Landscape 911: First Aid for Ailing Foliage, Flowers and More

Like us, lawns and landscapes have their share of illnesses from time to time. Knowing the symptoms and how to treat them can make all the difference. Here are five diseases to be on the lookout for in your landscape.

  • Leaf spot causes circular spots on the leaves of plants, often causing leaves to drop. Pick off the diseased leaves and apply fungicides to protect uninfected leaves and new leaves.
  • Mildew is a gray powdered sugar-like coating that appears on leaves, new shoots and unopened blooms, most commonly on roses and crape myrtles. While it is chronic, mildew is not severely damaging and can be controlled with fungicides. (BTW, both leaf spot and mildew can be reduced by limiting irrigation on plant parts and by planting in the sun.)
  • Plants with blight wilt and turn brown and mushy. Annuals are the most common victim of the fungus. The most effective way to control blight is to remove the affected plants or prune twigs. When pruning, remember to sterilize the shears or you’ll spread the disease.
  • Rot is a soil borne fungal disease that attacks roots or plant tissue near the soil. In South Texas cotton root rot, which occurs mainly in alkaline clay soils, is common. (Take-all patch and brown patch in St. Augustine grass are examples of rot.)
  • The first symptom of mosaic is mottled leaves. There are no pesticides that combat viruses so the only solution is to pull out affected plants. Mosaic is a potential threat to St. Augustine grass lawns.

Regardless of the ailment, prevention is usually the best treatment. Avoid circumstances that encourage diseases to infect your landscape. Proper watering, mowing regularly and at the correct height (don’t mow too short), and careful planting practices are all key to maintaining a healthy landscape.

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Guest Author
Our Guest Authors are fantastic former SAWS employees, incredible interns and community leaders in the local landscaping world. They are all as passionate as we are about saving water with beautiful, diverse landscapes.
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