it has been an issue for me as well. What do you do- save space on your tables and do bigger pots and then HOS or do several small pots of same variety and have HOS ready to go?
I use professional 2-3 in pots in trays and plastic covers which I have been reusing for several years- anything round is so hard to keep together and they do not sell square cups, do they? ;)

I used my bandsaw to cut 5 slits in the bottom of 25 2 liter containers and then cut them in half. I planted out some of the seeds that need stratification today. Larkspur and others. I also put my daylily seeds out. I had so many I used a lasagna pan for those. I may need another trip to the dollar store soon. Just in case.

Round cups are an issue, but I figure I can put them in larger containers to keep them from tumbling all over the place. And they won't need individual covers that way.

I hope I'm doing this right. I've spent a good deal on postage for all my seeds. Now I'm nervous about what I'm planning to winter sow and if it would be best to wait til spring. Last year I was extremely disappointed by my direct sowing. I got 5 plants out of 3 packs of each: Rudbeckia, coneflower, shasta daisy. I covered them with mulch after I sowed them. Yes, I know that was wrong.

Rudbeckia, coneflower and shasta daisy all ws very successfully for me in Zone 4 so expect that you do not need to worry about germination. Hope you have lots of space to plant all your sprouts.

Normally we wait until after the solstice to winter sow. I would like to hear the zone 7 people address this issue.

I'm zone 7 and I'll be waiting. Here's why. We still have too many opportunities for cold/warm/cold/warm/cold/warm spells between now and solstice. The seeds could be tricked into thinking it's time to sprout. I've seen too many fruit trees ruined this way, and lost 5 baby Japanese maples to such trickery last December. By solstice it should be cold for the duration.

Just my two cents,
seedmama

Not just in zone 7. Even with a winter storm a couple of weeks ago which gave us 2 feet of snow, the warmth from the gulf stream has returned and today I found lots of reseeded annuals sprouting in the gardens. The snow is all gone and since the ground hasn't frozen some seeds are just going for it.

In mid-January we are known to get a warm spell which wakes up a lot of things too, hence the reason I begin winter sowing in mid-February. Never really paid attention to our weather patterns until I started this in 2001/2002 and let me say it was a big learning curve kind of thing.

This is my first year to WS and like Token I am a little nervous about it. What I am doing is WS some of the seeds and keeping some back to plant in spring if I need to.

I've done some trees and shrubs. Mostly things that require stratification or have really tough coats. I plan to wait until New Years to sow my flowers. And spring to sow some annuals and tender perennials. I just want to be prepared since I have the time. And I'm nervous. LOL

Last year I went and bought one of those semi clear sterlite under the bed containers, burned holes in the bottom for drainage, the lid was solid, so I used 3mil plastic with slits and binder clipped to the sides.
I was able to get 80 of the plastic bathroom cups in there.

The issue I noticed was the different germination times in my attempt to be organized all-in-one container I needed to keep a close eye and pull some out before others were ready to plant out.

I still like using the gallon or 1/2 gallon milk containers and may use smaller sterlite shoe containers for the germination times about all the same.
I use those inside to start my impatiens and geraniums in a South facing window, works like a charm for those more tropical liking annuals. What is nice with those, for space saving, you can stack them ontop of each other, until you need to prick out and pot individually.
I could start ornamental grasses now and have them up in a weeek, but I don't feel like "mowing grass" inside.

I can't bother with Wsing now, because I am super cleaning the house, still canning some frozen foods, baking and holiday preparations.

Yep, winters here are up-n-down all the time it seems, or maybe I notice it more that I actually take the time to WRITE DOWN harse weather in a garden journal/calendar.

Heck we had enough warmth 3 weeks ago for roses to rebloom, my Lily of the Valley emerge, 17 degrees 2 weeks ago, yesterday 40. Yet, when I look at last years calendar, Feb it was -10 one week, the next week I had water lines freeze up. March 9th I was outside working in the veggie garden, with a note of "beutiful weather" the honey bees were out in full force.

What does HOS mean?

Hunk o seedlings. When you take out a plug from a container rather than individual plants.