Without doubt one of the most important jobs for any gardener is the suppression of weeds. They will, given half a chance, destroy our desired plants; out-competing them for light, space and nutrients. However they are also an inextricable part of our local ecology and we may achieve better overall results by aiming at their rigorous control rather than their total elimination. (To be fair though there are some such as bindweed and Equisetum which can never be tolerated at all or they will quickly take over entirely.)