Issue: August 1
Fruit trees do not usually bear good quality fruit the first year after planting
Q. I have 6 fruit trees in my yard. A Gravenstein Apple, Fuji Apple, two Blenheim Apricots, Santa Rosa Plum, Alberta Peach. I planted the trees last autumn. They survived the winter and fruited this spring. However, all of the fruit were small (less than 2" in diameter). Do you have any suggestions on what I need to do to increase the size and yield?
A. Dr. Ron Walser, NMSU Extension Urban Small Farm Specialist, and I discussed your question. He agreed with my first impression that it is not unusual for there to be such small fruit so soon after planting the trees. The general recommendation is to remove fruit the first year, but he said it is okay to leave one to see what is produced. Dr. Walser explained that the root system has not had time to develop to the size required to support good fruit production. Next year the fruit should be larger because the tree should have a better root system.
Fertilization and irrigation are also important, but do not apply nitrogen-containing fertilizer now. You can apply a nitrogen fertilizer after the tree becomes dormant in November (October in Northern New Mexico and at high elevations). Or, you can wait and fertilize next spring after new growth has been produced. A little fertilizer in the fall will assist the plant in developing a good root system since significant root development occurs in the autumn after cool air stops the growth of the top of the tree, but the residual warmth in the soil allows continued root growth. Dr. Walser pointed out that trees need only nitrogen fertilization under New Mexico soil conditions. The nitrogen can be applied as commercial fertilizer such as urea or ammonium sulfate, or as an organic nitrogen source such as compost or manure.
Dr. Walser also strongly recommended thinning of fruit even after the trees are established. He said that research has indicated that 30 leaves are needed for production of each good quality, full-sized peach and apricot. He said that apples may need fewer leaves per fruit. He said that this means spacing them at least 6 inches apart on the branch. When thinning peaches, you should leave fewer peaches at the ends of the branches (greater spacing between fruit) and more peaches (closer spacing) closer to the trunk, to reduce branch breakage. Dr. Walser often advises audiences that failure to thin fruit results in a pit with a little skin around it. To have quality fruit, thinning is essential.
For more gardening information, visit the NMSU Extension publications World Wide Web site at http://aces.nmsu.edu/pubs/_h.
Send your gardening questions to:
Yard and Garden, Attn: Dr. Curtis Smith
NMSU Agricultural Science Center
1036 Miller Rd. SW
Los Lunas, NM 87031
Curtis W. Smith, Ph.D., is an Extension Horticulture Specialist with New Mexico State University's Cooperative Extension Service. NMSU and the U.S. Department of Agriculture cooperating.