temp swings

TightenUp · March 24, 2011

lights on vs lights off temp swings. right now i am holding steady at 78 degrees lights on. last night my lights off temp was 65. is this too cold or too much of a swing? whats ideal?

ssi912 · March 24, 2011

those temps are good. 78 is a wee high. shoot for between 70-75, unless your seedlings are getting to big, then keep the high temps between 60 and 70. the plants deal with temp. swings when growing in the garden. if you provide your seedlings with enough light, you should have strong transplants soon. take care.

TightenUp · March 24, 2011

thanks. i grown in a closet so i guess if i add some better exhaust i can bring the temp down.

the 78 degrees is not the temp of the room but the temp right under the cfls. the room stays nice and cool which is why i get the low temps with lights off. i actually have a space heater running just to keep that temp up to 65 with lights off.

**nctomatoman** · March 24, 2011

My young seedlings spend all day outside - talk about temp swings - two days in the low 80s...nights in the upper 30s tonight. Plus a good breeze. Makes 'em strong.

TightenUp · March 24, 2011

i guess i have less to worry about than i thought. what was your start date in NC?

**nctomatoman** · March 24, 2011

So I started my tomatoes on February 17 - most germinated by February 22. Moved them into the garage under lights on March 1 or so (wide temp variation - unheated garage - 70s to 40s). Eased them into sunlight by March 10 or so on nice days - started transplanting on March 21, and after a day or two in the garage resting, went outside into the elements on March 23.

TightenUp · March 24, 2011

awesome! good luck

Suze · March 25, 2011

In general, I think cooler temps (60's, or even a little cooler is fine) are ideal for growing seedlings because it tends to promote root growth and keep the plants stocky.

Warmer temps - 70's or above - will tend to favor top growth over root structure.

Edit/add - some temp swings are fine, and none of us live in a perfect world with exact control over the temps our seedlings might experience at all times. At least I don't! And as nctomatoman suggests, some changes/swings + some winds help them get tough. But do try to grow your seedlings a bit on the cool side if you can.

TightenUp · March 25, 2011

i got the daytime temp down to 73/74 by moving 1 of the 2 fans and leaving the door to the closet open. i didnt want to do this cause of the cats who roam throughout the house.

should i still drop to 65 during lights off or maybe go colder? i can prob get to the low 50s if i wanted to.

puttgirl · March 25, 2011

Good-after a couple of mild weeks it's gotten very cold (18 degrees tonight)! Got most tomatoes and peppers germinated and they were starting to stretch. Have them under lights today in my basement and it's pretty cold down there (in the fifties). I still might bring them upstairs tonight. I have a cat, too, that goes downstairs at night.

ireilly · March 25, 2011

As another perspective, I overwintered two pepper plants, and about a dozen tomato seedlings that were started late least year, just 'cause I wanted to see what would happen.

Everything kind of went dormant, and I only brought the plants in if it got below freezing. That worked, mostly, because I had one die from cold I think.

Now that the sun is out full-tilt, and the temps in the 70s at night and the 80s during the day, 3 tomato plants have died, a few more are struggling, and a few have taken off and are growing new branches and leaves. The peppers have aphids but are putting out new growth and flowers.

The cilantro and basil (not mentioned before) is flowering and I have coriander now.

All very interesting but I mentioned it all because they will survive more than you think. Once the heat and sun arrive they switch into high gear. I have at least 200 seedlings and plants in various stages of growth now, and now that the oak is trimmed back I have much more area I can grow on.

The peppers are the most temperature sensitive I think.

Waiting on the Kord pots I ordered now to arrive.

Happy growing!

organichris · March 25, 2011

I'm leaving most of my tomato seedlings outside on the porch all day now, unless it is dipping into the 30's, in which case they all come inside except the two I put in the earth.

My smaller ones stay indoors when temperatures are below 50 because I supposed that they may grow faster in warmer temperatures and under fluorescents. They've spent so much time outside already I think they're basically hardened off.

The pepper seedlings, which I purchased, are staying indoors unless the temperatures are above 60.

