Greens bolt and wither
Searing heat and glare above
Seek shade and cool water
July can get too hot to spend much time outside. Early morning and late evening make working in the garden far more comfortable, but leave most of the heavy work to the plants as they produce leaves, stems, and fruit in response to all that sunlight. The best things you can do for your garden in July is irrigate properly and monitor plants for pests and diseases.
Monitoring for pests and diseases
You know what they say about an ounce of prevention. Well, here are a few helpful July ideas that work to prevent problems in the garden before they have a chance to get started:
It’s all too easy to forget about the trees in your landscape, but scorching summer heat and an extended drought can be devastating. Trees are a big investment of time and space, so be sure to include them in your watering plan. The only exception is California live oaks - they are accustomed to hot, dry summers and watering them only makes them susceptible to disease.
There is no fixed magic formula for watering plants in the garden. There are simply too many variables, such as plant variety and age, soil structure, feeding practices, sun and wind exposure, overall plant health and life stage - you get the idea. The best way to assure that your garden plants are getting the water they need is to learn as much as you can about the specific varieties and their water needs. This information will help you to provide them with the growing conditions they need. Be sure to water tomatoes, peppers, eggplant, and squash consistently, to avoid blossom end rot.
During summer, container plants may need a drink practically every day. Just be sure to avoid overwatering - a drowning plant looks an awful lot like a plant that’s dying of thirst. An inexpensive moisture meter ($10-15) can help prevent irrigation errors. Also, be sure to get those containers up off the concrete. Even the smallest air space underneath can significantly reduce temperatures for potted plants.
If you still have a lawn, be sure to raise the blade on your mower. Taller grass shades the ground, reducing water loss and stabilizing soil temperatures. By the end of July, your lawn will probably be brown, and that’s okay. Keep watering it. The root system will stay alive, and green shoots will come back in the fall after temperatures go down. [I use water from my washing machine with no negative results and my lawn stays green far longer.]
Basil and other heat lovers
It is finally warm enough for crops such as basil, melons, eggplant, and peppers to really thrive. These are some of my favorite plants. You can train melons up a trellis or ladder, and you can never have too much basil. If you have more than you can use fresh, simply whip up a batch of pesto and throw it in the freezer. Come January, you’ll be glad you did!
Mulch and top dressings
Summer is an excellent time to mulch unused garden areas. As it breaks down, the organic material will improve soil structure and add valuable plant nutrients. This is particularly helpful if you have compacted soil. Until it does break down, mulch stabilizes soil temperatures, reduces weed competition, and helps soil retain water. In the same way, top dressing the plants in your garden or foodscape with aged compost is a trouble-free way to add nutrients to growing plants without applying chemical fertilizers.
Fire safe gardening
Summer fires can be devastating, but you can slow the spread of fire with fire safe gardening. Rural areas of California and other states are required, by law, to maintain a defensible space around homes. You can use the same ideas to protect your home and family:
And leave the fireworks to the pros.
As you lounge in the shade with an iced tea, remember that July is an excellent time to consider what cool season crops can be added in fall!
Longer days of sun
Burst forth fruits and leaves
June is a busy month in the garden. Rising temperatures and strong growth increase the need for irrigation. Sowbugs and other pests seem to be everywhere. Fruits, flowers, and mulch are the name of the game when it comes to June garden chores.
Bees are everywhere you look, collecting pollen and nectar for their families (and pollinating nearly all of our garden crops). If you see a swarm, don’t panic. Swarming bees are surprisingly docile. Their bellies are full of honey and they are simply looking for a new home. Contact your local Bee Guild or Master Gardeners for information on swarm collection. Under no circumstances should honey bee swarms be sprayed with insecticides.
QUARANTINE WARNING: MOST OF SANTA CLARA COUNTY IS UNDER QUARANTINE FOR CITRUS, DUE TO THE ASIAN CITRUS PSYLLID. CHECK THIS MAP TO SEE IF YOU ARE AFFECTED.
June usually provides an abundance of fruit. If damaged fruit is seen, take a closer look. If the fruit looks chewed on, it’s probably rats or squirrels. Personally, I use Bobbex-R to deter these destructive, disease-carrying pests. My dogs enjoy helping out, too! I also use traps to kill rats. It’s a bit disgusting, but it works.
