Overwintering a Lemon Tree

Anyone?

I doubt a blacklight would have the right spectrum to help it much in growing.
Just did a bit of checking round, looks like it could actively damage it; plants only need a tiny amount of their light to be UV, and too much can cause damage.

Most of my 'indoor plant with artificial light' knowledge is from growing aquarium plants, you can buy plant-rated lights for fish tanks, which I suspect would do just as well for houseplants. Almost all light will help a bit though, especially fluorescent ones, they're closer to the right spectrum, and run cooler, so are less likely to burn leaves.

Sorry, I may have made a mistake with regards to the type of light. The goal is to simulate the summer, keeping the plant warm and avoiding a hibernation period.

You might be better to let them have a hibernation period, rather than force them to keep growing. How many trees do you have, and how big are they?

Two.

One is a seedling, less than an inch tall - I've grown it from a Sainsbury's Basic lemon seed.
The other is a 15" tall tree with roughly 10 lemons on it, all happily on the way to being totally yellow. Purchased from a local garden centre.

You'll probably want to use something along the lines of this:

Lightwave T5 Hydroponic / Aquarium / Reptile flourescent Lighting unit. 2ft 2 tube 48W 3,300 Lumens: Amazon.co.uk: Garden & Outdoors

I got one cheaper off ebay and used it to start off a few chillies/toms this year. They did grow really quick and strong. I could use it to overwinter my orange tree but tbh i don't think i'll bother and let it have an hibernation period.

So is it better to let the tree hibernate, or force it to keep growing? I'm not overly concerned with my larger tree, it's the seedling I'm most concerned about - I starting growing it mid-July so it's only 2" tall at best.

I have lemons, lime, orange and mandarin. All over winter in the greenhouse. I doubt the seedlings will come to much as citrus trees are grafted onto another rootstock, not grown from seed. I would keep your seedling in the house, you never know.

It took the seedling about 4 weeks to germinate, but then we had some fantastic weather and it grew like no other. Sadly, since about two months ago it's stayed pretty standard in its size. It's alive though. Nice and green. Just, not growing.

Citrus can grow 24 hours a day, 365 days a year dark hours and winter rest is not necessary unlike a lot of plants you can `grow them` continuously , but..... to fruit they need a certain number of hours below 12C ( air temperature ) to reset the clock and start flowering again ( you can also do this by stressing them from lack of water )

With a light you need a decent watt one , to keep them happy i use a large CFL bulb that is equiv to 400W watt of normal bulb but uses about 100w of power , i got a dual spectrum one with red and blue light , you need a cfl one as it runs fairly cool , they are about a foot long and 6 inch in diamiter , any hydromponics place should have them

If you let the plant get direct sun or strong light you need to make sure the roots are warm enough or the leaves will fall off with a cfl you should be fine in the house with no added heat

you need either

a) gentle light and a coolish room and no plant pot heater

or

b) a warm room with bright light and a heater mat ( unless the room is warm enough )

They will virtualy hibenate and look realy sad with no light at all , even if very cold ( but to be safe not below -10C ) , they will be fine when it warms up again

At the minute i am back to using a metal halde bulb growlight as i needed more power to do the whole room of citrus , strawberys and tomatos , but it costs a lot more to run it uses about 700watts

Whatever type of light , the main problem is with getting the compost warm enough to stop winter leaf drop when light hits the leaves , do an internet search for ` WLD in citrus ` and theres loads of info ,

Remember to let the air temperature drop below 12C for about 400 hours before the spring , i do this at night so the plant has no light on the leaves when i turn everything off and the compost cools down