effective against:
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 mealy bugs if is 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.
Spiders in the garden may provide a frightful shock for those on the phobic end of the arachnid spectrum. For the rest of us, seeing spiders indicates a healthy ecosystem with plenty of biodiversity. How do spiders help your garden and which ones should you be worried about?
What makes a spider a spider?
Spiders are not insects, even though they have exoskeletons, jointed bodies and appendages, and they breath air. Spiders and insects are both arthropods. The difference is that spiders have six or eight eyes, eight legs, and fangs that inject venom, which insects do not. Also, spiders do not have antenna. Spiders and scorpions are both members of the arachnid class. Spiders have a more centralized nervous systems than other arthropods, and they move their limbs using hydraulic pressure, rather than muscles. The webs we see are produced from glands that make silk that is spun into threads using spinnerets. There is a wide variety of web sizes, shapes, and styles within the spider community. Below is a list of the common types of spiders found win North America:
Except for one herbivorous species that was identified in 2008, all spiders are predators. These beneficial insects hunt and feed on insects and other spiders, and some of the larger varieties hunt lizards and birds. (Yikes!) The familiar sticky webs are not the only way spiders capture their prey. Some species use a lasso, while others mimic their prey to get close enough to grab them, and others actually chase their prey down before injecting them with paralyzing venom.
After capturing a meal, spiders must inject victims with digestive enzymes, because spider guts are too narrow to process solids - they actually have filters on their faces that prevent solids from getting in! Some species of spiders form social groups of up 50,000 individuals, but most spiders are solitary. Most spiders only live for two years, but some captive species have lived as long as 25 years. According to Wikipedia, “Male spiders identify themselves by a variety of complex courtship rituals to avoid being eaten by the females.” (Sorry guys, I couldn’t resist.) Anyway, recent research has shown that spiders eat more than insects and other spiders: many species also drink nectar! And young spiders that eat pollen have been shown to have higher survival rates! Some spiders are scavengers, eating dead insects that they find. Captive spiders have even been observed feeding on egg yolk, sausages, milk, bananas, and marmalade!
Scary looking or not, spiders help us fight many garden pests without the use of chemical pesticides. In fact, spiders are believed to be the most beneficial insect we can have in the garden! Spiders commonly eat earwigs, roaches, flies, moths, mosquitoes, aphids, caterpillars, cucumber beetles, grasshoppers, crickets, pine sawflies, redhumped caterpillars, armyworms, leafhoppers, spider mites, thrips, leaf miners, spruce budworms, tobacco budworms, sorghum midges, and flea-hoppers. (It may have been easier to list what they don’t eat!) Spiders also eat other beneficial insects, but the damage they prevent far outweighs the damage they do.
Most types of spider venom are not dangerous to people, with the few exceptions listed below. In fact, research is being conducted to explore the use of spider venom as both pesticide and medicine. The possible medical uses of spider venom include muscular dystrophy, Alzheimer’s disease, erectile dysfunction, and stroke.
While spiders are a great addition to any garden or landscape, there are a few exceptions. Black widow, recluse, and funnel spider bites can cause life-threatening reactions. That being said, only 100 deaths occurred in the 20th century due to spider bites, while 1,500 people dies during the same time frame from jellyfish stings. Weird. Anyway, most spider bites are much like bee stings - they hurt like crazy, at first, and then go away. You can reduce the discomfort by cleaning the area, applying antiseptic, and then ice to the area. If unusual or severe reactions occur, get to the hospital as quickly and as safely as you can or call poison control (in California, that number is 1-800-222-1222). If you don’t have the number for Poison Control in your contacts, you should do that now. Really. I’ll wait. By the way, if you do get bit by a spider, try to capture it for identification. Your doctor will thank you.
If you see spiders in the garden, be glad for the help they provide. And consider this:
In the 16th century, monks would go out into forests and fields to collect spider webs to use to make gossamer canvases for religious paintings. (And we thought plastic wrap was hard to work with…)
I am okay with bugs. For the most part, I find them fascinating. I collect them, look at them through a hand lens or a microscope and then, depending on whether they are beneficials or pests, free them or feed them to my chickens. Centipedes have always been an exception, until recently.