Fruit drop and fruit thinning
Don't be concerned if your fruit trees suddenly drop a majority of their blossoms or immature fruits. This normal behavior, called June drop or blossom drop, prevents trees from producing more fruit than they can support. To help your trees create the highest quality and best sized fruit, this is the time to thin fruits.
If you haven’t already, June is a good time to check irrigation systems for leaks. Drip systems should be flushed and emitters checked for clogs. This is also a good time to test to see where, exactly, sprinklers are spraying and where they are not. There’s no sense in wasting precious water in urban drool and the spray should never hit tree trunks.
Mulching is one of the best things you can do in the garden, especially in June. Mulching stabilizes soil temperatures, reduces weeds, and helps the soil retain moisture. Aged compost, placed on top of the soil, is mulch. Tree trimmings make excellent mulch and they can be acquired for free from tree trimming companies! As mulch breaks down, it adds valuable nutrients to the soil and improves soil structure. Just make sure that mulch is kept away from tree trunks and that it isn’t too thick. Generally speaking, a layer of 3 inches is just right. Too much mulch can interfere with gas exchanges.
If you haven't started already, June is an excellent time to plant those heat-loving cucumbers, peppers, squashes, tomatoes, eggplants, and melons. Also, you can create an ongoing harvest by succession planting radishes, beans, and other determinant crops.
Be sure to put on your sunscreen, wear a hat, and keep those tools clean and sharp as you enjoy the garden in June!
April chirps and sings
Splitting shells and seeds and blooms
April is a busy month in most gardens. With scorching summers on a not-too-distant horizon, flowers, weeds, and everything else seem to be striding toward sunlight. Cool nights may hold this rampant growth in check for another week or two, but most gardeners have plenty of April garden tasks to keep them occupied.
It’s planting time!
Temperatures are nearing or have reached the point when gardeners can plant most herbs, leafy greens, and vegetables. Lettuce, arugula, spinach, bok choy, basil, parsley, cilantro, and radishes can be planted every couple of weeks in succession for a continuous harvest until temperatures get too hot.
In warmer regions, potatoes, bush and pole beans, corn, cucumber, summer and winter squash, and tomato seeds can be planted now. Be sure to read packet directions for planting depth, spacing, and sun requirements for the best results. [If you haven't already, email me for a customized planting chart based on your USDA Hardiness Zone.]
Codling moth larvae can devastate apple, plum, pear, and walnut crops. The larvae pierce the fruit and burrow into its core, where it then feeds on the fruit, making it inedible. On apples, look for tiny dimples with a small hole in the center. These holes are usually filled with frass (bug poop). Trees should be monitored every week for signs of infestation. Infested fruit should be removed and discarded, to break the codling moth life cycle. Pheromone traps can be hung in isolated trees, but you need to understand that these traps attract codling moths to the tree. The traps are really a population monitoring device, not a control measure. Fruit can be bagged for protection, but this is a very labor-intensive method. Kaolin clay application is an excellent organic control method. Heavy infestations may require the use of pesticides before fruit is affected.
As flowers begin blooming, you can increase production by removing spent blooms.This works equally well for roses and artichokes. Take a look at buds further down the stem and clip just above a bud that points in the direction you want the new growth to go. Deadheading can help the plant structurally and it allows for good airflow, as well as stimulate new flower development.
Spring rains bring moisture that can cause many fungal diseases. Anthracnose, brown spot, powdery mildew, sooty mold, and verticillium wilt should all be watched for and treated. Many of these conditions can be avoided with pruning that allows good air flow and irrigation that does not come from overhead. Overhead watering splashes millions of fungal spores onto uninfected plants, spreading the disease (plus, it wastes water through evaporation).
Irrigation & greywater
As temperatures rise, irrigation becomes more important. Containers and raised beds will begin to dry out and need to be checked every day. If the irrigation system wasn’t inspected in March, be sure to do it now. Greywater, from sinks, washing machines, and rain barrels can be used to irrigate ornamentals and lawns. I also use water collected from the shower, as it heats up, to water edibles.
Before you get too excited about planting, take a few minutes to inspect your property for mosquito breeding grounds. Mosquito larvae can grow in as little as one tablespoon of water. Birdbaths, rain barrels, clogged rain gutters, and planter pot saucers can all harbor these pests. Mosquito dunks, also available as granular bits, contain a bacteria, Bacillus thuringiensis israelensis (Bt.i), that is deadly to mosquito larvae but harmless against all other living things. You can also use Bt.i against fungus gnats. Mosquitofish can also be used to reduce mosquito populations.
