Athosanswered grow question 4 years ago With biobizz I've fed until harvest and have stopped 1 week before harvest. It tasted the same either way. In soil you should stop feeding at least a week before harvest, because that's how long it will take the plant to consume your last feeding, feeding that last week is a wast of nutes. Although I do not flush, I only give plain water with o runoff that last week.