i dont know why a dormant plant would need winter watering ... especially if you healed them into non draining clay soil ... [you leave out some essential facts to figuring out what went wrong]

imo .. the base issue was winter in a pot ...

you should have healed them into mother earth .... without the pot ... in late fall ... if you had them then ... in essence.. you healed the pot in .. and held the plant in a plastic pot which i presume... may have been partially out of the soil ... just a variable you should have avoided ...

instead of just planting them.. you created a number of variable over which you had no ability to control ....

ken

speaking from having three raised carnivorous plant bogs.... rot can set in if the water stays stagnant and you get anaerobic decomposition in the media. In nature the water slowly flows through the bog... pulling air down into the media between rain events. Don't know if your plant likes the same but rot happens with the carnivorous plants too if you keep the water constantly filled at the same level and down allow air to the roots to some extent.

I should have.. from now on I think I will grow most plants in the ground instead of keeping them in pots. I wanted to keep them in pots so that when I move I can just easily carry it with me but I can always dig them up too I guess. I'm finally starting to realize the challenges associated with container growing. But I think it really depends on which plants they are. Obviously my hosta that my dad just threw in the pond with its roots completely submerged for 3 months is one tough plant.

I thought you were going to plant all your spreading plants in pots in the ground to keep them contained? Are you still going to do that?

Yea pot culture is hard mainly Due to watering fluctuations. I don’t think there would be issues if a bog/water plant is consistently moist/wet in a well draining mix. It’s plants that demand good drainage is the hardest even with the 5-1-1 mix. They don’t like to be overwatered, yet at the same time you can’t completely dry it out or else they look thin. My potted Japanese thyme for example. The ones in the ground are so dense and big but the ones in pots look so thin and small yet.

Heruga, I overwintered some pots in the garage when I didn't find places too plant them last year; a couple of rhododendrons, four asters, some natives. I gave them zero water in winter. They all came through fine with the exception of some extremely minor brown patches on the rhodies. They were watered when I put them in the garage and then completely forgotten. I was sure this spring I would have the opposite problem from you, but am very surprised and intrigued that they needed no additional watering.

I overwintered alot of bigger potted plants(mostly conifers) in my unattached garage as well and I watered it well before I officially put it in my garage. So the freeze thaw cycle would keep them from desiccation. I barely watered any of them but for this mints and my other small pots I heeled them in because the smaller the pot the more susceptible to freeze damage. And the spot happened to be in full sun, in a sheltered spot and the ground never really froze in that section. So the sun would dry them up often so I had to water occasionally even in winter. I would definitely wait until at least they are completely gone dry though.