Certified GKH Gardening Expert
We normally do not advise pruning tomatoes, and the tomato fruit ripen with heat rather than sunlight. But if it is very dense, it could cause problems with airflow, which can invite disease in. If you decide to prune, use a very clean pair of shears and cut at the place where the branch you are trimming meets the stem. Allow it to air dry and do not water the foliage of the plant for a day after you prune.