TightenUp · March 25, 2011

i wish i could bring them out! i got snow on the ground from last storm. i think a couple weeks before they get outside

March 24, 2011	#1
TightenUp Tomatovillian™ Join Date: Mar 2011 Location: Jersey Posts: 1,183	temp swings lights on vs lights off temp swings. right now i am holding steady at 78 degrees lights on. last night my lights off temp was 65. is this too cold or too much of a swing? whats ideal?

March 24, 2011	#4
nctomatoman Tomatoville® Moderator Join Date: Jan 2006 Location: Hendersonville, NC zone 7 Posts: 10,385	My young seedlings spend all day outside - talk about temp swings - two days in the low 80s...nights in the upper 30s tonight. Plus a good breeze. Makes 'em strong. __________________ Craig

March 24, 2011	#6
nctomatoman Tomatoville® Moderator Join Date: Jan 2006 Location: Hendersonville, NC zone 7 Posts: 10,385	So I started my tomatoes on February 17 - most germinated by February 22. Moved them into the garage under lights on March 1 or so (wide temp variation - unheated garage - 70s to 40s). Eased them into sunlight by March 10 or so on nice days - started transplanting on March 21, and after a day or two in the garage resting, went outside into the elements on March 23. __________________ Craig

March 25, 2011	#10
puttgirl Tomatovillian™ Join Date: Aug 2008 Location: SW PA Posts: 281	Good-after a couple of mild weeks it's gotten very cold (18 degrees tonight)! Got most tomatoes and peppers germinated and they were starting to stretch. Have them under lights today in my basement and it's pretty cold down there (in the fifties). I still might bring them upstairs tonight. I have a cat, too, that goes downstairs at night. Last edited by puttgirl; March 25, 2011 at 08:53 PM.

March 24, 2011	#2
ssi912 Tomatovillian™ Join Date: May 2009 Location: St. Simons Island, Ga. Posts: 83	those temps are good. 78 is a wee high. shoot for between 70-75, unless your seedlings are getting to big, then keep the high temps between 60 and 70. the plants deal with temp. swings when growing in the garden. if you provide your seedlings with enough light, you should have strong transplants soon. take care.

March 25, 2011	#8
Suze Tomatovillian™ Join Date: Jan 2006 Location: Texas Posts: 3,027	In general, I think cooler temps (60's, or even a little cooler is fine) are ideal for growing seedlings because it tends to promote root growth and keep the plants stocky. Warmer temps - 70's or above - will tend to favor top growth over root structure. Edit/add - some temp swings are fine, and none of us live in a perfect world with exact control over the temps our seedlings might experience at all times. At least I don't! And as nctomatoman suggests, some changes/swings + some winds help them get tough. But do try to grow your seedlings a bit on the cool side if you can.

March 25, 2011	#11
ireilly Tomatovillian™ Join Date: May 2010 Location: Dallas Posts: 344	As another perspective, I overwintered two pepper plants, and about a dozen tomato seedlings that were started late least year, just 'cause I wanted to see what would happen. Everything kind of went dormant, and I only brought the plants in if it got below freezing. That worked, mostly, because I had one die from cold I think. Now that the sun is out full-tilt, and the temps in the 70s at night and the 80s during the day, 3 tomato plants have died, a few more are struggling, and a few have taken off and are growing new branches and leaves. The peppers have aphids but are putting out new growth and flowers. The cilantro and basil (not mentioned before) is flowering and I have coriander now. All very interesting but I mentioned it all because they will survive more than you think. Once the heat and sun arrive they switch into high gear. I have at least 200 seedlings and plants in various stages of growth now, and now that the oak is trimmed back I have much more area I can grow on. The peppers are the most temperature sensitive I think. Waiting on the Kord pots I ordered now to arrive. Happy growing!

March 25, 2011	#12
organichris Tomatovillian™ Join Date: Jun 2007 Location: Tulsa, OK Posts: 630	I'm leaving most of my tomato seedlings outside on the porch all day now, unless it is dipping into the 30's, in which case they all come inside except the two I put in the earth. My smaller ones stay indoors when temperatures are below 50 because I supposed that they may grow faster in warmer temperatures and under fluorescents. They've spent so much time outside already I think they're basically hardened off. The pepper seedlings, which I purchased, are staying indoors unless the temperatures are above 60.