Hardening off crisis

[jhook1997]

Here in zone 7 our weather is very unpredictable during the time when I need to be hardening off my "cold crops". I have cauliflower, Brussel sprouts and cabbage that I started several weeks ago. All are getting to the point of having several leaves but are still pretty wimpy. I started taking them out last week to harden off but only got to do it two days. It is now WINDY and too cold for that! I have a cold frame built and sort of a glass tunnel made from windows that I use when hardening and what I'm wondering is.....at what point/temp. can I just leave them outside in those? I can obviously protect them from the wind but what temp. can the cabbage and cauli withstand???

 

[MeggsyGardenGirl]

Here in zone 7 our weather is very unpredictable during the time when I need to be hardening off my "cold crops". I have cauliflower, Brussel sprouts and cabbage that I started several weeks ago. All are getting to the point of having several leaves but are still pretty wimpy. I started taking them out last week to harden off but only got to do it two days. It is now WINDY and too cold for that! I have a cold frame built and sort of a glass tunnel made from windows that I use when hardening and what I'm wondering is.....at what point/temp. can I just leave them outside in those? I can obviously protect them from the wind but what temp. can the cabbage and cauli withstand??? http://www.theeasygarden.com/forum/uploads/8794_image.jpg

I'm in zone 6/5 and I'm coming up to the same question, same variety of plants, same cold frame situation. What would everyone recommend the minimum low temp should be for cole/brassica crops? Also for onion seedlings. My daytime temps are creeping up to 70s/80s and now I'm venting my cold frames during the middle of the day. But night time temps are still pretty low - 33 degrees inside the cold frame last night and 29 degrees the night before. I put several gallons of water in milk or vinegar containers inside the cold frames to moderate the night temps, but doesn't seem help much. Any wisdom?

 

[lesa]

In my opinion, the hardening off process is the most difficult part of starting seeds. I am afraid the only answer I have found is to keep carrying the plants in and out- until you are really sick of it. Right about then, it is usually okay to leave them outside! jhook- those plants look like they are struggling a little. I wouldn't keep them outside in the cool temps yet... Happy Gardening!

 

[digitS']

I am really with Lesa on this one.

Leaving plants in containers out in difficult weather isn't much different than planting them out in the open garden. It is probably a little harder on them. Yes, you can find some protection for them and that may be as simple as covering them with a quilt or something. Or, moving them into a garage instead of back to indoor temperatures may be fine. They shouldn't be left in the dark for hours and hours, however.

You may want to just plant them out and surround them with newspaper, held down with rocks and held off the plants by a stake driven down near them. Leaving this "teepee" open a little at the top allows heat to escape and it can be completely closed at night.

I have exactly one location in my yard that is sorta ideal for hardening off. It is against the south wall of the house but protected both from midday sun by a deciduous tree about 12 feet away and from the prevailing wind by the steps from the deck. Plants only show up there for a few hours during the nicest part of the day - at first. During the final days of a couple weeks of hardening off, those plants will be right out in the middle of the yard - full sun and wind. Still, I won't leave them out at night unless I'm loading them in the truck to go out to the open garden the next morning. Just my little commitment to their care as seedlings.

Do I mess up sometimes and leave them out when they shouldn't be out there? Yes. Can I understand how folks handle hardening off who aren't home as much as I am? Only with difficulty :/. I think, a structure only open on the south side may be a way to go - still, too much sunlight would be a real problem if mid-day shading isn't provided.

Steve

 

[MeggsyGardenGirl]

Thanks for the reminder. Hardening off is such a drag, but you are right - it really can't be avoided. I've been putting my onion seedlings out in a protected spot for a few days, but only in the middle of the day and only for a couple hours. And good point about the mid day sun. One of my cold frames zoomed up to 87 degrees because I hadn't vented it earlier this week. Thankfully, nothing was growing in it at the time (whew!). I've had very good results in the past with my cold frames, but I've never tried to use them this early in the season. The low temps at night really scare me for any seedlings - hearty or not.

 

[Gardening with Rabbits]

I am really with Lesa on this one.

They shouldn't be left in the dark for hours and hours, however.

How many hours is too many?


Still, I won't leave them out at night unless I'm loading them in the truck to go out to the open garden the next morning.

What temperature is okay to leave them out at night?


Steve

 

[Gardening with Rabbits]

I've been putting my onion seedlings out in a protected spot for a few days, but only in the middle of the day and only for a couple hours.

I made a "greenhouse" and I have a feeling the thermometer is not that accurate. During the day it is 60s to 70s depending on how much I open it. When it gets dark I cover with quilts and the thermometer says 40 and in the morning it is 40. It is just .7 plastic. I think I probably have really stressed my onions, cabbage, broccoli, kale and mustard. They are alive, but really not growing. What temperature can onions handle?

 

[Gardening with Rabbits]

I wouldn't keep them outside in the cool temps yet... Happy Gardening!

I guess I am asking the same questions, what temperature can they take at night, but also what digits said about the dark, they would be better off in the greenhouse than outside in the dark. What was I thinking!!! For some reason I am pushing things a month early this year.

 

[canesisters]

Do I mess up sometimes and leave them out when they shouldn't be out there? Yes. Can I understand how folks handle hardening off who aren't home as much as I am? Only with difficulty :/. I think, a structure only open on the south side may be a way to go - still, too much sunlight would be a real problem if mid-day shading isn't provided.

Steve

It's COLD when I leave at 5am (30's) and cooling down fast when I get home at 6pm (40's) but has been up in the around 50-60 during the day.... Would just those couple of hours in the late afternoon do any good?
They're on a table, against the window in the spare room - so I've considered the option of opening the window so they'd have the chill but not as bad as without the warm room behind them... What do you think? Would that do ANY good at all? Or just be a huge waste of heat?
Can you harden off only on weekends?? Should I just give up till our night temps stop dropping so low? The corn is in a tote that weighs about 50lbs so toting that in and out and in and out and in and out is NOT going to be any fun at all. Everything else except the tomatoes should be getting a little sun/wind/air time...

 

[jhook1997]

Thanks for the replies everyone. Last year I did harden off by just running everything in and out but this year the temps seem to be really fluctuating. I started hardening off for a few days then had to stop due to severe cold. I also have waaaayyy more plants this year...um.....over 300 in my house right now!!

It's time for them to be outside and you all are right.....hardening off is the worst! I like the joy of starting my own seeds though and I have a greenhouse in the works.

So bottom line....what temp. Do y'all think these cole crops can be outside at night but protected ?