A large basal bulb of walking onion (allium cepa proliferum) planted in fall around here will develop two or three strong shoots by spring. Left undivided, these will get to medium size, make a lot of topset bulbils and make medium size basal bulbs again by the next fall. A better way to manage them is to thin the shoots down to one by using them for green onions in the spring. Then you'll get a bigger main shoot, bigger topsets and a bigger basal bulb which can be used like a shallot in late summer and can be stored for a few months. Large topsets can be planted out in late summer to make small scallions by late fall or early spring. Small topsets in mid-summer can be pickled or used for cooking. I don't much experience with shallots, maybe someone else here is expert. As far as leeks, did you mean that you set out seedlings? I have never heard of 'sets' for leeks.

"Do you need to clip the tops of multiplying onions the same as regular onions?" I assume that you mean clipping the flower stalk... and that depends upon the onion. There are 3 main types of multiplier onions: - Walking onions, which form little to no ground bulb, are extremely winter hardy, and form small bulbs (topsets) at the end of their stalks, in place of flowers. - Perennial bulbing multipliers (such as shallots & potato onions) which divide at the base, and may form flower stalks. Both of these are Allium cepa, the same species as common bulbing onions. - Bunching onions, which are a different species (A. fistulosum) form no bulb, multiply at the base (to a greater or lesser degree, depending upon variety), and blossom in their second year. For any of these, clipping off the stalk as soon as it appears will stimulate better multiplication from the base, especially for the bunching onions. You might not want to clip the stalk for the walking onions, if you want the bulbils to increase the size of the patch, or to share with others. When I lived in San Diego, I was given a small nesting onion by a Hmong gardener, that multiplied very rapidly - splitting into up to 20 stalks. Looked like a bunching onion, but formed small bulbs. Left it behind when I moved, and haven't seen anything similar since.... wish I still had it here.

A few of mine have fallen over, but the leaves are still quite green. These are some of my red ones, the yellow onions are still standing tall, but have not seemed to bulb up yet. They were transplanted out on 4/15. Should I harvest the ones that have fallen over, or wait a bit longer until the leaves have turned brown?

Bon, They might be fine. With onions you just never know. My onions have no mulch on them this year and I don't intend to mulch until and if this infernal rain stops falling. I need for the soil to be able to dry up as much as possible in between rainstorms or in between rainy days. My usual heavy mulch strategy is on hold for some areas of the garden because the soil is far too wet as it is and I don't want for mulch to prevent it from achieving whatever little bit of drying out it can get between storms. I think one reason I have so many lovely volunteer plants this year is because the onion bed is not mulched. From that bed, I have dug up and moved hundreds of Laura Bush petunia seedlings, hundreds of moss rose seedlings, and dozens of catnip, basil, lemon basil, and chamomile seedlings. That onion bed is the gift that just keeps giving, and I didn't even use all the seedlings I dug up. A lot of them got pulled up and composted. It is relatively weed free and volunteer free now, but I weed it every single day that rain doesn't keep me out of the garden like it is doing today. I see good onion plant great, nice leaf development and happy plants, but even well-amended clay in raised beds can stay too wet if the rain falls several days a week like it has been falling lately. I'd have it mulched if I could, but that would almost guarantee the onions will rot. So, you know, even though you're drier than we are, the lack of mulch might not be hurting the onions as long as you keep them well-weeded. More so than most plants, onions cannot abide competition, so keeping them weed-free helps produce bigger, healthier onions. I have the pathways mulched to prevent soil splash and its related diseases. I have the tomato beds, the rows of sweet corn and the bean beds mulched to prevent soil splash and related diseases. I have the flowers mulched. The onions, though? If they are to survive, they must remain unmulched. Including the rain that has fallen on my garden today, we're approaching year-to-date rainfall of 14". It sounds good, no? Well, actually, no. That much rainfall this early hurts as much as or more than it helps. I'm not panicking yet, but after looking at my forecast for the next week, I am starting to think the back garden will not get planted because it is going to stay too muddy too late in the season. More and more this year's rainfall reminds me of 2007---when I still had tomato and pepper plants in containers in May and June because I couldn't put them in the ground.....and the plants in the ground were waterlogged and growth was stalled and some were dying. I ended up planting a lot in cat litter buckets and 5 gallon buckets that year because there was no other way to do it. Peppers are perfectly happy in cat litter buckets, but indeterminate tomato plants in 5 to 7 gallon pots require an incredible amount of water and fertilizer to stay happy even when the ground is too wet for them. 2007 was a horrible weather year. While 2014 started out kind of wonderful, the longer the rain falls, the more likely we see a repeat of 2007, or even 2004. While 2004 was great overall, the spring was far too wet with over a foot of rain in one month. I want rain and I appreciate getting it, but we're at the point that it is too much at once. I don't even remember what my onions did in 2004 or 2007 but I think they struggled and some bolted and some died. I always plant tons of them to allow for some to drown, burn up in drought, or be pounded into oblivion and our crazy weather is why I do that. I wish we could send all this excess moisture over to SW OK, particularly to the Altus and Duncan areas. Their lakes would love all the water runoff we are having here.