To add nutrients, reduce weeds, and help retain moisture, nothing beats mulch. Wood chips and aged compost both make excellent mulch. You can request free arborist chips from local tree trimmers. To stop weeds from growing, the mulch should be 4" to 6” thick. I used to recommend a layer of cardboard or newspaper be placed underneath, but then I learned that these materials attract termites and voles. Cardboard also slows gas and water exchanges. Be sure to keep mulch at least 8” away from tree and shrub trunks, to avoid fungal diseases, such as crown rot and butt rot.
If you have navel orange trees, the crop will be ripening in April. Oranges left on the tree too long will dry out and become inedible. Instead, harvest the entire crop by the end of the month and you can make my new favorites, Cardamom Orange Marmalade, Orange Cumin Chutney, and Spiced Oranges. Once canned, these delicious condiments make lovely gifts. You’ll want to be sure to save plenty for yourself - it’s that good!
Valencia oranges will ripen during the summer and they make excellent juice. April is a good time to add nitrogen for orange trees. One-year-old trees will need 1/10 of a pound of nitrogen, while mature trees need approximately 1-1/2 pounds. These amounts should be divided into three different feedings in April, June, and August. Blood meal is an excellent source of nitrogen, without all the fillers.
QUARANTINE WARNING: MOST OF SANTA CLARA COUNTY IS UNDER QUARANTINE FOR CITRUS, DUE TO THE ASIAN CITRUS PSYLLID. CHECK THIS MAP TO SEE IF YOU ARE AFFECTED. ALSO, BE ON THE LOOKOUT FOR ORIENTAL FRUIT FLIES. IF EITHER PEST IS SEEN, PLEASE CALL THE PEST HOTLINE AT 1-800-491-1899.
Fennel, rhubarb, and asparagus, as well as fruit and nut trees, provide many years of food production and April is a good time to plant. These plants will take up a good amount of space, so be sure to keep mature sizes in mind.
Plum bud gall mite
As of January 2019, we have a new pest in northern California. Be on the lookout for abnormal growths, or galls, on almond, apricot, plum, pluot, and other fruit and nut trees. These tiny eriophyid mites are only 1/100th of an inch long. If you have a 20x hand lens, you may be able to see them. They can be translucent yellow, pink, white, or purple, with two pairs of legs up near the head. You are more likely to see galls on new shoots and fruit spurs that plants produce in response to these invaders. This new pest threatens tens of thousands of fruit and nut trees in California. If you suspect plum bud gall mites on your trees, please contact your County Extension Office right away.
This is also a good time to replace last year's sticky barriers. The protection from crawling insects that these simple barriers provide cannot be overstated. Sticky barriers block those crawlers (and slugs and snails) from getting up into your fruit and nut trees. This is especially helpful when it comes to ants, which will protect and farm aphids. Over time, the goo dries, making it ineffective. Also, the tape tends to pull away from the trunk, creating an easy trail for pests. Gently remove the old tape, inspect the trunk, and apply a fresh sticky barrier. Just be sure that you do not use painter's tape to create sticky barriers. The moisture from the goo will cause the tape to disintegrate and damage the tree's bark.
As difficult as it may be for gardeners to thin out fruit and young plants, it really is necessary for the optimal growth of the remaining plants. April is the time to thin fruit on fruit trees, such as apricots, peaches, apples, pears, nectarines, and plums. Crowded fruit doesn’t get as big as it could and it encourages fungal diseases. Close-quartered fruit also provides great hiding places for pests. The best fruit grows from strong flower buds in full sunlight. The basic rule of thumb for thinning fruit is to leave one fruit per spur, with fruit 4-6” apart. Apricots, nectarines, and peaches are normally thinned when the fruit is 1/2-3/4” in diameter. Nut trees do not need to be thinned. Seedling plants should also be thinned according to seed packets or other reputable information. This allows each plant to reach its full potential and reduces problems with pests and diseases. Rather than pulling seedlings out by the roots, snip them off at soil level. This reduces disruption to the remaining (delicate) root systems and leaves valuable soil microorganisms in place.
