I made a sort of ad-hoc raised bed without edges for these plants. I raised a ridge about 30cm high, just like I have used for my potatoes, but this time I tamped the soil down very firmly with the back of a spade.
I placed the clumps about 8 inches apart, allowing the plants ample room to develop.
This is a photo from last year, to show you what I'm hoping for:
A clump of "Long Red Florence" onions (immature)
I was also able to plant the first half-dozen of the Shallots I rescued from the neglected plot late last year.
I put them at the end of the row of onions. If enough of the others sprout, I'll start a new row for them. As I've said previously, although I have 45 Shallots, I'll be happy if only 15 of them actually sprout! I just need to grow enough to be able to harvest a decent amount at the right time, and store them properly as my "seed-bank" for next year.