Myosotodium hortensis is a legendary plant, from the beaches of Chatham Island (New Zealand and keep going a bit), where it is reported to be fertilised by rotting fish. (There is never any explanation of why the Chatham Island fish give up so easily.) The good news is that conventional fertilising arrangements are just as good. The bad news is that it is only reliably hardy in the milder parts of Britain. But the best news is that it is an outstanding plant, well worth every effort to preserve. (Simply keeping it in a large pot in a cold greenhouse is usually sufficient for us in eastern Scotland.) It rapidly produces a clump of sumptuous, glossy leaves, and above these come the huge heads of sky-blue, white-rimmed flowers, that give it its name of Chatham Island forget-me-not.