The legendary Chatham Island forget-me-not.
Many of the smaller islands off the coast of New Zealand have endemic species of what are known as megaherbs - gigantic forms of what are elsewhere normal smallish herbaceous perennials grown huge by the lack of native grazers and the year-round mild (but usually chilly) wet climate. Most of them are spectacular but difficult or unavailable in cultivation. Myosotidium is one of the few that is growable in the UK, and, in my experience at least, is easy and reliable.
Much has been written about growing this in the UK, including giving it a seaweed mulch each year (Myosotidium grows along the back of the beach in the wild). Generally it seems to be recommended only for the west coast in the UK where it gets a mild moist climate, or as a pot plant for the unheated greenhouse elsewhere.
The parent of my plants grows against the north facing wall of a house in East Sussex and has thrived despite everything the climate has thrown at it over the last few years (the first thing that happened after I planted it was getting covered in snow).
Being right up against the house it tends not to freeze in winter but being on the northern exposure means it never gets very hot either. The lack of sunshine doesn't seem to bother it at all. Not drying out is probably important and I suspect that unless you're very diligent with the watering and feeding, growing them in pots under glass is likely to be a struggle. If at all possible, get them in the ground in the open air.
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