What Makes Tomatoes Have Thick Skin?
There are typically three things that can cause tomatoes with tough skins. These things are:
Variety Watering Temperature
Tomato Variety Causes Tough Tomato Skin
The most common reason for thick tomato skins is simply variety. Some varieties of tomatoes just have thicker skins, and mostly for good reason. Roma tomatoes, plum tomatoes, and crack resistant tomato varieties will naturally have thick tomato skins. Roma tomatoes and plum tomatoes have thick skins partially because they have been bred that way. Roma tomatoes and plum tomatoes are often used for canning and drying. Thick or tough tomato skins help with these preserving processes. Thick tomato skins are easier to remove when canning and thick, tough tomato skins also hold together better when dried. Crack resistant tomato varieties have also been bred to have tough tomato skins. It is the thick skin on the tomatoes that makes them less likely to crack.
Under Watering Affects Tomato Skin Thickness
When tomato plants have too little water, they can develop tomato fruit with thick skins. This is a survival reaction on the tomato plant’s part. When the tomato plant has continually too little water, it will take steps to conserve the water it does get. One way a tomato plant conserves water is by growing tomatoes with thicker skins. The thick skin on the tomatoes, holds water in better. One way to avoid your tomato plants growing thick skinned tomatoes is to make sure that your garden’s getting enough water, particularly during times of prolonged drought. Watering tomatoes the right amount will help normally thin skinned tomatoes keep their thin skin.
High Temperatures Makes Tomatoes Have Thick Skin
High heat can also cause a tomato plant to have thick skin. In high heat, tomato fruit can be scalded by the sun. In order to prevent sunscald on the tomato fruit, the tomato plants will start to produce tomatoes with tougher skins. The tough tomato skins are less likely to burn in the intense sunlight. If you get a sudden heat wave and you want to avoid thick tomatoes skins, you can provide some shade for your tomato plants during the hottest times of the day to help keep them from starting to make thick skin tomato fruit. If you live in an area where high heat is just a fact of life, you may actually want to seek out thick skin tomato varieties. While the skins on your tomatoes may be thicker, your tomato plant will produce more fruit and you will be less likely to lose tomato fruit to sun damage.
