Young Plants Damaged by 40 degree nights

[Braeden]

Hey all-
I just planted in two of my beds yesterday and this morning my two basil plants, peppers, and tomatoes were looking rough. I live in Chicago and the nights right now are around 40-50 degrees Fahrenheit. I have two questions- Are my plants salvageable and what can I do to help them? Tonight I'll be covering them with cloth to help insulate.
Thanks.

[rainbowgardener]

Not looking good... Had they been well hardened off? We had a late frost (actual freeze) April 17 at my 90% last frost date (ten percent chance of having a frost that late) . I had a bunch of seedlings sitting out. But they were very hardened and had been through a bunch of cold (not freezing) nights. The tenderest ones, basils and impatiens died. The rest, including tomatoes and peppers, got wilted and the tops died. But they put out new shoots from lower down. I cut the dead parts off and they are recovering well, though set back from where they would have been without the frost.
So it wouldn't hurt to give yours a chance to recover. But do keep protecting them from cold.

[Braeden]

Not looking good... Had they been well hardened off? We had a late frost (actual freeze) April 17 at my 90% last frost date (ten percent chance of having a frost that late) . I had a bunch of seedlings sitting out. But they were very hardened and had been through a bunch of cold (not freezing) nights. The tenderest ones, basils and impatiens died. The rest, including tomatoes and peppers, got wilted and the tops died. But they put out new shoots from lower down. I cut the dead parts off and they are recovering well, though set back from where they would have been without the frost.
So it wouldn't hurt to give yours a chance to recover. But do keep protecting them from cold.

None of them really hardened- the stems feel fine and still alive. The leaves are what have died. Each of my basil plants had a little sprout coming up that's green and I'm hoping that's an indication they're still alive. It looks like from now on nights should be 50 and above which should be good! Thanks for the help.

[lakngulf]

They look like they took it tough. I planted tomatoes and squash too early this year. Plants made it but I am afraid they will be stunted.

[Braeden]

They look like they took it tough. I planted tomatoes and squash too early this year. Plants made it but I am afraid they will be stunted.

That's my main fear- even if they survive their growth will not be very good and not much fruit will be produced.

[SQWIB]

Basil is probably a goner.
I had the same issue with my peppers, eggplants and a cape gooseberry.
Lost a few and most are coming back.
Give it's few days and if the stems are still firm, you will probably see leaves starting lower on the stem or in the center of the plant.

[rainbowgardener]

"None of them really hardened- the stems feel fine and still alive."

By hardened off, I meant had they been through a process of acclimatizing to outdoors and to cold temperatures, temperature swings, etc.

If a plant is just coming out from inside and is tender, it will be much more damaged by a cold night than if it had a chance to get adapted first.

[applestar]

I was still thinking those looked like frost damage... a quick check of recent Chicago weather reports (I grabbed the first one which was accuweather)

Sun 4/22 62°/44°
Mon 4/23 64°/43°
Tue 4/24 64°/47°
Wed 4/25 53°/39°
Thu 4/26 66°/36°
Fri 4/27 55°/41°
Sat 4/28 51°/38°
Sun 4/29 57°/33°
Mon 4/30 77°/54°

That 33° looks suspiciously like it could have been accompanied by frost. Unless the last 77/54 is going to be the norm from here on out, the range of temps in the last couple of weeks seem too unstable. Tomatoes planted out with night time temp in the 40‘s will become stunted after 3-4 consecutive nights UNLESS followed each day by sunny upper 50’s to cloudy mid-60’s. Peppers can actually take the air temp as long as there’s no frost, but the ground temp needs to be higher than tomato’s and will get stunted due to roots getting too cold. Basil can’t take 40’s — needs 55 or higher.

BTW keeping at least one eggplant as an indicator with peppers works wonders — eggplants hold up their leaves when it’s too cold.

During the unstable highs and lows, the fierce wind will do in tender seedlings unless well hardened — I think the wind does more damage than the temperature. It’s also easy for the seedlings to get quickly dried out..

[SQWIB]

Tomatoes planted out with night time temp in the 40‘s will become stunted after 3-4 consecutive nights UNLESS followed each day by sunny upper 50’s to cloudy mid-60’s. Peppers can actually take the air temp as long as there’s no frost, but the ground temp needs to be higher than tomato’s and will get stunted due to roots getting too cold. Basil can’t take 40’s — needs 55 or higher.

