Maintain and re-veg a plant over winter?

I posted this in the outdoor sub-forum and didn't get any replies so I thought I'd try here.

I'm an outdoor grower and have a plant I've taken quite a liking too and I would like to try to maintain it over the winter and let it naturally veg again once spring comes.

It doesn't get too cold here over winter. Temperatures drop to an average of 7c (min) and 18c (max) over winter with temps never dropping below zero (freezing). Light levels drop to around 9hrs but I'm not sure how many effective hours it's going to get.

The plant in questions is a pure or almost pure Asian sativa which is ready for harvest around late Nov. / early Dec. It's gone down to 8c here already and the plant seems to manage ok but it does show some signs of cold weather purpling.

So I was wondering if it is theoretically or practically possible to maintain a plant outdoors over winter? Has anyone tried this before? Any tips?

I was just planning on putting it in a greenhouse and hitting in with some Nitrogen / veg. nutes and hope for the best as it's not really possible to do light supplementation for me.

Thanks

Columbo said:

I was just planning on putting it in a greenhouse and hitting in with some Nitrogen / veg. nutes and hope for the best as it's not really possible to do light supplementation for me.

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It could work if the plant gets good warmth and lots of full sun. One thing you could do to greatly increase the chances of success is to give it one flash of strong light every night to break up the dark period. for example, a dark period which is 14 hours long will be effectively only 8 hours long if a strong flash of light is given at 6 hours into the dark period.

Thanks for the tip. What type of light source would you recommend and how long for?

I'll probably just stick her in the greenhouse and try to keep her warm but good to know about breaking up the dark period anyway.

Thanks

Just any strong white light such as a halogen floodlight, and it would only need to be for a minute or two. The specific wavelength which interrupts or prevents the flowering response is red light at 660nm. See the diagrammatic explanation below.

Natural high said:

Just any strong white light such as a halogen floodlight, and it would only need to be for a minute or two. The specific wavelength which interrupts or prevents the flowering response is red light at 660nm. See the diagrammatic explanation below.

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Thanks for the info!

You're welcome.

I thought I'd better offer a further explanation of the diagram and the initiation of flowering in general.

Flowering in short-day plants is controlled by light-reactive molecules called phytochomes.

Red light (660nm), which is abundant during the daylight hours, converts all the phytochome to a state which inhibits flowering (called P-fr).

In the dark, P-fr slowly reverts back to the original state (called P-r).

Flowering in short-day plants is triggered when the phytochromes exist in the P-r state for a critical period of time, and this usually needs to happen over a number of successive nights. Long nights allow this to happen, but if we disrupt the dark period with a flash of red or white light, all the phytochomes are reset back to P-fr and flowering will not occur.

The diagram above also shows that far-red light (730mn) reverses the effect of the red light, converting the phytochome back to P-r following exposure to red light. This effect of far-red light can be used to accelerate the flowering response - a dose of far red light just after the grow lights are turned off in the first week of 12/12 will speed up the initiation of flowering.

Thanks for the detailed explanation.

My plant is already in late stage flower so I guess I'm more interested in the scientific reason behind why an annual plant dies (senescence) after flowering and when winter comes along.

I've heard rumors of these tropical Sativa being grown over a few seasons in their native climate. But am not sure if it's possible or if it's just a case of keeping the plant warm enough over winter or if there's more to it than that.

But I definitely understand what you're saying about the dark interruption and obviously being in veg would make it more likely to survive of winter.

Thanks