I'm not sure I understand the concern, you'd want some nitrogen when growing tomatoes, and coffee grounds don't contain a great deal in any case. It's also slow release, being in the form of organic nitrogen. In the earlier thread on coffee grounds the concern was that fresh grounds may "tie up" nitrogen and therefore deprive the plants. If the grounds are mixed with the other material and it's all composted (given the weather we are having in the north, cold temperatures might slow that down though) I don't think the tomatoes would be adversely affected either way. Did I understand the question correctly?
