Originally Posted by SatinSilver
Used coffee grinds are excellent for tomatoes, roses,etc.
Used coffee grounds are primarily rich in nitrogen, but don't have much phosphorus and potassium. So, if your soil has nitrogen deficiency, then yeah, use coffee grinds, but otherwise, it could be harmful for tomatoes. If you end up with too much nitrogen, this could contribute to BER.
Best fertilizer for tomatoes would be something with higher phosphorus content, for example 3-6-4.