Many years ago, I lived on Oahu, where centipedes get really big. When I say really big, I mean up to a foot long and over an inch wide! If that weren’t enough, centipedes can deliver a venomous bite that is said to feel like a bad bee sting. These prehistoric monsters will actually raise part of their body up, weaving in the air threateningly, and then chase you down a hallway. And they are tough! You can’t kill them by stomping on them in your sneakers. You need a hammer or a heavy duty coffee cup. Believe me, I speak from personal experience. The giant centipedes of the Amazon (Scolopendra gigantea) actually feed on lizards, mice, and even birds and bats that are caught in flight! Centipedes give me the heebeegeebees!
The tiny centipedes in my garden, however, are an entirely different story.
So what are centipedes?
Centipedes are not insects. Insects have three main body parts and three pairs of legs. Centipedes have segmented bodies and many, many legs. In fact, their name is Latin for hundred and foot, but they can have many more or less than one hundred. With all those feet, centipedes can move pretty darned fast. Can you imagine keeping track of all those feet? In 1871, Katherine Craster wrote The Centipede’s Dilemma:
A centipede was happy – quite!
Until a toad in fun
Said, "Pray, which leg moves after which?"
This raised her doubts to such a pitch,
She fell exhausted in the ditch
Not knowing how to run.
There’s nothing like overthinking to mess yourself up, right? Well, centipedes have evolved to grow each new set of legs a little bit longer than the pair in front. Scientists believe this is so the insects don’t trip over themselves, but the centipede’s first pair of legs evolved in a completely different way. They are venomous graspers, called maxillipeds, which are used to hold and inject their prey with paralyzing venom. Luckily for us, most centipedes are too tiny to pose a threat to gardeners in the field.
Centipedes can be pale grey, but mostly they are dark red or brown. Scientists estimate that there are 8,000 species of centipede. Only 3,000 species have been found so far and they are everywhere. There are even centipedes within the Arctic Circle!
Centipedes hide in leaf litter, under stones, and in logs. They lack the waxy cuticle, or outer layer, that most insects and spiders have, so centipedes lose water very quickly. They also do not have eyes in the proper sense. They can discern light and dark, but that’s about it. Most species of centipede hear and feel vibrations through their antenna.
There are five orders of centipedes:
Centipedes in the garden
The beloved garden centipede is completely blind. Its highly effective antennae has 14 segments that seem to make up for being eyeless. Being carnivores, your garden centipedes will spend their nights looking for insect larvae, soil-dwelling mites, baby snails and slugs, and worms. This puts them firmly in the category of beneficial insects, in my book.
If food becomes scarce, garden centipedes may also begin feeding on the roots of cabbage and other garden favorites, but this is usually the work of millipedes and not centipedes.
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!
Parsley - it’s not just for restaurants any more.
As a kid, I always turned a suspicious eye toward that sprig of greenery on my plate. My mother urged me to try it, so I did. Unfortunately, my young taste buds were not impressed. The mildly bitter bite of parsley was not my idea of delicious until many years later. Now that my taste buds are older and wiser, the refreshing tang of parsley adds a bright balance between flavors, cleanses the palette, and spices things up. If that weren’t reason enough to add parsley to a landscape, parsley packs one heck of a nutritional punch and, hey, it looks nice in the garden!
Parsley is a central Mediterranean plant, which means that it grows well in California, as long as it is protected from our scorching hot summers. Parsley makes an excellent shade garden or container plant. You can even grow it on your kitchen window sill for easy access and nice color if you have strong enough sunlight.
Parsley is related to celeriac and celery, which explains its Latin name (Petroselinum crispum), which means ‘rock celery’, but it’s a heck of a lot easier to grow than celery. Parsley prefers well-drained soil that is kept moist, but my plants seem to grow under just about any conditions. In spite of my heavy clay soil, I have several parsley plants that thrive under roses, trees, and shrubs. Research has shown that parsley also repels asparagus beetles, making it a good companion to asparagus and tomato plants.
