I tried that by planting one up in a pot and burying a few in the garden. After about 2 years, the potted one that I had grown bored with and stood in the garden, showed signs of life then promptly died. The others, a few years later, I'd forgotten about till I read your letter and I went and checked and I'm not sure it's them, but there are a couple of stems I've not seen before. I did know they were very slow growers, but I hadn't realised how slow! I think that's why they're so expensive at the garden centres.