No fungicides have been evaluated for control of this disease on yuccas, although thiophanate methyl has been used to successfully treat other Fusarium diseases. Always check fungicide labels for legal uses on each plant and follow rates and intervals as noted on the label. Usually, constricted leaves have normal coloration. Low air temperatures account for most of the injury in open stock beds, while cold water draining through perforations in polyethylene film used for lining shade houses accounts for most of the injury to Sansevieria in Central Florida. Use solid cover structures which are properly heated.
Spots turn yellowish and finally brown as they mature.
They are generally elliptical and are scattered across the entire upper surface of older leaves. After about 4 months, black fruiting bodies form in sunken centers and are easily seen with the naked eye. Sometimes a yellow border forms around the spots. Since most yuccas are grown exposed to both overhead watering and rainfall, regular applications of fungicides are needed to prevent disease. Check labels of specific fungicides for yucca as well as rates and intervals of use.