Keeping the plants in your garden well-hydrated is crucial to keeping them alive during extremely hot weather. When temperatures approach triple digits, your plants need extra care. Remember, flowers and vegetables grown in containers dry out quicker than those planted in the ground.
Plants lose moisture through the pores in their leaves. It’s normal for leaves to droop during periods of high heat. Drooping minimizes water loss through evaporation by reducing the surface area of the leaves. When the temperatures go down, the leaves will perk back up.
Don’t confuse drooping with wilting. If your plants are wilting, they’re dying. This is an emergency that requires immediate attention. Water wilting plants thoroughly, right away. When conditions are harsh, think of your garden as a hospital emergency room. Triage is the order of the day.
Annuals and vegetables in raised beds or containers must be watered at least daily. Hanging baskets may need to be watered twice a day. If time is an issue, perennials and shrubs should be hardy enough to go a couple of days between watering. Focus solely on the tasks necessary to get your garden through the heat. Now is not the time to worry about weeding or pruning.
Using mulch in your garden is one of the best things you can do. Mulching serves several purposes. First, it helps with water retention. Mulching slows moisture loss by reducing evaporation. It also helps to moderate soil temperatures in the root zone, keeping plants cool. Additionally, mulch acts as a physical barrier that keeps fungal spores from splashing onto the leaves during rain or irrigation. Plants under heat stress are more susceptible to diseases. The pressure from multiple stressors may be more than they can handle. Finally, mulching suppresses weeds that also compete for any available moisture. A three- to four-inch layer of organic material is needed for mulch to be effective.
Growing tomatoes can be challenging during periods of excessive heat. Two of the most common heat-related issues are cracking and blossom end rot. Cracking in tomatoes results from excessive rain or irrigation following a period of drought. When tomatoes are watered after they have gotten too dry, they absorb the water quicker than their skins can expand. This rapid increase in the internal pressure of the fruit results in split skins. To prevent this from happening, water your tomatoes on a regular basis and don’t let them get too dry. Cracking usually occurs in mature tomatoes because their skins are no longer growing. Once watering has been regulated, subsequent fruits shouldn’t be affected. Remove cracked or split tomatoes from the vine immediately. They attract insects and diseases.
A dark, leathery, rotting spot on the bottom end of tomatoes is called blossom end rot. This isn’t a disease. It’s the result of a calcium deficiency. Since there is generally plenty of calcium in our soils in Kansas, it’s usually caused by drought or fluctuations in soil moisture. It can also be caused by excessive growth of vines and leaves. Blossom end rot can’t be cured, but you can fix the causes. Regular watering and the proper use of fertilizers usually does the trick. There are fertilizers formulated especially for tomatoes. Follow the directions carefully. Too much nitrogen causes excessive vegetative growth. Blossom end rot results when the plant grows faster than its ability to effectively absorb calcium.
Excessive heat can adversely affect the gardener as well. Be sure to drink plenty of fluids. Avoid working during the hottest time of day. Minimize exposed skin and wear plenty of sunscreen. Wear a wide brimmed hat that covers your eyes and ears. Make sure to take plenty of breaks.
As much as we love our gardens, there’s nothing worth risking our health and safety.
Rachel and Ivan Minnis are avid gardeners. They live in Leavenworth. For more information, visit The Minnis Rose Garden on Facebook. Contact them at firstname.lastname@example.org