Lesser Trefoil Seeds trifolium dubium – grows best in dry grassland on sites such as roadsides and waste ground where there is plenty of sunlight. In the wild Lesser Trefoil hosts the Common Blue as a breeding butterfly that will lay its eggs on the plant. This species is very similar to the Black Medick, from which it can be told apart by subtle differences in the leaves. Lesser Trefoil is a low growing clover with a small yellow flower that appears from June to August. Plants looks best growing with other short wildflowers that bloom in mid summer such as Lawn Daisies, Selfheal, Red Clover, White clover and Bird’s foot trefoil. An alternative names for Lesser Trefoil is Yellow Suckling Clover.