April 23, 2016

1 - Late frosts and weather conditions reducing the availability of pollinator insects are common reasons for failure of fruit trees to produce fruit in New Mexico.

Q.

My apricot, apple, and pear trees bloomed beautifully early this spring, but now I cannot find any fruit on the trees. Did we have enough frost to kill the fruit? Or is there another reason there is no fruit?

A.

We had warm weather in February, then cold weather in March, they warmth in April and then it has turned cold again. Some of the cold weather may have been sufficient to kill the blossoms on your fruit tree. This depends on the location of your trees in the state (you did not identify your location). It also depends on the microclimatic location of the trees on your own property. Apricot trees on the north side of a house often bloom later than trees in a warmer location, such as the south side of the house. Often a slight delay in flowering can be the difference in a fruit production or loss. However, I have seen situations where an earlier flowering tree was able to form fruit while later blooming trees failed to produce a fruit crop. This was due to the fact that the earlier blooming tree had produced enough leaves to protect the fruit when cold weather returned. The leaves hold in heat from warm sunny days and protect the fruit from freezing temperatures at night. This requires that the freezing temperatures be brief and sufficient warmth absorbed by the soil under the tree.

In my garden the timing of the freezes this year was just right to kill most of my apple and pear blossoms. However in searching through the apple tree, I did find a few fruit that had survived. The apple usually flowers late enough to escape most of the damage, but they did not escape this year. My apricot trees were still blooming after some of the freezing weather, so perhaps there will be some apricots. My plums had finished blooming and produced a good leaf crop, but the cold was sufficient to kill most of the fruit forming on the plum tree. I will have to wait until any fruit that escaped the freezing weather enlarges enough to be easily seen. This may be the case for you as well. Some years there are some surprising survivors.

Another consideration for New Mexico gardeners is the availability of pollinators when the fruit trees are flowering. Some years the cold weather and precipitation may reduce the numbers of insects that pollinate the flowers. However, I noticed several kinds of insects working the flowers in my trees. I hope you also had the pollinators out and working the fruit trees in your areas as well. In my garden I saw honey bees, a few bumble bees, and some hover flies visiting my fruit trees. In years when there are few pollinator insects, the flowers will appear on the fruit trees, but they will not produce fruit.

For now, just care for your trees so that any fruit that was formed can develop. You may be able to see any survivor fruits in a few weeks. If no fruit forms, the good news is that the tree can build its strength for a good crop next year.


Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: desertblooms@nmsu.edu, office: 505-865-7340, ext. 113.

Links:

For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms.

Send gardening questions to Southwest Yard and Garden - Attn: Dr. Marisa Thompson at desertblooms@nmsu.edu, or at the Desert Blooms Facebook page.

Please copy your County Extension Agent and indicate your county of residence when you submit your question!