Grapefruit Tree Fruit Production
I have a mature grapefruit tree that has produced bountiful pink grape fruit for the last three years. We moved into our house three years ago so I do not know the history of fruit production prior to that timeframe. After this years gleaning I noticed that there are very few new fruit for next years crop. I have not changed my watering or fertilization schedule. Is it common to have a tree \”take a year off\” after producing so much fruit or should I be concerned about the health of the tree? The tree looks very healthy with many full green leaves and new growth. I have friends who have two orange trees and a lemon tree and they are experiencing the same lack of new fruit.
Pima County Arizona
Citrus trees have some tendency to alternate bear with heavy crops every other year. Water, fertilizer and plant stress management can lessen the severity of you on year/off year cycling. A complete absence of flowering following a year of heavy production is likely because your fertilizer rates are too low. I would consult with University of Arizona citrus production fact sheets to identify the appropriate rates of fertilizer for your age tree. Cold temperatures, extremely hot temperatures, or dry soil during the budbreak and bloom period may also cause reduced fruit production. In my experience, most people are under-feeding their citrus tree, so that they need a year off to recover from a heavy crop. In Texas, a tree the size of the one in your photo should get approximately 6-8 pounds per tree of a 13-13-13 type fertllizer each year. That total amount is divided into 2-3 feedings--February, May and June. Use the 8 pound rate if there is a big crop, but drop back to 3-4 lbs if you have no crop. The message is feed more with abundant fruiting and feed less with absence of fruiting. In this way, alternate bearing severity should be less. However, consult with University of Arizona information, since your climate and soils are different than Texas.