Thinning Fruit on Grapefruit Trees
Question from Nelson:
I have a dwarf grapefruit tree and it has lots of flowers this year and now has clusters of tiny grapefruit. I know I need to separate them to have a healthy crop but don’t know how many to leave on each cluster…? Can you help me…?
Answer from Pat:
Due to their growth habit of producing their large fruits in bunches like grapes, grapefruit (Citrus paradisi) have the common name grapefruit—(Not “greatfruit”, as you have called this fruit, though that name would make sense!) Most grapefruit varieties set far too many small fruit in bunches, many more than branches can support to full size. Aim to thin out one half to two thirds of the small fruits, leaving the healthiest and largest, but don’t try to do the job all at once. The tree will drop off many on their own.
If you thin too many fruits too soon the tree might drop off many of the one’s you left hanging. ‘Melogold’, for example, does not hang on well to its fruit, so if you have that variety, don’t thin too much. If your tree is ‘Melogold’, thin out a quarter of the fruits now but wait until you see what the tree does on its own before taking off more. The point of thinning out the fruit on any grapefruit tree is to leave only as many as the tree can support without branches breaking. As the fruits grow you can take off more if you see you have left too many on a branch. You will get bigger and better grapefruit by thinning and you can space them out better on the branches.
I live in surprise,Az. and recently moved here. We have a grapefruit tree growing on the property which is about 10-12 ft. high. The fruit is pithy(dried up) and not edible. I removed all the fruit of the tree.I want to know what to do before it starts bearing fruit this coming summer(the date here is Feb, 2015. Should I thin it so it can get sunlight ? I recently saw one new fruit about an inch in diameter. The tree is heavy with foliage.
I hope you can advise me.
Thanks, philip
One possibility is that the fruit hung on the tree too long. (Grapefruit often cling to the tree without falling off.) In case that is the situation, I would remove all the fruit and fertilize it with an organic fertilizer recommended for citrus. Then wait for another crop to see if is good quality. (You do not mention if the tree is bearing flowers, but of course you will need flowers before you get fruit.) Leave the one small fruit in place to mature. A second possibility is that this tree grew from a grapefruit seed and is a dud, only worth keeping as an ornamental.
Before doing anything, however, I would take one of the fruits to the former University of Arizona Citrus Agricultural Research Center 1/3 mile south of Greeway Road on 188th Ave (Perryville Road) in Surprise Arizona. Ask an expert person in charge there and see if he or she gives you the same advice that I have given you or if they say something different. They are right there and can most likely advise you better than I could. You could also phone the Master Gardeners at the Arizona Extension in your area. Most likely there is a hotline nearby.