Following a forecast for heavy rain, the charity has expressed concern that the bugs will become more active and be especially hungry. The RHS said Hosta plants will be particularly vulnerable.
The RHS recommended growers who prefer more natural ways of control to water new batches of nematodes (Nemaslug) as any previously applied will have died in the dry soil.
Nematodes are microscopic worm-like creatures that enter the bodies of slugs and infect them with a fatal bacterial disease.
The traditional methods of barriers such as copper tapes around plant pots and mineral granules and egg shells sprinkled around plants are options but for those experiencing a large infestation of pests, proprietary slug pellets containing ferric phosphate or metaldehyde can be used.
See www.rhs.org.uk for more advice on how to deal with slugs and snails.