When I grow tomatoes from my own seeds, I usually buy fresh seeds of the variety in question every few years. On the one hand, there may be some cross-pollination, and on the other hand, other genetic changes may occur over time.
A good example is the manure bench here with Bloody Butcher, where on one side there are 2 plants from seeds I took last year, and on the other side plants from newly purchased seeds from this year. The difference is quite striking - the plants on the right are clearly weaker, and I have already had to remove some yellow / brown slightly moldy leaves. So it must be clear to everyone that the wise gardener buys new seeds from time to time.
The problem is simply that the somewhat meager plants on the right ARE from the new seeds. Growing a vegetable garden is a source of constant wonder ??
Written by Peter Norris