March 4, 1999
Question: I’m beginning to see new growth and some flower buds on my minneola tree. I’m not at all proud of the condition of the tree. Some remaining fruits are covered with sooty mold and the tree appears to be losing leaves. What would you suggest we do at this time in the way of tree care?
- Bruce Kilpatrick, North Fort Myers
Answer: Most citrus trees are easy to care for if given adequate water and fertilizer. However, once disease and insect pests become severe, it becomes important to take corrective steps at the prescribed time of year. March through April is one of two such times.
The fungal diseases of the season are primarily scab and alternaria brown spot. The insects of spring include aphids, whiteflies followed by citrus leafminer. Minneola and murcott are particularly susceptible to scab and alternaria brown spot. Of all the garden pesticides at ones disposal, only two are needed to return a citrus tree to its best health. Copper to control fungi and oil to control insects. These two chemicals can be mixed together at the recommended rates and apply several times to achieve control. Another important aspect of a tree’s good health are the applications of fertilizer and water. For mature trees, more than five years old, apply five pounds of 6-6-6, with micronutrients, now and again in May and September. A total of 15 pounds of fertilizer for the year. For a one to two year old tree, apply one to two pounds of 6-6-6 four to six times a year. During these dry times, irrigate twice weekly.
June and July will be the next window of opportunity to control another group of insect and disease pests of citrus trees. Summer disease and insect pests include greasy spot and citrus rust mites, respectively. However, for personal and neighborhood use, one should tolerate some imperfection of citrus fruits. The internal quality generally remains excellent. An adequately cared for tree usually requires no pesticide application.
- Stephen Brown is a horticulture agent with the Lee County Extension. To submit questions call the horticulture desk at 461- 7504 between 9 a.m. and 4 p.m. or via e-mail at shb@gnv.ifas.ufl.edu. Listen to the ‘Garden Show" at 8 a.m. on 1200-AM
WINK/WNOG.