Know what doesn’t love the hot, humid month of August? Your stressed garden plants

Ask people in the Midwest to name their favorite month, and the answer is seldom August. Typically, it’s hot. It’s very hot. And it’s humid.

What issues do heat and humidity cause? Outside of the standard environmental stresses of drought-stricken plants, sunburned fruit, steamed leaves and crusted-over soil, the combination of heat and humidity create what can quickly become a breeding ground for pest and pathogen outbreaks. Both insects and fungi need warmth and moisture to thrive. When these two factors increase exponentially, combined with environmental stresses, disaster may be looming.

This is where your mechanical or physical maintenance practices can come into play and help you. While you may not be able to control the weather, you can still influence how the weather affects your garden.

You will want to be sure that when you water, you do not use overhead irrigation. Instead, apply water directly to the ground to be absorbed by the roots. This prevents water accumulation on the plant itself, decreasing the likelihood of disease development.

Mulching your gardens will benefit you by preventing splashing during watering — another factor that can lead to disease spread via fungal spores. Mulching keeps consistent soil moisture on your plants and allows for less frequent watering. It will even stop the soil from crusting over, which keeps oxygen flowing to the plants’ roots.

Even the simple practice of pruning and thinning your garden plants can benefit pest and disease prevention. By removing some of the plant matter, you are increasing airflow. This, in turn, decreases microclimate humidity and therefore reduces disease. Also, you are creating a less hospitable environment for insect pests, as they have fewer hiding spots from predators or the elements.

With less plant matter to support and keep alive, your plants can allocate more resources to the parts you retain. This will result in larger and healthier crops at the time of harvest.

The answer to most pest and disease control challenges in plants, even outside of times of extreme heat and humidity, is simply prevention.

By maintaining healthy soil, rotating your crop growing locations, weeding, pruning and adding physical supports — all while supplying proper light, water and nutrients — you are encouraging healthy fruit and vegetable crops. Healthy, vigorous plants have the most success at fighting off those pesky insects and diseases.

If pests do appear in your gardens during this most-inhospitable part of the growing season, the plants will be in their best shape to fend them off and ensure a productive harvest.

Anthony Reardon is a horticulture agent with Kansas State University Research and Extension. Need help? Contact the Johnson County Extension gardening hotline at 913-715-7050 or email garden.help@jocogov.org.

This story was originally published August 11, 2023 at 6:00 AM.