Growing parsley does require some patience if you are starting from seed. Seeds should be planted 1/2 inch deep, 6 inches apart, and they can take 4 to 6 weeks to germinate. Germination rates are pretty high, so growing parsley from seed is the most cost effective method. While you’re at it, plant some extras and give young plants to family and friends as gifts!
In tropical areas, flat-leafed and curly parsley are grown as annual herbs. In more temperate regions like ours, parsley is biennial. Biennial plants take two years to go from seed to seed, but some of my parsley plants keep on growing for another year or so. In addition to leaf parsley, there is a variety called Hamburg root parsley (P. crispum radicosum). Root parsley is grown for the taproot, which looks, cooks, and eats like a white carrot. (I may have to try that!)
Parsley plants allowed to go to seed provide habitat, pollen, and nectar to honey bees and many other beneficial insets, some swallowtail butterflies, and even goldfinches.You will probably also end up with many free, randomly placed parsley plants next year!
If flavor and looks weren’t reason enough to grow your own parsley, the CDC says it’s a nutritional gold mine. They ranked parsley at #8 as a food that reduces chronic diseases, such as cancer, coronary disease, and osteoporosis. To learn more, check out the U.S. Dept. of Agriculture’s nutritional analysis website that allows you to look up the nutritional value of pretty much any food. Just 10 sprigs of parsley provides 22% of the RDA for Vitamin C and 200% of Vitamin K.
It’s pretty. It’s durable. It’s good for you. And it tastes good.
Where’s your parsley planted?
While walking across Spain last summer, I came upon an albergue (something like a hostel) where someone was using a riding mower. There wasn’t any grass, but the air was filled with a sweet, powerfully refreshing smell. Rather than caring for a lawn, this family had a yard filled with mint!
Now, mint is an amazing plant. It is crazy invasive and comes in many varieties. We’ve all heard of spearmint and peppermint, but did you know there is a chocolate mint? I have one growing in a leaky, handmade, stone pond that came with our property. Visitors are always amazed when I urge them to chew on a leaf - instant peppermint patties! I have also learned that there are apple, pineapple, orange, banana, and ginger mints. Needless to say, I am intrigued!
Mint is a member of the Lamiaceae family. This is a huge family, with over 7,000 species and people have been using mint plants for, well, forever! Mint a cousin to a surprising number of familiar herbs and other plants: basil, oregano, thyme, rosemary, sage, bee balm, lemon balm, lavender, savory, and even your desktop coleus plant and the mighty teak tree! Lamb’s ears, hyssop, self-heal, catmint, salvia, horehound, chia, skullcap, wild bergamot, and bugleweed are also members of this clan.
Most members of the mint family have square stems, small flowers, opposite leaves, and volatile oils that make them taste and smell so wonderful. If you look at any of the mint family flowers up close, you will see that they each have four stamens and five petals that are fused together, with two petals pointing up and three petals pointing down. Most mint plants are perennial.
Mint is super easy to grow. They love the sun, but can handle partial shade, and are drought tolerant. That being said, I find my chocolate mint plants, while nearly indestructible, prefer regular watering during the peak of our California summer. Because mint can be so invasive, you may want to try it for your own lawn replacement, or, for a more restrained planting, use mint in containers. I have found that mint is easiest to grow from cuttings. (If you live in the Bay Area, I am happy to share cuttings of my chocolate mint!). All you have to do is cover the cutting lightly with good soil and keep it moist until new roots start growing. Left to their own devices, mint plants will spread everywhere, using stolons, at or just below the soil surface. The real problem with mint is stopping it.
Mint juleps anyone?
Assassin bugs may not sound very friendly, but they can do your garden a world of good as they suck the blood from many plant pests.
Assassin bugs are a family of insect predators. They also take blood from mammals, but we'll get to that in a moment. The two most common assassin bugs are the leafhopper assassin bug (Zelus renardii) and the spines assassin bug (Sinea diadema). These long-legged beneficial insects are originally from the tropics.
