Savable? Made a huge mistake and didn't overwinter

[power270lb]

So far in that NYC area up until yesterday it's been very mild for this time of year, consistently mid 50s. Temperature nosedived yesterday to 29 and is 19 as I right this. Had 8 dawn Redwoods, a big Chinese elm, 4 cuttings, a juniper and 3 Japanese weeping willows outside. Everything except the willows was in a large plastic bin to protect from wind damage and planned to add pine needles to protect roots etc. Didn't anticipate rain this past Sunday and was stuck at work. Completely forgot about the trees and for about 24 hours they sat in 4 inches of water and as I pulled out to move into garage they're almost frozen. Everything is currently in my garage that gets very little light. Are they ok there and because of this one day mistake did I just kill my plants? What can I do?

 

[Dav4]

24 hours of submerged roots is unlikely to cause any damage to any tree., and all of your trees are very cold hardy and will easily survive the typical cold a NYC winter offers. They'll do better outside then in the garage, I suspect, as it will be very difficult to keep that spot cool enough to maintain dormancy. I'd move them back outside once the severe cold has past then do some research- Lots of info on overwintering here.

 

[leatherback]

Don't worry. Plants do not die that easily, especially when dormant trees accept a lot more mall-treatment than people typically think.

 

[power270lb]

Don't worry. Plants do not die that easily, especially when dormant trees accept a lot more mall-treatment than people typically think.

@Dav4 yeah I overwintered for the first time last year, a juniper and it was my first bonsai. Different this time around because this time last year I had 2 trees, have 40+ now including cuttings. There's a spot under my pool deck that protects from rain so odds are I'm gonna move them there. Yous would still recommend covering pots up with pine needles etc yes? Out of curiosity how often do u water?

 

[leatherback]

Mine move to the ground if real frost (24F and below) is expected. They are sheltered from wind and sun and deal with winter like that. No watering here pretty much between ~October and March, as we have rain 80% of the time during that period

 

[Dav4]

@Dav4 yeah I overwintered for the first time last year, a juniper and it was my first bonsai. Different this time around because this time last year I had 2 trees, have 40+ now including cuttings. There's a spot under my pool deck that protects from rain so odds are I'm gonna move them there. Yous would still recommend covering pots up with pine needles etc yes? Out of curiosity how often do u water?

Mulching the pots in a protected area is good if you get protracted cold. When I lived in 7b GA, I hardly ever mulched my trees as getting them on the ground when the temps were dipping into the low 20's and teens was really all I needed to do, and a light covering of leaves were my go to for a week or two if the cold was going to stick around for more then a day or two. Watering is easy in the winter... I don't . Ma nature takes care of it for me, at least if the trees are outside. Here in MI, half my collection is frozen solid, covered in snow, and won't need to be watered until March or April. The other trees are in a cold room where the temps will hopefully stay in the 30's for the next 2 months... these trees get watered every 7-10 days.