Square watermelons, portrait gourds, heart-shaped oranges, and Buddha pears are purposefully distorted fruits that can be a fun way to play with your plants. These distortions are kin to the method of tree training known as pleaching.
When it occurs without human intervention, however, fruit distortions warrant a closer look.
Affectionately known as ugly fruit, naturally occurring fruit distortions can be nothing more than cosmetic, or they can indicate the presence of pests, disease, nutrient deficiencies, or chemical misuse. It can also be caused by stress.
Fruit distortions caused by stress
Stressed out plants (and people) do not perform as well as they might otherwise. If you were a plant, those stresses might be drought, insect damage, extreme temperatures, herbivore feeding, mechanical injury, excessive salt, insufficient nitrogen, severe weed competition, or water stress. If you were a stressed-out member of the cabbage family, for example, you might start looking like a sun tan lotion advertisement from the ‘60s after you bronzed yourself a protective barrier. This is called buttoning. Stress-induced distortions also include stunting, misshapen flowers, and reduced leaf size. Mechanical injury or blockage of cucumbers and other cucurbits can cause crooking. Low temperatures during pollination causes uneven fruit development in strawberries. But what if it isn’t stress that is causing fruit distortion?
Fruit distortions caused by nutrient deficiency
Fruits grown in boron-deficient soil can also be distorted. Plant nutrients are critical to the proper development of fruit. If there isn’t enough boron, the fruit will be distorted. Of course, without a soil test from a reputable lab, you won’t know what’s in your soil. Unfortunately, those cute, over-the-counter soil tests are not [yet] accurate enough to be useful.
Insects that cause fruit distortion
Citrus bud mite feeding can cause some dramatic distortions, especially in citrus. While there really isn’t anything you can do to get rid of citrus bud mites, their feeding can create points of entry for other pests and diseases, so you will want to monitor infested trees.
Fungal disease and fruit distortion
Fungal diseases, such as apple scab, can also cause fruit distortion. Unfortunately, in this case, you won’t want to eat the fruit, as it will be mushy and rotten. One easy way to break the fungal disease triangle is to remove fallen leaves under infected trees and toss them in the trash. This reduces the chance of reinfection next spring.
Chemicals and distorted fruit
Since many herbicides are actually plant hormones (auxins) that force plants to grow so fast that they die, chemical misuse or overspray from a neighbor’s yard can cause fruit distortion. This is one time when, if in doubt, don’t eat it. If the suspected chemical is systemic, you won’t be able to wash it off.
Unless they are caused by chemicals or fungal disease, fruit distortions rarely impact taste or texture. These fruits are simply funny looking and should be enjoyed for their uniqueness.
You can grow a surprising amount of food in your own yard. Ask me how!