Hardening off

Growin to Harvesting

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ChilliJez
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Hardening off

Post by ChilliJez »

We're all looking for the soonest opportunity to get plants out in some way or another, greenhouse or outside.

I'd just mention to people who might not know about aclimatising their plants to their new environment. It's a very good idea to introduce your plants gradually so they don't suffer a shock. Put them in their new place for a few hours each day, when it's most favourable initially, and gradually increase the time each day, over about a week, It's known a hardening off and it will avoid your plants just stopping altogether for 2 or 3 weeks.

Ask if you need to know more. Just a reminder/heads up. :P .

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Mustafa Chilli
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Re: Hardening off

Post by Mustafa Chilli »

Does the same apply to plants that have overwintered?

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Chilli Keith
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Re: Hardening off

Post by Chilli Keith »

Thanks Jeremy. I hope ours are pretty hardened off already, although I will gradually open windows and door in the greenhouse before they move to the tunnel. Saying that, the tunnel is considerably warmer than the greenhouse at times (probably the AstroTurf!).

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Re: Hardening off

Post by Leif »

A coldframe is ideal for hardening off. It is also useful for germinating vegetable seedlings early, for raising plants such as lettuce and for warming soil ready for planting.
Mustafa Chilli wrote:Does the same apply to plants that have overwintered?
Yes, any new growth will be soft, and needs gradual exposure to outdoor conditions to harden the tissues.

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Mustafa Chilli
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Re: Hardening off

Post by Mustafa Chilli »

Thanks, Leif. I had an idea that it would be that case, and another part of me thought that the plants may have grown a set of balls, and wouldn't be so delicate.

Only two of my plants survived over winter, and to be honest, the plants grown this year look better. (more growth etc.)

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Re: Hardening off

Post by Slyboy »

It's funny that new plants look better than over wintered but wait until a bit of sunshine kicks in and you will find the overwintered produce pods earlier and in much greater quantities than new ones. I was a bit surprised how much an overwintered plant can do.

For example last year my overwintered 7pot produced about 4 times as much as a new 7pot. I think it makes more of a difference on a Chinense type though.

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Mustafa Chilli
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Re: Hardening off

Post by Mustafa Chilli »

I hope so Slyboy. Some of my new plants have had unopened flowers since December. They kept going yellow, and dropping off. Only the last couple of weeks that they have actually opened and produced pollen. The overwintered ones are far from that stage.

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Re: Hardening off

Post by chilliman64 »

this is a good topic, please all try to keep on topic as much as possible and we might be able to make a sticky/FAQ out of it

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Re: Hardening off

Post by Leif »

My overwintered Rocoto is two feet tall and covered in luxuriant growth. My seedlings are 8" tall max, with one main stem and a few tiny side stems. In the past I have had pods in late May from an overwintered Orange Hab, and a second flush in autumn, so basically at least twice as many pods, and much much earlier.

I think overwintered plants need hardening, the reason being that the new growth will be soft and easily damaged by cold and wind.

Incidentally I saw a recent nighttime temperature plot for a greenhouse. 16C during the day fell to 4C just before sunrise, with a gradual fall during the night, and a rapid climb at sunrise. 4C could damage C. chinense. Not sure about others, mature C. pubescens plants can survive frosts, seedlings might not.

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Re: Hardening off

Post by dennish »

I've been transferring my Baccatum and Pubescens plants to the GH each day and back in at night if the temps dip <5C and leaving them out if 5C or above. So far so good, haven't noticed any slowdown. WIll be potting them up to bigger pots very soon, when they will stay out in the GH regardless, hopefully this period of gradual adjustment will stand them in good stead... Then it's the same process for the Chinenses as hopefully night temps improve towards the start of May...

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Re: Hardening off

Post by Squarenips »

I've had some of my plants on windowsills for a month or so now and the rest I've been taking outside during the sunny days and bringing them in at night.

I've potted up my quadgrows with compost mix, as I was fooled by the recent sunshine. They're still devoid of chilli plants though as I saw a recent weather forecast indicating temperatures dipping into the minuses overnight, within the next couple of weeks :roll:

Start of May is where this particular forecast is hinting at overnight temperatures of 10 degrees plus...

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Mustafa Chilli
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Re: Hardening off

Post by Mustafa Chilli »

I have some in the poly 24/7. Some are on windowsills, some are in the vitopod. All the ones with flowers on are brought in each night and fill up every space in the kitchen, including the sink. It is certainly keeping me fit with all this walking back and forth.

