Credit: AdobeStock/Ronstik
Temperatures have been unseasonably cool in recent weeks, but a heat wave can be just around the corner. Heat and drought pose serious challenges to vegetable plants. Common issues include sunscald, wilting and dehydration. Consistent hot weather can cause flowers to wilt and drop off, and unprotected tomatoes can literally cook in their skins. However, there are several steps you can take to help your garden thrive despite the heat.
Healthy soil is key
The healthier the soil, the stronger the plants and the better they can resist the harsh effects of excessive heat. Add plenty of compost and organic fertilizer in the spring, and test the soil to ensure a recommended pH of 6.5.
Early harvest
Before a heat wave hits, thoroughly harvest all that’s ready, even if it’s a little young. Less stress on the plants means they’ll fare better in extreme conditions.
Mulch, mulch and more mulch
Mulch is crucial. Use straw, grass clippings, cardboard and leaves to create a barrier between the sun and the roots. Mulch at least 3 inches deep holds in moisture, keeps the soil cool and suppresses weeds. Weeds, unlike your vegetable plants, thrive in hot and dry conditions.
Shade cloth for cool-weather crops
Cool-weather crops like lettuce, beets and cilantro benefit from a shade cloth, which still allows adequate light through. A bed sheet can also work. Use PVC pipes bent into arches for support and secure the cover firmly. For tall plants like tomatoes, use binder clips to attach the cloth to tomato stakes. A shade cloth can make it up to 15 degrees cooler for your plants.
Watering essentials
Even a light shower isn’t enough to keep your plants alive during high periods of heat; there needs to be steady rainfall for at least six hours to make a difference. Use the finger test: Dig down the length of your finger in the soil. If it doesn’t feel moist, water each plant with at least a gallon of water. Drip irrigation on a timer is ideal if you can afford it.
Container plants
Grow bags and pots dry out even faster. Move them to a shady area and water around the edge of the container — that’s where they dry out the most. Collect rainwater, as plants prefer warm rainwater over cold well water. Distribute it soon before mosquitoes lay eggs in it. Water at least once a day, or every other day if using mulch. Watering in the early morning is better than in the evening because it gives plants a chance to dry out and reduces the risk of fungal growth. Water along the soil and only mist the leaves. For deep-rooted plants like tomatoes and potatoes, water slowly for about 10 minutes per bed.
Pruning and fertilizing
During an unusually hot summer, avoid heavily pruning your tomatoes. Their fruit needs some shade from the leaves to prevent sunscald. Never fertilize during a heat wave, as asking plants to produce new growth will stress them further.
Take care of yourself
Work only in the early morning or evenings, wear a large-brimmed hat and light-colored clothing, and stay hydrated. Use the hose to cool yourself down and wear a wet scarf around your neck. If you start to feel too hot or dizzy, stop and go inside. A healthy plant will eventually recover from heat stress, even if not tended to every day.
Stay cool, everyone!