Thank you for using Ask an Expert for help finding plants that slugs and snails won’t eat.
First, these creatures are especially drawn to plants that are less healthy, so keeping all your plants in a strong, vigorous condition is a good start.
Over the years, I have collected information from various sources both scientific and personal on plants that slugs and snails tend to avoid. Of course, there is considerable variation in the desirability of all plant species, and a hungry snail will overcome its natural preferences in specific circumstances. But, here is a list of plants that my sources say are less attractive to slugs and snails.
Agapanthus, Ageratum, Alyssum, Anemone, Aquilegia (Columbine), Bamboo, Begonia, Campanula, Candytuft (evergreen), Coral bells, Cosmos, Crocosmia, Dianthus (Pinks, Carnations), Dicentra (Bleeding Hearts), Euphorbia, Ferns, Foxglove, Fuchsias, Geranium, Geum, Grasses, Hardy geraniums, Hellebores, Hemerocallis (Daylily), Hens and chicks, Hydrangeas, Iberis (Candytuft), Impatiens, Japanese anemones, Lady's mantle, Lavenders, Lobelia, Lupine, Nandina (heavenly bamboo), Nasturtium, Nemesia, Painted daisy (Pyrethrum), Pelargoniums, Penstemons, Peonies, Portulaca, Rudbeckia, Sedum, Solomon’s seal, Sweet woodruff, Thyme, Verbena, Wintergreen (teaberry), Yew, Zinnia.
Have a good gardening year,