Posted: 29/05/2017 at 10:35
Planting them deeply is really necessary.
1. Generally the bigger the Allium the less likely they are to multiply quickly, though in fertile soil they will. The smaller kinds multiply faster than you can weed them out.
I let the big one seed around and they flower in a few years.
2. They are winter growers and once the flowers appear the leaves have done their jobs and begin to die back. The people who show them remove the leaves and just leave the flower stalk. Once that has finished,ie gone to seed, you may dig up the bulbs .
3. Sorry cannot really help on this I have never dug any of ours up and stored them. If the bulbs are rootless then yes, you should be able to store them. Cool and dry would be best. They do need planting in about September though.