You're a bit colder up there in zones 5/6, while I'm here in 7a/b along the Jersey shore, and I'll have to look into this and will be interested in other posts, but will dive on in ...

First of all, I'm wondering why your daylilies are in pots rather than in the ground. I'm far from an expert on them, but have several varieties and have found them to be quite tough and adaptable.

I do think it likely that it wasn't extreme cold but alternate freezing/thawing, which is more likely to occur in a pot than in the ground, that was responsible for your daylily losses.

If you must keep them in pots (perhaps you use them in planters in the summer?), then perhaps you could sink those pots into the ground in winter (just be sure they have adequete - but not too much - water). Since the roots are frequently sold in a rather dry, dormant state, I would imagine another means of overwintering would be to treat them like the tubers/rhizomes/corms of tender plants like dahlia or gladiolus: allow to go dormant and store in a cool but above-freezing location like a cold cellar or attached garage.

Interesting idea to convert the kennel, but I'm afraid you'd find that would heat up considerably on sunny days, then cool down rapidly at night ... making for another freeze/thaw problem.

Diane

Thanks Diane. The reason they are not in the ground is because I need to convine my DH that I need another daylily bed.

I thought if I could keep them in the kennel and use some plastic around it, especially the west side, it would protect them from the cold winter winds. I have an unheated basement I could keep them in but I don't know if it would be cold enough, especially for the dormants. At present I have many on the 'floor' of a huge bark pile. I took the bark that is still available and have put it between the rows, and up the sides of the 3 gal. pots. Maybe this is still my best solution. I asked this question on the Daylily Forum last year, and I got similar answers as yours. The first suggestion was not to buy more daylilies until I get another bed ready for them, but I couldn't pass up on the lavenders.
Jane

I've overwintered many different varieties of hemocallus in pots, but never less than 5 gallon size, set on the ground where they would get moisture, just as they would if planted, although sinking the pots really would be better, and may be a lot easier than trying to make a shed out of that kennel.

I'm in zone 6 and we get some bitter cold days and nights here in winter. I would sink them in the ground in a sunny spot. I have yet to lose a daylily over the winter. Daylilies are very hardy. My Aunt grew them upstate NY in Zone 4 or 5. Leaving the pots to freeze and thaw is not a good idea.

I dug my own flower beds. Maybe you need to get the shovel out and start digging. :o)

Whoa ... put away that shovel and use the lasagne method (also known as sheet composting) and you won't have to dig until you're ready to plant. You've probably heard about it, spread 6+ layers of newspaper right on top of the ground/grass where you want the bed, then compost, then mulch, repeat the pattern, watering each layer as you go, 'til you run out of ingredients. Then sit back and let your soil organisms do the work. If you do it now, by spring you'll have soft, rich soil that will make planting a breeze. I tried it on our poor, compaction-prone silty sand and in just a few months in early spring that bed was transformed.

Of course, that would still leave you with having to overwinter these daylilies in their pots just one more time.

One thing I've found in sinking the pots is that the soil in the pots often dries out more quickly than the surrounding soil.

One last thought: Do you have a vegetable garden? After the veggies have been pulled out, I find it makes a great holding bed for those irresistable end-of-season bargains on perennials.

Thanks everyone for your suggestions.

It is not the labor involved in making a new bed because I did that last spring. I bought two loads of top soil, and a load of mushroom mulch and mixed it with the soil I had tilled from what was previously lawn. It measures approx. 25' x 80'. I did this by myself with the exception of a small mound of dirt my husband moved for me when the guy missed his mark when he started to dump the top soil. I did have a vegetable garden but that has now been incorporated into the large bed. We will possibly need new drains for our septic system so I do not want to add any new beds until we are sure of their location, etc. so the pots must remain.

Jane