Protect your plants from a Heat Wave! Your system may be big like this one, or just as you need it, humble but perfect! Thanks to The Spruce for this great shade cloth image!
Take care of yourself!
While working wear that garden hat!
- Do your heaviest work early in the morning, as early in the day in possible, or in the evening…
- Slow down and pace yourself. Start slowly, pick up the pace gradually.
- Keep hydrated. You need water as much as your plants do. Drink more water than usual and don’t wait until you’re thirsty to drink more. Muscle cramping may be an early sign of heat-related illness.
- Wear loose, lightweight, light-colored clothing.
- Don’t forget the sunscreen!
- Tie a wet bandanna around your neck or even drape a wet cotton dish towel over the nape of your neck.
Temps in general are getting hotter. Know your area, like SoCal is in a drought area. It’s expected in summer, or it’s a hotter than average summer, or your micro niche is just a hottie and you know it! I watch the weather daily and a lot of my gardening choices depend on it.
Just a very long hot summer or a heat wave, here are some helpful pointers and things to know about how to get through it with flying colors and happy veggies! A few days of high temps is easier on your plants. Prolonged high temps is challenging for both of you. Sometimes there is also strong wind, high humidity, and high overnight temps.
Basic Garden Practices for areas that expect heat!
If you have a lot of heat generally, prepare your land with bioswales, shade trees and living wind breaks. Grow certain permanent heat loving plants that provide shade for the hot times. Plant them to the West to shelter more delicate plants from hot afternoon sun. If heat is a daily affair, install sturdy shade frames that can withstand substantial wind. See more ideas at Desert Veg Gardening
Well in advance, if you anticipate heat coming your way, select and grow heat and drought tolerant seeds, plants, flowers and herbs! Depending on your area, choose to avoid growing some plants in high summer. Plant in spring or fall instead. Some amazing perennials may be excellent choices. Chaya Tree/Tree Spinach and Tree Collards are two. Elizabeth Waddington writing for TreeHugger says ‘Remember, growing in rows in a traditional vegetable garden is not the only option. Perennial planting schemes like forest gardens can make your garden far more resilient, whatever extreme weather conditions climate change will bring.’
Perennials are always a winner because they don’t need to be planted/started over and over again, needing more start up water and waiting time for production. Many perennials can be harvested all year long! See more drought tolerant perennials at Grow Delicious and Amazing Edible Perennials!
Give your plants plenty of room! Space plants farther apart so they don’t compete for water and nutrients, which will help to reduce stress during periods of extreme heat.
From the get go, soil is always important because soil with a healthy amount of organic matter (about 5-9%) can make a difference in its ability to retain water. Gardens full of beneficial soil organisms also help plants tolerate periods of drought.
How you water is important! Long, slow that deeply saturates your soil. Usually you hear to let the soil dry so the roots will go deeper to seek water. Here’s the reverse: Water deeply so your plants can grow deep roots that can get moisture from more deeply in the soil during heat. Keep it moist routinely. Deep watering means you don’t need to water as often. Well watered soil maintains steady temperatures and is less likely to dry out.
Hand Watering Veggies?! YES! Plants have differing water needs. See more!
Consider planting IN furrows, not on top of them as is done in rainy country for drainage. Indigenous people worldwide have done this. New Mexico’s Zuni do this in a little more elaborate fashion with their Waffle Gardens. The berms around the planting areas hold in the water, act as windbreaks. The planting areas are ‘mulched’ with small stones. Stones were all they had in such a treeless area.
Anticipate!
For high heat, heat waves, wait to plant seeds. Seeds can be planted, but if time is not critical, it may be easier and more successful to wait. If you must plant, put up sturdy shade, wind and bird/animal protection. Be sure the setup is easy to water. In extreme hot weather, seed and nursery beds may need three or four waterings in the day, along with smaller raised beds and containers. Soil can dry out quickly, form a crust seedlings can’t get through. It must be kept moist. Decide if you want to keep this commitment, and don’t go on vacation!
This is a time when a nursery patch is the right thing to do, or raise them indoors. Rather than have scattered plantings, put them all in the same area so you can conveniently tend them all at once. Plant far enough apart to get your trowel in to safely transplant later. See Nursery Patch!
No stressing your plants by transplanting, pruning or fertilizing. Many plants save themselves and shut down production during temps 75° F to 95° F, but especially 85° and above, especially if the soil is dry. It’s common with vining plants. Most tomatoes drop flowers. They do set again when temps lower. But that means they aren’t going to take up a bunch of fertilizer either, since they are slowing their growth. Fertilizing signals your plant to grow and that’s the last thing we need. Better to fertilize a week or two before the anticipated heat wave. Otherwise, wait until after the heat wave when things have had a chance to cool down.
WEED before you mulch! Seriously, LOL! Those weeds will grow fast, just like zucchini, in all that heat. They will put down roots and eat your plants’ nutrients, drink their water, and bigger is harder to remove! Ixnay.
