One of the best things I have ever eaten is a fresh ripe Tropic Snow peach. It’s even better when it is picked off your own tree in your own garden and eaten on the spot (or having a neighbor share some of their fresh-picked fruit with you). On the other hand, there’s nothing worse than watching what appears to be another bumper crop fall to the ground over the last few weeks leaving the tree completely devoid of fruit this year. And it wasn’t only the peach tree dropping fruit. The same thing happened to two nectarine trees. I am now hearing from other folks that they aren’t seeing fruit set on their lemon trees. The plants are flowering but not setting fruit. There are several reasons causing premature fruit drop.
Fruit drop can be a normal process, up to as much as 80%. By dropping extra fruit, the tree can direct water and nutrients to the remaining fruit.
Fruit drop can also be caused by usually cold temperatures. If unusually cold or freezing temperatures occur just before the flower buds open, more fruit will drop. Temperature dipped (recorded at St. Simons airport) to 34°F on February 4. My pictures showed full blooms on February 15. The island temperatures then rose to 80°F on February 28 followed by 38°F on March 8.
Lack of pollinators
What I noticed most was the lack of honey bees on the flowers during those four weeks. I contacted the beekeepers at High Heel Farms, located in the exclusive community of Frederica and found out that they lost three hives over the winter. My trees are located within 2 miles of the farm. Bees can easily fly 3-5 miles in search of nectar and pollen. In the past, the trees have been buzzing with bee activity but the blooming date was a bit later and the temperatures consistently warmer. Sadly, the cold snaps and the loss of those hives may actually be the cause of the lack of pollination this year. It was suggested that I install a pollinator house which will attract bumble bees. Bumble bees are actually better pollinators. There is a pollinator house installed at High Heels Farm and it is attracting bumble bees. Bumble bees are cold-hardy foragers, active above 50°F and tolerant of cold, wet, windy conditions. Honeybees prefer temperatures above 60°F, and clear, sunny, calm weather.
High humidity and high heat
We had both of these issues when the trees were blooming this year. The island temperatures rose to 80°F on Feb. 28 before dropping back into the 30s in early March then back to 87°F on March 28. Our average temperatures for the two months should be 46°F to 63°F in February and 52°F to 69°F in March. Obviously, we don’t have control over these conditions.
Mother Nature is known to be fickle. Days of rain can be followed by long dry spells. Consistent watering of fruit trees can help overcome her unpredictable moods.
I am a strong advocate of yearly soil testing. It’s easy and results can be obtained rather quickly. Contact the local extension office to find out how or look it up online. Fruit tree fertilization requirements vary depending on the age of the tree. Publications that outline the procedure can be found at www.extension.uga.edu.
Pests and diseases
The most common pests are the plum curculio, a small native weevil that can cause injury all year long. Females lay eggs in the fruit and the hatching larvae and adults feed on the fruit. Infested fruit are often hard and misshapen. Fruits may fall prematurely in May. The peachtree borer and lesser peachtree borer are caterpillars that bore into the tree, causing major damage to the tree’s vascular system that transports water and nutrients throughout the tree. Although they don’t attack the fruit, infected limbs can die and in large infestations, the entire tree can be lost. Scale insects can attach to limbs and trunks, feeding on the bark, fruit and leaves. Heavy infestations kill the tree. Brown rot is a fungal disease that can infect flowers, shoot and fruit. It is very difficult to control without the use of fungicides. It occurs most severely in periods of high moisture. Again, check with a county extension agent if damage to your fruit is extensive.
When it comes to early fruit drop, it might just not be one of the above issues, but a combination of several. I have learned that abundant fruit yields should not be taken for granted. Although one can’t control Mother Nature, a vigilant program that carefully monitors insects and disease, watering and fertilization can help insure a good harvest. Also important is a conscientious steering away from the use of harmful pesticides and herbicides that kill off natural pollinators like the valuable honeybee. Hopefully, Mother Nature will cooperate and next year will be different.