The lowest temps that the BBC say will be for my area are 5 degrees, but that seems to be around 5am - and it starts to get warmer right after, so no problem... fingers crossed.

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Re: Hardening off

Post by GreyAreaUK »

All my annuums are now in the greenhouse fulltime, in a please-don't-die capacity :-)

I'm still bringing the habs in overnight if the temp looks to be dipping under 7C or so. Can't quite make up my mind what the 'safe' temperature would be.

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Re: Hardening off

Post by Leif »

I am risking most of mine in the coldframe, maybe a bit low at night, but the coldframe prevents wind chill and warms the ground so,it acts as a heater at night. Thus far ones in the coldframe are growing a little slower, but look well. I find the soil dries out too fast indoors.

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Re: Hardening off

Post by ChilliJez »

I'm away from home for most of each week so hardening off has been a bit tricky. In the end I moved the plants to the greenhouse about a week before the equinox. That should be enough light. I have a bench that has a trough with about 10cm of clay pebbles in the base. I put a soil warming cable in the base, and squashed my vitopod in there too. Then I covered the lot with a drape of bubblewrap.

I hooked up both the soil warming cable and the vitopod through the vitopod's thermostat. Then I tweaked the temp down each week over about 3 weeks. Then I disconnected the soil warming cable so the vitopod base (minus sides) was warming a bubblewrap tent with the thermostat set to 20C. I'm guessing that the vitopod couldn't maintain that temp so allowing overnight temps to fall gradually.

The weekend before last I turned off the heat and transferred DWC plants to a holding tub (15 plants) and potted up my (slyboy's) quadgrow. Last weekend I put the first 10 plants out into homemade SWPs in my Mum's greenhouse. (10 plants) and my Go Massive! BOC went out before that too. So I'm committed to it being ok from now on and I have managed some kind of transition to cooler temps. We'll see.

Now is the time when I wish I'd asked for a max/min thermometer from Father Christmas. I fail to do that every year.

I dream of the day when I can sit here, 200 miles away and log into the greenhouse and check progress. Webcam, dataloggers...Sigh!

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Re: Hardening off

Post by Bigwelshprop »

All my over winters, which include annuums, chinenses and one pubescens are now in big planters or in soil in the greenhouse. I am going to just hope that the forecast for some overnight temps of 3 degrees is exaggerated.

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Re: Hardening off

Post by snagglepuss »

mine went in the greenhouse on Sunday night temps have dropped to 4 & day times have been in the 40's

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ChilliJez
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Re: Hardening off

Post by ChilliJez »

Bigwelshprop wrote:All my over winters, which include annuums, chinenses and one pubescens are now in big planters or in soil in the greenhouse. I am going to just hope that the forecast for some overnight temps of 3 degrees is exaggerated.
Those big planters will be heatsinks helping to mitigate temperature changes. If you had a piece of horticultural fleece (good size 99p, Home Bargains) that would help too.

From your overwinter mentions it sounds like you're experienced. I'm guessing big welsh prop is a Rugby reference. So we won't mess with you then! :lol:

Welcome to the forum. :P

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Re: Hardening off

Post by Bigwelshprop »

ChilliJez wrote:
Bigwelshprop wrote:All my over winters, which include annuums, chinenses and one pubescens are now in big planters or in soil in the greenhouse. I am going to just hope that the forecast for some overnight temps of 3 degrees is exaggerated.
Those big planters will be heatsinks helping to mitigate temperature changes. If you had a piece of horticultural fleece (good size 99p, Home Bargains) that would help too.

From your overwinter mentions it sounds like you're experienced. I'm guessing big welsh prop is a Rugby reference. So we won't mess with you then! :lol:

Welcome to the forum. :P
BWP is just a forum name I've used on various boards for years, dating back to when I was still playing rugby. Now, the more accurate name would be "Bigfatwelshblokewithdodgyknees"!

I did try to ensure that the big planters would do that and so have huddled them all together to try and increase the thermal mass a bit.

As for experience level, I have loved hot chillis for years but started growing them last season. The over winters are everything I bought as plugs and plants last year and so I am still very much learning as I go.

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Re: Hardening off

Post by TheChileAcademy »

Slow and steady wins the race...
day 1-4 sheltered from wind.....full shade
day 5-7 sheltered....partial shade
day 8-9 remove some shelter....partial shade/partial sun...
day 10.....partial sun...

Monitor it closely...any signs of stress, reassess the situation and move into shaded or protected area....

Whole process should take 8-10 days.

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