Gardening in Extreme Heat
By Tanner Wycoff, editing by Nancy Vaughan
Tanner Wycoff is the Birdhouse.farm gardens, pasture, and forest designer. Our team asked him how gardeners that were so “burned” with last summer’s excessive heat can respond this spring. Last year many people were unable to grow normally reliable crops (like tomatoes, a staple in Kansas) and many folks are wary about spending time and money into their gardens this year. Here is what Tanner came up with…
As summer temperatures become more erratic, gardeners across the United States are getting unreliable results from their gardens. Luckily there are a few things you can do about this.
Look to the tropics
Many heat-loving tropical crops can be grown as annuals in temperate gardens.
Water Spinach aka Kang Kong: an edible, semi-aquatic plant that is in the morning glory, not spinach, family
Moringa: a fast-growing deciduous tree with edible leaves, seed pods, fruit, and flowers. Moringa is rich in protein and glucosinolates, as well as many other nutrients.
Malabar Spinach: like water spinach, this plant is not a true spinach, but is in the mallow family and is very nutritious.
Katuk: also known as Sweetleaf, this is a shrub with edible shoots, flowers, fruit, and seeds
Chili Peppers
Sweet Potato
Mexican Tarragon: an edible herb in the aster family with a strong flavor similar to French Tarragon, or Licorice
Okra
Red Roselle: a hibiscus that produces edible calyx, that can be used to make tea, smoothies, or as an addition to salads
Sissoo spinach: a good edible ground cover.
Okinawa spinach: not a true spinach, but the leaves can be eaten raw or cooked and are extremely nutritious
2. Water appropriately
Water two to three times per day with misters or sprinklers during the hottest part of the day in hot weather. Water on the surface of plants cools the plants as it evaporates. Water plants enough that they are moist for the hottest part of the day but dry before the sun goes down.
Water your plants heavily and let the soil dry out in between waterings in average or warm weather. When you water your garden heavily it allows water to penetrate deep into the soil. This will stimulate the plant to grow deeper roots in order to access water and nutrients deep in the soil.
3. Include trees and other perennials
Heat-tolerant trees and perennials such as jujube, mulberry, grape, asian pear, goji berry, and persimmon are able to survive harsher conditions once established. Trees generally take two to ten years to bear fruit, but once they do, they will produce for five to one hundred and fifty years.
Perennials help build up organic material and beneficial organisms that hold water and nutrients in the soil.
Trees provide landscapes with protection from extreme weather like floods, hail, and wind.
4. Plant hardy varieties
Some varieties of crops are able to handle hotter weather than others. Some examples include heatmaster tomatoes, thai chili, or eramosa potatoes.
5. Consider the wind
Wind can both help and harm your garden.
Cool breezes can help cool your plants on hot summer days.
Hot winds can dry out your garden and kill your plants. Keeping your plants well-watered and sheltered from direct wind can help protect them from hot summer wind.
Wind and airflow in general helps to reduce pests and disease.
6. Use an acceptable amount of shade for the crops you're growing.
Shade cloth
Shade cloth is an opaque fabric that helps protect plants from the sun.
Shade cloth can be moved as needed, or put in storage after hot weather passes.
Shade from trees and other plants.
Green shade from plants is up to 50% cooler than shade from an inanimate object.