While apricot trees generally have few pest or disease issues, they are notable for dropping immature fruit — that is apricot fruit not ripe falling from the tree. If you are lucky enough to have an apricot tree in your yard, you may wonder, “Why do my apricots stay green” and what can be done with apricots that do not ripen?
Why Do My Apricots Stay Green?
It can be difficult to determine why apricots aren’t ripening on the tree, but there’s a good chance the tree is experiencing some sort of stress. For example, stress can be caused by unseasonably hot, dry weather. In the absence of rainfall, apricots need a good soaking every 10 days. Stress can also be caused by lack of sunlight. Be sure the variety is suitable for your USDA growing zone.
Watch for signs of disease, including limb dieback, cankers, leaking sap or sparse, light-colored foliage.
Let’s talk a bit about growing an apricot tree in general. Apricots bloom early and are easily killed off by late frosts. Most apricots are self-fertile, but fruit set is much better when one or two other varieties are planted in close proximity. The trees will not start bearing fruit until the third or fourth growing season, at which point a dwarf variety should yield one to two bushels and a standard size tree about three to four bushels.
Apricots like to be in full sun and planted in most any soil provided it is well draining. Look for a dormant, bare root, year-old tree to plant in early spring, or in the fall if you live in a mild climate. Space standard size trees 25 feet apart and dwarf varieties about 8 to 12 feet apart.
Prune the apricot tree annually to encourage fruiting. When fruit is one inch in diameter, thin to three to four per cluster to promote greater fruit size and prevent overbearing, which will result in minimal fruit the following year.
What to Do With Unripe Apricots
Apricots ripen at different times on the tree. The fruit from Prunus armeniaca can be picked when it is fully colored even if it is still fairly hard. Apricots do ripen once removed from the tree if they are colored; apricots do not ripen when they are green. They will remain hard, green and flavorless. Fruits picked when colored and with a slight give to the skin can be ripened at room temp — not in the refrigerator — with some space between the fruit. Turn the fruit occasionally as it ripens. Of course, for the sweetest flavor, the fruit should be ripened on the tree if possible.
You can also place unripe fruit in a paper bag, which will trap the naturally emitted ethylene gas and hasten ripening. Adding an apple or banana will really accelerate this process. Be sure to keep the bag in a cool, dry place; a warm area will cause the fruit to spoil. Also, don’t place the fruit in plastic bags, as again, the apricots will likely rot. The resulting ripened fruit should be used quickly as it will only remain fresh for one to two days.
If you have apricots that are not ripening on the tree, you may have a later harvesting variety. Most apricot varietals ripen in early summer, a few late in the spring, but a couple of types are not ready for harvest until late in the summer. Also, fruit ripens earlier on well-thinned trees, so pruning may be a factor with unripe fruit.