Heat! Plant IN Furrows, Mulch generously, eat Carrots! Image from FarmersAlmanac.com
MULCH! Deep enough, it stops light germinating weed seeds from growing and using water. Light-colored mulches help to reflect sunlight. Any Brassicas you are over summering really prefer cool soil. Load mulch on 6″ deep not touching the main trunk. Otherwise put on 2-4″ under other plants except super heat lovers like melons, squashes (maybe not zucchini), and pumpkins. Short rooted plants like cucumbers and beans need it. Depending on how closely your plants are planted, some, like strawberries and lettuces, may be self mulching and do fine without mulch. Besides protecting your soil, mulching keeps it cool, from drying out by reducing evaporation, reduces runoff and your need for water.
Harvest!!! Two very good reasons for this! 1) It unburdens your plant from having to work during the heat and uses less water. 2) Insects hatch hungry at various temps. One is the Leaffooted Bugs, Leptoglossus zonatus! In a cool summer in some areas you aren’t likely to see these pups. But if there are three to four consecutive 80+ hot days, keep watch, especially on your tomatoes! Depending on what area you are in, that can be anytime from April on. 80+ is standard for summer temps. In my near-the-coast in Santa Barbara, not at our foothills, Santa Barbara Community Garden photo archives, they were here in September each time. In our foothills they may occur in August. [In 2022 I think they arrived at our coastal garden in early August.] If these visitors are common in your area, pick all the ripe tomatoes ahead of time to save them. You can safely eat the bug bitten ones, but they aren’t pretty. See more!
Precheck all water systems to see they are working as you want during the heat wave. Set timers to once, twice a day watering and open devices to more water delivered! In case of power outages, have a backup system or be prepared to go manual.
- Install additional outputs? Maybe closer together.
- Make sure the water serves your plant out past its dripline. Keeping those surface feeder roots moist is critical. That’s where your plant uptakes most of its nutrients, water and oxygen! If those die, your plant goes hungry and produces poorly.
Homemade Shade Cloth cover over wire frame, custom fit! Keep in mind how well your custom shading structures will store after the hot time is over. Image at SquareFootGardening.org
Make shade with whatever you have if it is a temporary high temp time. Shade cloth, available at garden centers, blocks 15%, 30%, 40% to 100! Use it to shelter particularly precious plants or plants that will need it. Thin leaved salad greens may need 50-60% shade. Squash and beans do well with about 30%. If you use row covers be sure there is plenty of ventilation. Rig up a frame or hoop and spread the cloth over one side or the top usually works well enough. Anchor it well. Try not to lay it directly on the plants so they have air circulation. The temperature under the shade cloth can be 10 degrees lower! That 10°can keep plants alive and stop some plants from bolting! Use shade cloth over cold frames, cloches and greenhouses.
If you are vermicomposting, growing worms, you might want to move them into the shade or shade them well.
Some butterflies receive essential minerals and other nutrients by ‘puddling’ in very shallow water, so give them a helping hand during the dry weather by creating a puddling pool. Fill a dish with gravel, mud, water & some larger stones for butterflies to perch on & drink. From Surrey Wildlife Trust, UK
WILDLIFE! Expect wildlife to come to town for food and water. Set up safe watering stations. Put water for birds, butterflies, bees, little animals, in a predator safe place at your garden! Lay in sticks, stones, gravel, marbles in a shallow bowl so bees and butterflies won’t drown. Keep it filled. Check it every day. In a bowl, bucket, tub, trough, inside and out, put in a secure sloped wire ramp all the way top to bottom so small and tiny little ones like mice can get in and out as the water lowers. You don’t want them to drown and pollute what precious water there is. For birds, raptors to hummingbirds, place your station no closer than about 10-12 feet away from shrubs or natural coverage. This allows birds to keep an eye out for predators that might be hiding in the trees or shrubs. It also provides a safe place to escape to that’s close enough for birds to quickly take cover if they sense danger. Put out food if safe to do so. This is small payment for the things the creatures do for us!
Be sure the greenhouse water systems and vents are all in working order! If they are electric you might reset the vents to open a tad earlier, and more water is delivered more frequently. In case of power outages, have a backup system or be prepared to go manual.
What if you aren’t going to be home?!? This is the one time a knowledgeable reliable person is needed to keep check on things for you. Period.
If you are home, gather ye buckets of that shower water! Use it where and as needed. Install rainwater harvesting systems for times like these.
During a heat wave….
Water your soil not your plants! Water between the plants to keep surface feeder roots alive and feeding. From Homesteadandchill.com
Keep an eye on younger more vulnerable plants.
Keep watering! Check your garden every day. Watering is vital. Water in the morning when moisture is slower to evaporate, to give plants time to take up moisture before the worst heat. If necessary, water a 2nd time in the cooler evening. No midday watering when the sun is directly overhead to avoid sun scald to the leaves and fruits. In fact, conserve water by watering the soil not the plant! Water plants deeply, at least to 6 inches down. Keep them moist and evenly watered. Watch your plants. If they begin to droop, it’s seriously time to get out the hose. UNLESS it’s chard or squashes. They droop on schedule middays in normal weather. If you mistakenly over water, plants can literally drown. Put your finger in the soil to see if the soil is dry! Or dig down in the soil 1 to 2 inches next to the plant to see if it needs moisture. Disturb as few surface feeder roots as possible.
