Planting temperatures

Gardening with Rabbits

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What daytime and nighttime temperatures do you plant your tomatoes and peppers outside? I need to harden mine off, but it has been too cold to even put them outside the greenhouse. Tonight is going to be 31 and then we have 30s and getting to 40s for lows for several weeks and highs will eventually get to 60s. I think it is going to be a long wait for planting these out in the garden and the peppers look so good. I am thinking of getting them hardened off and plant and cover with plastic and about cover them in straw.
 

flowerbug

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for us we plant out the warm weather crops towards the end of May. we're still getting frosts here so the ground isn't going to be warm enough. we got frosted last night again.
 

digitS'

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Here is the University of New Hampshire on tomatoes LINK:

"About ten days before transplanting, set plants outdoors for a few hours each day to acclimate them gradually to outdoor conditions. Start by setting plants in filtered light in a setting protected from strong breezes. Each day, prolong the period the tomato seedlings spend outdoors, exposing them gradually to direct sunlight and wind. ...
Bring plants indoors at night and on days when temperatures fall below 60°F."

They also advise against setting out in the garden before nighttime temperatures are above 60°.

Remember that in a semi-arid climate and at 2000+ feet elevation with mountains nearby, and at 48° N latitude -- transplanting out can be a time fraught with anxiety. That doesn't mean delay, delay, delay. Wait long enough and pot-bound plants suffer. It sounds like your peppers may need to be up-potted, for example.

If we follow the 60° guideline and skip back beyond our very unusual, record breaking 2021 to June 2020, we see that a nighttime low was not achieved until the 23rd. Then, the lows dropped as far as 48° before the end of the month! Wait until July to set out warm-season plants??

Overnight protection can help. Hopefully, chilly weather doesn't come with wind. Faced with extremes, my solution has been plants under a bucket held down with a rock. Running sprinklers during the coldest hours can mitigate the cold. All this because I sure don't think that waiting until mid-July is a reasonable choice.

Steve
 

meadow

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Straw also insulates against the heat of the sun. I have some straw mulch in several areas of my garden. The soil beneath it is COLD and WET. Not a great environment for tomatoes.

If you set up poly tunnels ahead of time, the soil will be nice and warm before planting. Cloches would work too, but a tunnel would be more effective for the conditions you've described (in my opinion).
 

flowerbug

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Straw also insulates against the heat of the sun. I have some straw mulch in several areas of my garden. The soil beneath it is COLD and WET. Not a great environment for tomatoes.

If you set up poly tunnels ahead of time, the soil will be nice and warm before planting. Cloches would work too, but a tunnel would be more effective for the conditions you've described (in my opinion).

i've often read suggestions to pull the mulch away from planting beds so that the sun can warm them up faster and then as summer gets on and you need the mulch to hold in the moisture you can put it back. i have so litle mulch here that i don't have that issue i just have to worry about late frosts.
 

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Here is the University of New Hampshire on tomatoes LINK:

"About ten days before transplanting, set plants outdoors for a few hours each day to acclimate them gradually to outdoor conditions. Start by setting plants in filtered light in a setting protected from strong breezes. Each day, prolong the period the tomato seedlings spend outdoors, exposing them gradually to direct sunlight and wind. ...
Bring plants indoors at night and on days when temperatures fall below 60°F."

They also advise against setting out in the garden before nighttime temperatures are above 60°.

Remember that in a semi-arid climate and at 2000+ feet elevation with mountains nearby, and at 48° N latitude -- transplanting out can be a time fraught with anxiety. That doesn't mean delay, delay, delay. Wait long enough and pot-bound plants suffer. It sounds like your peppers may need to be up-potted, for example.

If we follow the 60° guideline and skip back beyond our very unusual, record breaking 2021 to June 2020, we see that a nighttime low was not achieved until the 23rd. Then, the lows dropped as far as 48° before the end of the month! Wait until July to set out warm-season plants??

Overnight protection can help. Hopefully, chilly weather doesn't come with wind. Faced with extremes, my solution has been plants under a bucket held down with a rock. Running sprinklers during the coldest hours can mitigate the cold. All this because I sure don't think that waiting until mid-July is a reasonable choice.

Steve
I agree about not waiting until July. I just remember I did not get my peppers out early enough last year and they got root bound. It was just that I did not get to them and not really the weather. I do not have bigger pots to put them in. The tomatoes are in the biggest pots I have. I have had to put buckets over plants when planting in May. I guess this year I thought we would have a warmer May and I sure got fooled. I looked back and last May we had some 90 degree weather. We had a hot summer last year. It was the only year I ever put an AC in my kitchen and in June we had over 100 degrees and even 70s for lows and I do not ever remember that happening in Idaho. I am going to start hardening them off and bringing in at night and start planting peppers and cover them if I have to. The tomatoes are in big pots and they will be okay for awhile.
 

meadow

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i've often read suggestions to pull the mulch away from planting beds so that the sun can warm them up faster and then as summer gets on and you need the mulch to hold in the moisture you can put it back. i have so litle mulch here that i don't have that issue i just have to worry about late frosts.
I'd heard that too but this is the first year I've had a chance to experience it first-hand. What a mess! I removed it all from Garden #1 but left some on #2 just to suppress weeds. I was really surprised by just how cold and wet the ground was underneath the straw. I normally use dried grass clippings for mulch (we have LOTS of grass) and have not had that problem before.
 
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