Assassin bugs tend to be slender and colorful, with round, beady eyes. One feature that makes them easy to recognize (if you are foolish enough to get that close) is their needle-like beak with 3 segments. They use that beak to inject venom into their prey, often after laying in wait for the right moment. [These bugs belong in a sci-fi detective novel!]
The nymphs are frequently confused with leaf-footed bug nymphs. Both are slender and they tend to be pale brown, blackish, or red. The nymphs are only 1/4 inch long, so you may never see them. Adults can each 3/4 inch. You are more likely to see clusters of the brown, white-capped, barrel-shaped eggs on leaves and stems. The adults are clumsy fliers, but they are voracious feeders.
Assassin bugs will eat pretty much anything they can sink their beak into. They seem to prefer caterpillars, leafhoppers, and aphids, but they will also feed on other beneficial insects, such as lacewings, and blood from you and me!
Also known as Kissing Bugs, assassin bugs have been known to bite people, transmitting the microorganism that causes Chagas' disease. This usually only happens in rural central and south America, but, as with chickens, you should keep these critters away from your face.
Thrips may be really tiny, and they often disappear before you get a good look at them, but they can suck the life from plant leaves, growing tips and buds.
There are thousands of different varieties of thrips worldwide. A few of them are beneficial insects, eating mites and other pests, but most thrips are pests. They are commonly found in greenhouses. These species have piercing mouthparts used to puncture leaves and siphon out nutrient rich sap. Thrips are also vectors for other plant pathogens (diseases).
Thrips are really tiny - often less than 1/20” long. Thrips bodies are thin. They have fringed hairs on their wings, but you won’t see this without a hand lens. Adult thrips can range in color from white, yellowish, pale green, to brown or black. Immature thrips, both larvae and nymphs, look like tiny pale green caterpillars. To make sure that thrips are causing the leaf damage, shake damaged leaves while holding a blank sheet of white paper underneath. A magnifying glass can help identify the culprit. Yellow sticky traps can also help you detect the presence of thrips. If possible, identify the species attacking your plants. Watch this UC video to learn how to collect thrips for identification.
Unfortunately, thrips are difficult to control. Natural predators are your best line of attack, so avoid using general purpose pesticides. This will allow pirate bugs, green lacewings, and parasitic wasps to take care of the problem for you. Thrips have protective larval stages and the ability to fly away, so insecticides are not effective. A strong spray from the hose can displace many thrips. Also, removing weeds and surrounding plants can make life a little less comfortable for these tiny invaders. Once thrips have infested an area, reduce the amount of nitrogen or other fertilizers applied, to limit the amount of vulnerable new growth.
Preventing thrips infestations
Reflective mulch can confuse incoming thrips, but it won’t help once they are established. Row covers can also protect vulnerable plants. When pruning, avoid shearing susceptible shrubs, as this can provide many points of entry, both for thrips and other uglies. Be sure to deadhead flowers and remove dead or diseased tissue, as these areas can also provide a hiding place for thrips.
Healthy plants are better able to defend themselves, so be sure to irrigate properly to avoid water stress.
Most people really enjoy butterflies flitting through the garden. And what would a summer evening be without an occasional moth?
Generally speaking, these beneficial insects improve pollination and they are a sign of a healthy environment. Moths and butterflies (and their caterpillars) are prey animals to many predators, such as bats, birds, and lizards. The presence of butterflies and moths indicates a healthy level of biodiversity that translates into a healthier garden. The plight of the Monarch butterfly is a well known indicator of environmental problems.
Differences between butterflies and moths
The jury is still out on the exact difference between butterflies and moths. Skippers and butterfly moths muddy the taxonomic waters, but there are some clear differences (with several exceptions):
Lifecycle of butterflies and moths
In spite of the differences, butterflies and moths share the same basic 4-stage life cycle. Moths and butterflies start out as eggs, which hatch into caterpillars. These caterpillars are what cause most of the damage to garden plants. Caterpillars are voracious eaters! After they fatten up on garden plants, moth caterpillars spin a cocoon around themselves, while butterfly caterpillars form a chrysalis. Inside these tidy little protective packages, caterpillars are transformed into insects of the sky. [I just learned, watching BBC, that the Arctic Wooly Bear caterpillar may take 14 years to complete its metamorphosis and that it can survive being frozen solid!]
