misc Temperature experiments with "spare" or cull plant's

Hi Guy's

Due to our short growing season both in light and temperatures a couple of years back I built myself a small simple light box WOW ! No more spindly leggy seedlings and I reckon it easily agave me a couple of month head start.

However the down side was a house full of big green bushy chillie plant's that I couldn't get outside for months due to our late random frost's also as usual I'd sown too many :rolleyes: and we all know how hard it is to cull our precious babies ! Last year after giving away as many spare chillie plant's as possible I was still left with a tray of plant's.........................

Not having the strength to chuck them in the compost heap :cry: I decided to use them for experiments in my unheated greenhouse, we get frosts often through May, June normally is safe. In past years when i finish work 1pm I'd put my trays out for some natural light in the greenhouse but bring them in each evening as they sun starts to fall a bit of a pain but what else to do.

However last year running out of space in my living room and even with a very tolerant wife I decided at the beginning "April" :eek: to put a tray of spare/cull plant's out in the greenhouse as an experiment a mixture of annuums and chinense sat them on the staging and put couple of layers of fleece over them ........good luck my little one's.

Next morning on the way to work at 04.30 am frost on the car I Peaked into the greenhouse.........1.6 oC ! Off to work fully expecting to find the contents of the tray keeled over dead as door nail ! What I returned from work however to my great surprise by 1.30 pm the sun was shining and it was it was up to double figures in centigrade and the plants looked fine which really took me back over the next week the lowest night temp in the greenhouse was 7oC the following week mostly 7oC to 12oC but the next week it crashed to 3 oC for most of the week but up again to mostly 7 oC.

After that I put my main chillie plant's out too with no ill effects and I noticed a much earlier crop than the year before as normally I wouldn't put my plant out till end of May and even then I was terrified of johnny frost creeping up on me and killing all my carefully nurtured plant's.

My temperature experiments with my cull plant's was a revelation even the chinense varieties can take much lower temperatures than I had thought ! I've even had them down at 0.8oC with no losses but that was with a light fleece over them but again in an unheated greenhouse !

Goes to show every day's a school day and I'm so glad I didn't put those cull plant's in the compost heap :halo:

That's very interesting and relatable. I am running into the same problem already and it's not even March... I need to keep hanging on for a month and perhaps I can start experimenting in my polytunnel like you did in your greenhouse.
That's great news for me. I normally don't start pepper seeds until beginning of April, but this year thought I'd take a punt.
Like you I have seedlings on windowsills and propagators on furniture, wherever there is light.
2 days of warm sunshine last week so put them in the greenhouse, brought them in at night.
Now with your experiments I think they might be able to go out for longer, thanks for that Englander.

Just remember - if all my seedlings peg it, it's your fault :lol:
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How come you started so early @Tinkerbelle? 😇

I have the six biggest plants on the windowsill in the kitchen. Needless to say a certain member of the household is not amused. (How many pepper plants do you really need, I heard him mumbling.)
How come you started so early @Tinkerbelle? 😇

I have the six biggest plants on the windowsill in the kitchen. Needless to say a certain member of the household is not amused. (How many pepper plants do you really need, I heard him mumbling.)
I have no idea how that happened, the seeds were calling to me :lol:

Have to say Mr Tink is starting to make noises about space and "how many more seed trays do you need in the house?"
Hi Guy's

After last year's temperature experiments and the resulting information gained into how resilient chillies really are !

I've taken it further this season the amount of light available in my greenhouse over my window sill is incredible ! And hugely beneficial to the growth of my chillies not to mention freeing up space on window sills and the like.

This season I put my spare/cull plant's out 20th February :shocked: obviously you "really " need to watch out for Johnny frost or all you hard work goes down the swanky !

Only difference to my unheated greenhouse is horticultural bubble wrap, but to be honest I've not really noticed a huge difference.................:think: for the expense......

Also if the forecast is for night lows of 1oC / 33.8oF I put a couple things layer of cheap thin horticultural fleece over them.

My plant's have been out inthe greenhouse here in Scotland constantly 24/7 for the last 14 day's, I've a max -min thermometer that records the lowest low and the highest high.

Here's the recorded temperatures from inside my unheated greenhouse over the last two weeks in "centigrade" for a quick conversion to Fahrenheit "double it and add 30"

20/02/23 = 9.3oC to 14.5 oC
21/02/23 = 9.8 to 15.4
22/02/23 = 6.9 to 22.5
23/02/23 = 0.8 to 15.5
24/02/23 = 6.4 to 12
25/02/23 = 4 to 12
26/0223 = -1.5 to 13
27/02/23 = 4.5 to 12
28/0223 = 4.5 to 12.5

01/03/23 = 2.7 to 14
02/03/23 = 5 to 12
03/03/23 = 5.4 to 14.1
04/03/23 = 1.5 to 17
05/03/23 = 2.2 to
06/03/23 = 3.7 to..........

No ill effects infact the opposite lots for fresh new growth !

There is a cold snap forecast from tonight for the next week ..........I might bring my babies in ? Well yes im not going to take any chances with my babies but I will probably leave out my spares and culls again to learn more.............

Hope you guy's in colder climates find this interesting and hopefully helpful