BTW keeping at least one eggplant as an indicator with peppers works wonders — eggplants hold up their leaves when it’s too cold.

During the unstable highs and lows, the fierce wind will do in tender seedlings unless well hardened — I think the wind does more damage than the temperature. .

That's good to know, I had quite a few plants getting beat up but the daytime temps were higher. I really never gave the "Stunted" problem much thought, I figured if they survived they were fine and to be honest I have never noticed a difference in production from mothers day plantings to 40°F plantings.
Lost a few due to the combination of cold and wind though.

[Braeden]

I was still thinking those looked like frost damage... a quick check of recent Chicago weather reports (I grabbed the first one which was accuweather)

Sun 4/22 62°/44°
Mon 4/23 64°/43°
Tue 4/24 64°/47°
Wed 4/25 53°/39°
Thu 4/26 66°/36°
Fri 4/27 55°/41°
Sat 4/28 51°/38°
Sun 4/29 57°/33°
Mon 4/30 77°/54°

That 33° looks suspiciously like it could have been accompanied by frost. Unless the last 77/54 is going to be the norm from here on out, the range of temps in the last couple of weeks seem too unstable. Tomatoes planted out with night time temp in the 40‘s will become stunted after 3-4 consecutive nights UNLESS followed each day by sunny upper 50’s to cloudy mid-60’s. Peppers can actually take the air temp as long as there’s no frost, but the ground temp needs to be higher than tomato’s and will get stunted due to roots getting too cold. Basil can’t take 40’s — needs 55 or higher.

BTW keeping at least one eggplant as an indicator with peppers works wonders — eggplants hold up their leaves when it’s too cold.

During the unstable highs and lows, the fierce wind will do in tender seedlings unless well hardened — I think the wind does more damage than the temperature. It’s also easy for the seedlings to get quickly dried out..

One more day and they looked like they would have been fine Do you recommend I see how they recover before giving up and replanting? Also, will these plants mostly likely be stunted? Thanks!

[Braeden]

"None of them really hardened- the stems feel fine and still alive."

By hardened off, I meant had they been through a process of acclimatizing to outdoors and to cold temperatures, temperature swings, etc.

If a plant is just coming out from inside and is tender, it will be much more damaged by a cold night than if it had a chance to get adapted first.

Sorry for the misunderstanding- I’m new to this. They came from a greenhouse, so not really acclimated to outside.

[jal_ut]

40 degrees should not damage them. Nursery plants cannot be put right out in full sun as the bright sun burns the leaves. Start by putting nursery plants out about an hour before sunset, then bring them in and increase the out time each day for a week till they can take a full day of sunshine.

[jal_ut]

Quote: " I have two questions- Are my plants salvageable and what can I do to help them? "

Salvagable? Perhaps. Give them some time and see if they send out new leaves.
What can I do? Just keep them well watered.

[wisconsindead]

You shouldn't be keeping those plants outside overnight in April, let alone May for the most part. Next time, do more research about the plants to understand what they can tolerate. If I were you, I would go buy some plants from a nursery the weekend of the 19th, harden them off (research how to harden off plants) outside for that following week, and then plant them memorial day weekend. I am in Milwaukee, so our weather is pretty similar. You're still ahead of the pack for the most part, and you learned a lesson about what certain plants can tolerate. Experience is a good thing.

[kayjay]

Hi Braeden. I'm in the Toronto area, similar climate I'll assume. Basil, peppers and tomatoes are hot weather plants. My rule of thumb for them is that I wouldn't leave them outside overnight until the local stores are doing it. Y'know how they put up temporary fenced garden shops in the parking lot? At my local stores, the plants are not brought indoors overnight. Obviously, they don't want to destroy their inventory, so they won't set them up until the plants are hardy and they're confident in the weather.

There are cool season veggies that you can do this time of year. The cabbage family comes to mind (includes cauliflower, broccoli, kale, kohlrabi) as well as lettuce and spinach. I think most of them are better off planted directly from seed; I'm not sure how they'd transplant.

Good luck! Buy more seedlings when it's actually time to put them into the ground. Shame on the greenhouse if they told you it was a good idea to do so already.