[Isolated]

pawn Код:

if(HasPlantWeed[playerid] == 1) return SendClientMessage(playerid, COLOR_GRAD2, "* You have already planted a weed !");

Change the '1' to the number you want.

Then change

pawn Код:

HasPlantWeed[playerid] = 1;

To

pawn Код:

HasPlantedWeed[playerid]++;