Varietal isolation

Varietal isolation involves separating different tomato varieties from one another to maintain the varietal purity of the seeds. The risk of cross-pollination is usually low, but it increases when insect activity is high and in varieties where the stigma protrudes beyond the anther cone. For small seed lots, the most reliable method is to cover unopened buds with a breathable bag until fruit set occurs and to label those fruits. The effectiveness of spatial isolation depends on the conditions, and hand pollination requires that the flower be protected beforehand.