Dealing with okra/cotton root rot

Linda Workman Smith
Multi-County Master Gardener Association
Wheat to be tilled under

Hello, readers. As you may — or may not — have noticed, I took last summer off from writing gardening articles; Sweet Hubby was “indisposed” for several months so I had to take up some of the slack here at our Two Acre Paradise/Three Dog Circus for a while.

In the summer of 2019, I noticed that my okra plants exhibited a condition heretofore not present in my gardens. After researching, I concluded it was okra/cotton root rot. It was late in the season so I didn’t give it much thought.

Then in 2020, dealing with Sweet Hubby’s chores as well as my own, in my haste to get my garden planted, I didn’t give crop placement much thought. As luck would have it, after planting garlic, onions, tomatoes, peppers, peas, etc., my last available space for okra was the same spot as the year before. I planted four varieties; they all grew beautifully, bloomed and began putting on pods but what followed was disaster. One by one, by one, leaves began to dry up; a few plants, heavily loaded with pods—fell over. Their roots, what was left, covered in tannish slime. “Oh yes!” though I, “It’s that danged okra/cotton root rot I forgot to address LAST YEAR.”

According to Texas A&M: Cotton root rot of okra, also known as Texas root rot, ozonium root rot or Phymatotrichum root rot, is a nasty fungal disease that attacks at least 2,000 species of broadleaf plants, including peanuts, alfalfa, cotton and okra. The fungus that causes Texas root rot in cotton and okra, also infects fruit, nut and shade trees, as well as many ornamental shrubs. The disease, which favors highly alkaline soils and hot summers, is mostly limited to the Southwestern United States. Symptoms of Texas root rot in okra generally appear during summer and early autumn when soil temperatures have reached at least 82 F. (28 C.). The leaves of a plant infected with cotton root rot of okra turn brown and dry, but usually don’t drop from the plant. When the wilted plant is pulled, the taproot will show severe rot and may be covered by a fuzzy, beige mold. If conditions are moist, circular spore mats consisting of a moldy, snow white growth may appear on the soil near dead plants. The mats, which range from 2 to 18 inches (5-46 cm.) in diameter, generally darken in color and dissipate in a few days. Initially, cotton root rot of okra generally affects only a few plants, but diseased areas grow in subsequent years because the pathogen is transmitted through the soil.

Okra/cotton root rot control is difficult because the fungus lives in the soil indefinitely. However, the following tips may help you manage the disease and keep it in check: Try planting oats, wheat or another cereal crop in fall, then plow the crop under before planting okra in spring. Grass crops may help delay infection by increasing the activity of microorganisms that inhibit growth of the fungus. Plant okra and other plants as early in the season as possible. By doing so, you may be able to harvest before the fungus becomes active. If you plant seeds, choose fast-maturing varieties. Practice crop rotation and avoid planting susceptible plants in the affected area for at least three or four years. Instead, plant non-susceptible plants such as corn and sorghum. You can also plant a barrier of disease-resistant plants around the infected area. Replace diseased ornamental plants with disease-resistant species. Plow the soil deeply and thoroughly immediately after harvest.

So, last fall I initiated my plan. Pulled and burned all okra plants then deep tilled the area. I planted that area, plus a 3 to 4-foot section all the way around with winter wheat. In a few days I will be tilling the wheat in; and I will NOT be planting okra there for a few years.

As always, happy gardening!