Bonnie Nowicki
It’s that time of year to plant new citrus trees and/or check if you are pruning, fertilizing, and watering adequately the citrus trees you have. As you enjoy your present harvest, maintaining the health of your citrus trees for future crops is crucial. As I stated in my citrus article back in March 2020, we must water deeply, penetrating below the root ball. Water every two to three days during the month after planting a new tree to establish a strong root system. Mature trees, four or more years old, require deep watering at least every 21 days as temperatures start to warm. Citrus should not be irrigated daily. Soil should be allowed to dry out to a depth of about six inches before the next irrigation. A noticeable sign of water stress occurs when the leaves turn a dull green and begin to curl from the edges inward.
Fertilizing newly planted citrus is unnecessary. Fertilizer is not required until the tree has been in the ground for two years. Once established, citrus trees are heavy nitrogen “feeders,” and supplemental fertilizer is required to ensure a good fruit crop and healthy tree. Do not overfertilize. You may burn the tree roots. Fertilize three times a year with one-third of the tree’s total annual nitrogen requirement applied in April-May, August-September, and January-February. Water before and after application. Please note, grapefruit will require 50% less fertilizer and lemons 10% more fertilizer than the recommended range of fertilizer to apply annually.
April is a great month to prune. Citrus wood is naturally strong and does not need to be regularly pruned. Branches are not likely to break under the stress of a large fruit load. Do remove sprouts by hand if small and use hand pruners to cautiously eliminate weak or dead limbs within the tree canopy to allow in more light. For larger branches, a sharp-bladed, curved tree saw is the ideal tool. If the trunk is newly exposed after pruning, it should be protected. One option is painting with white latex or other tree paint. Do not use an oil-based paint. Ongoing maintenance should include mulching around the tree base with several inches of mulch to help maintain soil moisture. Keep mulch away from the tree trunk.
I hope this review invigorates you to evaluate the rest of your yard. Happy Gardening!