Horseshoe Vetch Seeds hippocrepis comosa – grows best in light well-drained grassland and is suited to chalk and limestone soils on sites where there is plenty of sunlight. Plants host a wide range of insect life such as Bees, Butterflies and Caterpillars. Horseshoe Vetch is a very important plant for breeding butterflies, attracting a variety of species in the wild, such as the Adonis Blue, Chalkhill Blue, Silver-Studded Blue and Dingy Skipper, all of which will lay their eggs on the plant. This species is low growing, with yellow flowers, that appear from May to August resembling those of Bird’s foot trefoil. Horseshoe Vetch looks best growing with other chalk and limestone plants that flower in early to mid-summer such as Oxeye daisies, Greater Knapweed, Meadow Cranesbills and Small Scabious.