Have tried different methods over the years, of digging them up,drying them trying to keep them, none, worked. Went to see a elderly chap, guess well into his 80s who has a house about a mile from me, because his are amazing, he said he has not lifted them in the 7 years they have been in his front garden, he just cuts the tops down to about 6 inches and thats it. I bought lots last year, had a fantstic display, and my 3 greenhouses were full of overwintering bananas,citrus,pelargoniums, etc etc, so I mulched them with about 5 inches of home made compost, and added wicker hanging baskets over the top, I dont know how they are fairing. The Monty" when they have been blackened by frost, we didnt have any frost!! Last year I read in my gardening weekly, plant the tubers in compost, water lightly, cover the pot completely to exlucde light for 10 days, put mine under the greenhouse bench and was amazed by the speed of growth, have done the same this year with them, (bought cheaply Pound Store, and Wilko) also grew some from seed last year T & M, freebies from same gardening mag, couldnt believe how big the tubers were after just a few weeks.
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