There are around 180 species of toadflaxes, spread throughout Europe (with a couple of native species), Asia and into North Africa. Perennials or annuals, upright or low-growing. Very colourful flowers, in spikes, with each flower 2-lipped, containing a spur and a strange swelling which resembles a toads throat! The flowers as a whole arguably resemble shoals of exotic fish. They appreciate an open site, well-drained soils. Many will self-seed, including the hybrids, but they won't necessarily be the same as the parent, so some removal of seedlings maybe needed.
Toadflaxes, with bilaterally symmetrical, more-or-less closed, flowers are typical bee-pollinated species, those with larger flowers visited by bumblebees, the smaller ones by solitary bees. In addition butterflies and moths will visit those with more open flowers. The British native L. vulgaris is especially important given its typical autumnal flowering time, when there are few other natural nectar sources available. The leaves are the larval food plant for numerous moths: one of these, the toadflax brocade, is now found across south-eastern England after being apparently extinct in the mid-20th century. Its caterpillars are exceptionally attractive, yellow, black and white, and well worth sacrificing a few leaves for!