leatherback
The Treedeemer
my recommendation would be to create a thread for your question instead of adding it to an old dormant thread.
Force Larch to come out of dormancy
- Thread starter Nishant
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Hmm.never heard that larches would survive under growlight in dormancy time. But maybe its possible. Good luck and keep posting here how your larch is doing
Leo in N E Illinois
The Professor
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You are in a warmer area of the UK, if it were me, I'd leave this larch seedling outdoors, Even though it did not sprout until July it should have no problem surviving your mild winter and sprout with vigor in spring.
If you feel you must bring it indoors, you might be able to get away with it because it is a seedling less than one year old. Older seedlings will require a winter dormancy.
But if it were me, I'd leave it outdoors.
Sootys trees
Yamadori
Thank you, and me neither lol, I’m pretty sure that’s because they are supposed to be outside, but given this one’s age (4 months) I was hoping to give an extended growth period because it came up late… now I’m thinking outside might be better. I have no experience in the matter, just experimenting.
Thank you jelle, I may do, but it was just the one question i wanted to ask and thought it was the same subject matter. I mostly read and learn, I rarely give advice as I’m fairly new to the hobby, everything I know is from other members on here. I have lots of questions!
Thank you
I was expecting this answer and I do know it should be outside, I just thought a late one might need to harden up a bit more etc before a cold spell… as I say it’s a 10 pence seed so no biggy if it dies…
It’s just very fascinating for me to watch it grow over winter !
Thank you for the advice it’s much appreciated
Deep Sea Diver
Imperial Masterpiece
Love old ‘dormant’ threads as sometimes these threads can be infused with current knowledge or more depth of experience in a specific area.
FWIW roughly any tree or shrub placed in our ‘cold’ greenhouses (properly maintained and ventilated) gain about 1-1.5 months on the growing season with no adverse effects on the plants.
Pretty easy to measure as we have trees outside mulched in under cover, others mulched in but exposed to the wind and sun. Also trees in a large vinyl cold frame in shade and trees in two smaller greenhouses.
We don’t intentionally force trees to come out of dormancy. These trees do what they do.
Normally a larch would not go in the greenhouse, but it has happened. That’s due to our practice of placing young stock acquired late, injured, weak, or recently heavily worked trees (wired or pruned) in the late fall in either the greenhouse or cold frame.
In the larch situation, both larches greened up about a month early.
Thus, if one is well versed in the downside issues of keeping plants in a greenhouse during the winter, it is possible extend the growing season for a tree….
If one did they would be wise to properly harden off the plant before bringing it outside full time.
Just my two centavos…
Cheers
DSD sends
FWIW roughly any tree or shrub placed in our ‘cold’ greenhouses (properly maintained and ventilated) gain about 1-1.5 months on the growing season with no adverse effects on the plants.
Pretty easy to measure as we have trees outside mulched in under cover, others mulched in but exposed to the wind and sun. Also trees in a large vinyl cold frame in shade and trees in two smaller greenhouses.
We don’t intentionally force trees to come out of dormancy. These trees do what they do.
Normally a larch would not go in the greenhouse, but it has happened. That’s due to our practice of placing young stock acquired late, injured, weak, or recently heavily worked trees (wired or pruned) in the late fall in either the greenhouse or cold frame.
In the larch situation, both larches greened up about a month early.
Thus, if one is well versed in the downside issues of keeping plants in a greenhouse during the winter, it is possible extend the growing season for a tree….
If one did they would be wise to properly harden off the plant before bringing it outside full time.
Just my two centavos…
Cheers
DSD sends
Orion_metalhead
Masterpiece
What species is the seedling? Collected in July should ve enough time for a seedling to stabilize before natural dormancy cycle.
Sootys trees
Yamadori
Old threads have some of the most knowledgeable content,
And Thank you that is some very sound advice,
I have lots of larch 2-3,4 years old, all of which are in the ground so other than mulching I’ll not be doing a great deal to them regarding protection just some mulch as they were only planted this spring.