Tree Trunk Painting
If you didn’t whitewash your tree trunks (and exposed branches) in March, there is still time to provide this valuable sun protection. Trunks and branches that get too much sun exposure can be damaged, causing the bark to split and peel. This provides pests and diseases with easy access to your trees’ inner workings. A simple mixture of half water and half white interior latex paint is all you need to protect your trees from sunburn this summer.
One of the most important April garden tasks is to get rid of those weeds. Since they can go to seed faster than everything else in the garden, removing them now will save you countless hours of work later on, in the summer.
Nascent roots and stems
Displace freshly warming earth
Chill nights slow their birth
March in California is the envy of the East Coast. Still bundled against blizzards, they hear about our sunny days and emerging blooms as they look out at a sea of snow. But don’t be fooled by all the new plants breaking ground.
My last frost date is March 15th, but we’ve already reached temperatures as high as 80°F! To tender young shoots and first leaves (cotyledons), a sudden drop in temperature can be deadly. As tempting as it may be to trim away frost-damaged plant parts in early March, it is a good idea to wait until closer to the middle of the month, just to be on the safe side. Fret not, however, there are many tasks to keep you busy in the garden in March!
Citrus pruning should not be started until after March 15th, but now is the time to seriously inspect for mummies. Mummies are those shriveled up, fuzzy gray oranges that house millions of fungal spores. When removing mummies, try to disturb them as little as possible, or cover them with a plastic bag before removing them from the tree. If a citrus tree shows signs of chlorosis (yellowing) on older leaves, it may indicate a nitrogen deficiency. Interveinal (between leaf veins) chlorosis usually means a micronutrient, such as iron or manganese, is needed. Our soil tends to be very low on iron, but you can’t know for sure without a soil test. After the danger of frost has (nearly) completely passed, on March 15th, give citrus trees a good pruning. Just be sure to keep a lookout for bird nests. It’s that time of year!
Walking on wet ground causes soil compaction. This is especially true for areas with heavy clay soil. Rather than walking on wet soil, stay on paths, install stepping stones, or just wait for it to dry. Compacted soil is particularly difficult for young roots to move through, and it can cause drainage problems. Also, digging wet soil damages soil structure. The best treatment for compacted soil is a thick layer of free arborist wood chips. Amazing things happen under mulch!
Winter and spring moisture provide the perfect habitat for many pathogens. You can prevent diseases, such as fireblight on apples, pears, quince, and loquat, with fixed copper sprays. You can also reduce the chance of powdery mildew on grapes by applying sulfur at this time.
Feed young trees
As young trees continue putting out new roots, shoots, and leaves, they will benefit from being fed in March. Check the specific species of tree for more information on how much fertilizer should be provided. Since my soil tests indicate that everything is present in abundance, except for nitrogen and iron, those are the only two I add. Money saved. Environment protected. Check.
Another common March task is to inspect and repair sprinklers, drip systems, and water collection systems. How do you know if you have an irrigation leak? It can be difficult to spot, especially if it is small. The most common indication is an area that gets and stays wet or green longer than everywhere else. Sprinklers should be aimed so that they do not hit tree trunks, walkways, driveways, or sidewalks. The former can cause fungal diseases and the latter creates wasteful urban drool.
March is also a good time to prune out dead branches and twigs from fruit and nut trees and ornamental trees and shrubs. It is easier to see the structure of each plant before it is covered with leaves. The only exception is those trees susceptible to Eutypa dieback. Pruning grapes or stone fruits, such as apricot or cherry, before the rains are completely over can create an opportunity for infection. I know it's hard to wait, but you should.
Slugs and snails
Our warming temperatures and moisture work together to create the perfect habitat for slugs and snails. These mollusks can devastate seedlings in a single night, so be prepared. I urge you to follow the link to slugs and snails to learn more about the specific ingredients in different bait products. They are not created equally, and some can harm pets. Choose accordingly. Be on the lookout for pillbugs, too.
If you have not conducted a soil test recently, now is the time. Find out what is in your soil before you start adding plants or fertilizer.. This will help avoid nutrient imbalances that can wreak havoc on plant health.
Walk through your garden in March and you are sure to see weeds coming up in every location imaginable (and a few unimaginable places!). Your Number One March garden task is weeding. Since some weeds can go to seed in as little as a week, now is the time to cut them off at ground level with a hoe. Wait until later in the season and thousands of seeds will already be sown. Healthy weeds make great additions to the compost pile. Personally, I feed them to my chickens.
Enjoy the early blossoms!