Moth and butterfly identification
A student at the University of Washington created a lovely animation of 42 North American butterflies. You can see it here. This is an excellent resource because it also shows range maps! Another great interactive tool can be found at Butterflies and Moths of North America.
Damage caused by butterflies and moths
While moths and butterflies won’t damage your plants, their caterpillars certainly will. This is especially true for the imported cabbageworm. During summer months, monitor plants for feeding holes, frass, and rolled or webbed leaves. Since moth and butterfly caterpillars are food to so many other critters, handpicking is the best treatment. Adding pesticides simply disrupts the natural controls already in place.
Lacewings are delicate, highly beneficial insects in the garden. Lacewing larvae are frequently called aphid lions, because of their voracious appetite for these tiny pests. Lacewings also eat small beetles, scale insects, caterpillars, leafhoppers, thrips, mites and small flies. There are nearly 2,000 species of lacewing worldwide, most of them occurring in North America.
Like many other predatory insects, lacewings lay eggs near aphid and other insect infestations. A single female can lay 100-200 eggs in her 6-week lifetime. The eggs are protected by being attached to white stalks that hang from the underside of leaves. Brown or yellowish-gray larvae emerge from the eggs and begin hunting right away. They feast for 2-3 weeks and then build a cocoon where they pupate into adult lacewings. In addition to many garden pests, adults also eat pollen, nectar, and honeydew made by scale insects and aphids. As they move through an area feeding, adult lacewings can help pollinate the garden.
Lacewings are most active during night and twilight hours. When lacewing larvae feed, they inject a digestive secretion that can dissolve the insides of an aphid in 90 seconds!
Lacewings are very susceptible to chemical pesticides. Rather than spraying chemicals in the garden, you can protect biodiversity by encouraging these beneficial insects. You can attract lacewings to the garden by planting (or tolerating) the following:
Eugenia are woody, evergreen flowering plants in the Myrtle family. Often found in landscapes as ornamentals, Eugenia’s glossy green leaves can become infected with the Eugenia psyllid (Trioza eugeniae). The Eugenia psyllid sucks plant juices from leaves and excretes honeydew that provides habitat for sooty mold. Introduced to California from Australia in 1988, Eugenia psyllid has become a serious threat to local landscapes.
Infected leaves look similar to peach leaf curl. This psyllid attacks new growth at terminal (end) points, leaving bumps and pitted areas. Leaves may also become discolored and appear red. Heavy infestations can cause the leaves to fall off (defoliation) and can kill a mature plant. Adult Eugenia psyllids are dark brown with a white abdominal band. Nymphs are yellow with orangish-red eyes.
Tiny, golden eggs are laid on leaf edges. Eggs hatch into first-instar nymphs, called crawlers, that feed on new growth. Nymphs pass through five instars before becoming winged adults. Mature Eugenia psyllids are only 1/10” to 1/5” long. They are related to aphids, but they have more powerful jumping legs and shorter antenna.
When Eugenia psyllid first arrived in California, the damage was so extensive that many home owners were forced to remove Eugenia plants from the landscape. In 1993, a parasitic wasp (Tamarixia dahlsteni) was released in Santa Clara County. This beneficial insect has helped bring Eugenia psyllid populations to manageable levels.
Since Eugenia psyllid nymphs prefer feeding on new growth, regular, frequent shearing can reduce infestations. Shearing is recommended at 3-week intervals during periods of new growth. It is important to leave the clippings on the ground, around the shrub or tree. This causes the eggs and nymphs to be on the ground, where they will die, while still providing food for parasitic wasps.
I hope this information inspires you to grow more of your own food. You can ask your garden questions on my Home page.