QuestionsHow to growVegetable GrowingWeeds, Pests and DiseasesRoundup and veg growing 0 Vote Up Vote Down Ann-Marie O\’ Byrne asked 15 years ago I sprayed weeds in my veg patch with Roundup last week. When can I plant veg into that ground next? 1 Answers 0 Vote Up Vote Down Gerry Daly Staff answered 7 years ago You can sow or plant right away as Roundup only acts through green plant tissue and is rendered inactive in soil by the clay complex.