Why do plants make suckers?

Suckers grow from root systems and while they can be useful for propagation, more often they’re a nuisance. For a plant, producing suckers is a good way to reproduce, by making a genetically identical copy of itself. ‘Adventitious’ buds on the roots grow into shoots, usually next to but sometimes quite a distance from the original plant, annoyingly often in a lawn, path or border.

Certain plants, particularly those with shallow root systems, sucker more readily, such as bay, cherry, hazel, lilac, plum, poplar, privet, robinia and stag’s-horn sumach. Grafted plants, for example roses, are also prone to producing suckers, which are easy to spot as they have different leaves from the main plant. Some growing conditions, such as a rocky sub-soil or a high water-table, can make suckering more likely, by encouraging the roots to come to the surface. Any gardening that damages roots may cause it too.

To control suckers, scrape away the soil and try to pull them off, so you remove the adventitious buds from which they grow. For larger areas of shallow roots with suckers, after removing them, you can try to discourage them by raising the soil level.

Emma Crawforth, Gardening Editor