The small seedling however popped up around June from seed, After it stopped growing / elongating I brought it in under a full spectrum grow light, not from fear of losing it (although I had doubts it would survive without a cold frame), but just to see if I could continue its growth over winter to then introduce it back outside when the temperatures and weather is appropriate, ie spring after last frosts …
I would of course harden it off before introducing it to full sun exposure… I think given the seedling is barely 4 months old and it’s not had much of a growing season, it might bounce right into spring and grow without being dormant this year for one season … then of course it would spend the rest of its life outside…
I’m not trying to go against any horticultural knowledge and implying that larch can be cultivated indoors as plants, I’m just seeing what will happen this once…
I understand people successfully start seeds early indoors for planting out once spring hits to get a head start, its not quiet the same because it’s a long stretch but it’s kind of the principle I was implying… and by indoor seed starting or in this case over wintering a late sprouter, or growing on indoors, I’d being using a full spectrum light …
Thanks again for the information hope this makes sense
Orion_metalhead
Masterpiece
Typically starting seeds waaaaay early inside has a negative effect and it takes a few years for them to return to their normal cycle. This is why many stratify their seeds outdoors with protection or start them close to the time they would naturally germinate.
Sootys trees
Yamadori
Yes yes I’m fully aware of this, thank you I understand what you are saying.
I have researched lots about tree seed starting, cold moist stratification in the fridge and the natural winter outdoor stratification / natural process…
I’ve had lots of great seedlings start out this year, 20 or so black pines, 10 giant sequoia and a few red woods, apples, lemons (now indoors), and many other fruits and trees… also dozens of cuttings to long to list…
The pines and everything else apart from the lemon are fine outside
It’s just this larch came up way to late to survive winter in my opinion, but I may be wrong it might be ok, but buds are now opening under the light and I don’t want to subject it to late autumn, low light conditions now, it’s past the point of return until spring in my opinion…
Leo in N E Illinois
The Professor
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Clearly you have some experience with starting seed. And you have made up your mind as to how to proceed.
Not trying to change your mind, but I would like to point out, Larch species in North America, Asia and Europe are part of the high latitude, near tree line flora. Their natural habitats have some of the shortest growing seasons that trees can be found in. Larches are found in the Canadian artic, Asian, Siberian artic, far northern Europe and Scandinavia and alpine regions where growing seasons are short. This is the reason I said I thought the July seedling would be fine outdoors. Larch are short growing season trees. They can be found in areas with as little as 10 to 12 week growing seasons.
However you have already got your seedling starting to swell buds under lights. This means it is likely too late to put it back outside and have it return to dormancy. Young seedlings are adaptable, you might get away with growing it under lights thru its first year,.
Older seedlings will be less tolerant of indoor cultivation. One issue is larch are adapted to a sharp day night temperature change. They like a sharp cooling off at night. They prefer night temps well below 70 F or below 21 C. Day-night temperature difference should if possible be greater than 15 degrees F or 9 C. This cooling slows their metabolism at night, allowing them to accumulate sugars for growth. Warm nights mean more sugars will be consumed, if too warm, all the sugars from the day's photosynthetic production can be consumed by warm temperatures causing metabolism to run high at night.
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Sootys trees
Yamadori
This is really interesting information thank you, and had I not brought the seedling in i would definitely have took yours and everyone else’s advice… I really appreciate the input, not so much for the tree but for the learning side…
I do know larch can not be cultivated indoors and whenever I buy or start any plants I get as much info as I can,
I want to see how it grow under my full spectrum light instead of shutting it down after what I believed was a late start…
but as you’ve explained their natural habitat and preferences, seasons etc , it might not do so well under my light even though it is a decent one.
The power of the sun is close to 100,000 lumens per square foot I have read, depending on location and intensity of course… so mimicking full sun at home in such a small area would be very difficult, near impossible perhaps ? Even with a full spectrum light such as mine… you’d maybe need 10 or so
The goal in mind was to continue its growth until
Spring which I understand now is a big ask given how long that is away and how short their natural seasons are, but as you mentioned it may be ok given its age, which was the only reason I am attempting this…
So, I’ll see how it goes, see how it elongates, and hopefully introduce and acclimate it next spring, along side some of my larch I’ve left outside…
Again really appreciate the input thank you
Sootys trees
Yamadori
The larch did ok being reintroduced to the garden 6 or so weeks ago and has hardened off well, it’s greened up a lot and has many buds and kept all its leaves… I think it will be fine to stay outside this coming winter… here is a before and after … again this was just a ‘test’, seemed to be fine and luck was on its side, also the age seemed to help it along… 
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