Some plants are such good value and so dependable that it’s difficult not to be evangelical about them. Perennial wallflowers (Erysimum) fall into that category. Some start to flower in February or March, and in mild years they may still be going at Christmas. Not bad, eh?
Technically, there are two types of erysimum, perennial and biennial. Experimentation has shown that if you leave biennial wallflowers (shorter, about 15cm, grown from seed and formerly called Cheiranthus, but now thankfully erysimums too) in the ground they often come back for a few years, forming small evergreen bushy plants. The reliably perennial, larger erysimums (about 40-60cm), which I’m focusing on, are longer flowering and more impactful. They do best in a sunny sheltered
