Why Does Basil Wilt?
Healthy basil plants require at least eight hours of sunlight every day, well-drained soil, and enough space to allow for plenty of air circulation. If you are meeting the plant’s basic needs and your basil plant keeps falling over anyway, there may be a more serious problem.
Fusarium Wilt
Basil plant droop that appears suddenly on young plants is often caused by fusarium wilt, a fungal disease that causes stunted growth and droopy, wilted, or yellow leaves. The first signs of trouble are decreased growth and leaves with a cupped appearance. Eventually, leaves may drop from the plant. Fusarium wilt is difficult to manage and can remain in the soil for 8 to 12 years. If you suspect your plant is infected with fusarium, you’ll probably have to start fresh with a new plant in a completely different location. Prevention is the best solution for fusarium wilt. Purchase healthy, disease-resistant plants. If you plant basil seeds, be sure the package indicates the seeds are fusarium tested.
Root Rot
Root rot is another common reason for droopy basil plants. Rot is a water-borne disease generally caused by improper irrigation or poorly drained soil. Let the soil dry slightly between watering, but don’t allow it to become bone dry. If the basil is in a pot, ensure the plant drains thoroughly after watering and never let the pot stand in water.
Leaf Spot
If your basil plant is starting to wilt and you notice brown, water-soaked spots on the leaves, it may be infected by various fungal diseases known as leaf spot. Remove affected leaves at the first sign of infection. To prevent the disease, water at the base of the plant and never use a sprinkler or spray attachment. If the disease isn’t serious, a fungal spray may help.
Pests
Aphids, spider mites, and other insects can suck the sap from basil, which may cause droopy leaves. Most sap-sucking insects are easily removed by spraying the leaves with an insecticidal soap spray. Use the spray strictly according to directions. Never spray the plant when the sun is directly on the foliage, or when temperatures are above 90 degrees F. (32 degrees C.).
