Pruning is not always necessary. However, when pruning your tomatoes, remember these main points: sun protection, yield, disease implications.
Plants with two or more stems produce more tomatoes with better foliage protection from the sun than plants with one stem. However, tomatoes pruned to one leader will bear earlier but with less yield overall. Choose the stems you want to keep and pinch out the others as they develop. A dense leaf canopy may reduce the incidence of black mold and cracking but may increase the incidence of other fruit molds such as gray mold.
Severe pruning to one stem will reduce your total crop greatly and also is likely to increase the incidence of some diseases or disorders.
Before removing suckers or side shoots on a tomato plant, wait until two leaves develop and pinch above them. See the illustration above.
As for those yellow and then brown leaves at the bottom of the tomato plant, they can be removed without consequence. Be sure to check for presence of disease before tossing those tomato leaves into home compost.
If they are yellow because of disease, dispose in the garbage, please. And if you find disease on your tomatoes, be absolutely certain to disinfect everything that has touched the disease—garden gloves and hand pruners, especially.
Gardeners will find a complete list of pests and disorders of tomatoes here:
We’ll have more on tomato disorders in a couple of weeks.
Return often in the next few months and tell us how your garden grows. We love hearing from you!