There is still time to spray citrus trees for the fall. Use horticultural oil, fish oil or neem oil for aphids, whitefly and spider mites. Follow label directions carefully. Citrus leaves that are yellowing around the edge and distorted may be lacking a trace element. Apply minor elements to your citrus trees either as a foliage spray or as a drench to the soil. Carefully mix sprays to apply only the recommended amount as stated on the product label. Minor elements will correct yellowing due to deficiencies of iron, magnesium and manganese, and will also supply copper, zinc, boron and other needed elements. Always refer to any local fertilizer ordinance when fertilizing. In Pinellas, for example, go to www.pinellascounty.org/PDF/Fertilizer-Ordinance-Brochure.pdf.
. Citrus fruit splitting and fruit drop may be a problem during the fall. This is a physiological problem that could be more pronounced just after a period of moisture stress followed by heavy rains. Splitting and drop will usually not be a serious problem if the trees are well cared for and furnished with adequate nutrition and irrigation.
Information from Carol Suggs and Theresa Badurek of the Pinellas County Extension Service and from the Hillsborough County Extension Gardening Almanac. Go to the extension websites at pinellascountyextension.org and hillsborough.extension.ufl.edu.