- Hanging baskets and containers will need to be watered more frequently than plants in the ground. Be sure to check them often. Stick your finger in the soil to see when it needs water. If they are small, pick them up. If they are light, water. Consider moving potted plants into a shadier spot during a heat wave. Benedict Vanheems at GrowVeg gives these wonderful tips: Container plants dry out very quickly and may need watering twice a day, especially if it’s windy too. Check that the water is actually being absorbed – you don’t want it just running straight down cracks between the potting soil and container wall. Continue watering until you see water running out of the bottom. You can use pot saucers to hold the water around your pots for longer.
- Check and maintain Wildlife watering stations
If you didn’t get to it before, lay down that mulch after you water!
Keep harvesting! Fruit left to linger on the plant uses more water than needed. Harvesting keeps your plant interested in production. If you don’t harvest, especially with the heat, it may think it is done and curl up its toes and be done itself. If you are wanting seeds, this may be a perfect time to let the fruits you have chosen to dry well.
Not to worry. Your plant is smart not to produce during the heat when it can’t support the fruit. Per Marissa Schuh: Depending on the variety of the vine crops, hot temperatures can change how many male and female flowers are present. Typically, high temperatures (over 90° F during the day and 70° F at night) develop more male flowers than female flowers. This means that we may be seeing zucchini plants with prolific flowers and few fruit, because the flowers we are seeing are all male, thus do not produce the part of zucchini we like to eat.
Elizabeth Waddington is so right! ‘And finally, when enjoying your garden, think about ways to make the most of your home-grown produce. For example, create some cooling cordials, smoothies, ice-creams, or ice lollies [lollipop or Popsicle in the US] using the fruits and berries (and even vegetables and/or herbs) that you grow.’
After the heat wave! YES!
Reset all your water systems timers, frequency and amount, and the greenhouse water settings and vent timers. Check the Wildlife watering stations for water quality, enough water, and enough mud for the butterflies.
If the heat is not permanent, carefully store your shade devices. You may need them again. Make notes on discoveries or improvements to be made before next time. Put it on your projects calendar and attach detailed notes to the materials.
Check on mulch plant by plant. Some may still need it. Others may need it removed if it is late summer, fall approaching, days shortening, back to cooler nights and evenings. Mulch can cool your soil and shorten your season prematurely.
At left is neon pink Chard bolting. The leaves are still edible!
Expect Bolting! It is simply your plant putting up a flowering stalk to make seeds for the next generation. It is common at strong weather changes. When it has been cool, and heat comes on, your plant thinks it just had summer, so sends up a seed stalk! When possible, select bolt resistant seeds and plants. Day length may be part of bolting. Bolting! Select the right day length plants per season and your latitude! See important details about Photoperiodism.
Harvest any seeded fruits that have dried sufficiently for seedsaving. Have your seedsaving gear and storage jars handy! If you are preparing for January seed swaps, have your envelopes ready to label. More on SeedSaving!
Many times there is an after-the-heat-wave storm! It can be mild or a deluge! Good idea to wait and see a few days before planting seeds. If it has been a late summer heat wave, after such a storm it may be the perfect time to get fall seeds and transplants in!
Long term choices may be very meaningful in these times of planetary change!
Greg Seaman founded Eartheasy in 2000 out of concern for the environment and a desire to help others live more sustainably. He combines his upbringing in the cities of New York, Boston and San Francisco with the contrast of 40 years of living ‘off-grid’ to give us a balanced perspective on sustainable living.
July 2019 he said ‘Heat waves usually are of short enough duration that gardeners can manage to produce successful crops. Prolonged heat waves, of course, are more challenging and crops may be stunted or crop yields reduced. Unfortunately, the long-term outlook for our climate indicates that in upcoming years we gardeners will need to hone our hot weather gardening skills. The measures described above will likely be common knowledge in the years to come.’
If you have lived in the desert for any length of time, you have found ways to live there successfully with extreme temps and wind. As a gardener you probably select the toughest seeds of plants that survive these hot/cold and drying conditions. You may have installed bioswales and living wind breaks that also provide shade, and you are likely using indigenous techniques like the Zuni waffle Gardens that have improved your soil and output, cut water costs and plant losses. See more on desert veg gardening! You lowlander coastal gardeners may modify and incorporate some of these useful tips to your own needs.
2021! Here is Curtis Quam’s waffle garden in action! He tends it with his family at Zuni Pueblo, NM. It uses less water, increases food security!
May you and your garden be blessed no matter how hot or long the heat!
Updated 9.10.22
Love your Mother! Plant bird & bee food! Think grey water! Grow organic! Bless you for being such a wonderful Earth Steward!
The Green Bean Connection started as correspondence for the Santa Barbara CA USA Pilgrim Terrace Community Garden. Both remaining Santa Barbara City’s community gardens are very coastal. During late spring/summer we are often in a fog belt/marine layer most years, locally referred to as the May grays, June glooms and August fogusts. Keep that in mind compared to the microclimate niche where your veggie garden is. Bless you for being such a wonderful Earth Steward!