northern citrus

[strider3700]

I just thought I'd share what I do to have a lemon tree in ground above the 49th parallel.



It's a small wooden frame with standard poly for glazing. I've wrapped a coil of those cheap rope lights around it for cold nights. The tree should be good down to about -5 C without protection. I put the tent on if it's going to be near zero or worse. The lights get plugged in if it's going to be negative temps.
last night it was -2 and the temp inside the dome was +7. It's supposed to hit -7 tonight and -8 tomorrow so we'll see how it holds up, I may need to add an insulating blanket (old dog blanket).

This should be enough to get me through until things warm up again near the end of the week. When the tree gets larger I'll need a larger tent but the idea remains the same. The tree will also be tougher and the outer tips will be the parts to worry about not total death of the tree.


There are others in vancouver and slightly north of me on the island growing outdoor citrus and we all do the same. As far as I know we're pretty much the furthest north outdoor in ground citrus in the world.

[RobertSmalls]

Wow, I didn't know you could keep tropical trees alive outside in BC. Is it going to need a tree-sized cold frame when it's an adult?

I think cold frames are a really neat idea, and I've been thinking about using them to plant my garden earlier next year. Have you thrown a thermocouple inside yours?

[strider3700]

yep it will need a large frame when fully grown. I placed it pretty close to the house which will force me to keep it pruned to a small 5' maybe 6' tall size so the frame won't be too insane.

I haven't put a thermocouple inside but I have been using a regular thermometer and my IR gun regularly. The IR gun is what gave me the temps in my first post.

Tonight they have announced -8 with a windchill of -20 which is unheard of for around here so I added a blanket and used snow to bury all the way around the base. At this point the tree will remain sealed up until it warms so hopefully it does OK. a thermocouple would be awesome right about now but my arduino just shipped from Hong Kong this morning....

[Daox]

lol that is awesome!

[RobertSmalls]

I bought a couple of $10 corded indoor/outdoor thermometers that I use for all sorts of projects like this. Which reminds me, I have one taped to my hot water tank right now.

[Daox]

Got a link to what these corded thermostats you're talking about?

I also have northern citrus. Its a small tangerine tree my wife got me last year. Mines almost ripe enough to pick too! But, I move it indoors when fall rolls around.

[RobertSmalls]

You're planting ideas in my head, Daox. Mostly ideas about starting fruit trees from seed in 5 gal pails, and hopefully moving them to a more permanent location when I move in a year or two. How tall was the tangerine when you got it?

I actually can't find the thermometers for sale on Amazon, but it's something I saw at Ollie's (closeouts / wholesaler / junk store) and bought a couple of. It's just an indoor/outdoor thermometer, but with the outdoor on a 9' wire.

[Daox]

Ah yeah, I know the kind you're talking about. I was thinking of something else.

The tree has probably grown about 1 foot in the past year I'd say. Its roughly 5.5 feet now. I was very surprised to see it bear fruit the first year we got it. It takes almost a year for the fruit to grow and ripen. Its been growing in size since spring and in the past few weeks has finally turned color.

[basjoos]

I'm not growing northern citrus here, but have been experimenting with growing citrus north of the usual citrus range outdoors under winter protection here. I'm growing a number of outdoor citrus here. In the unprotected category are the 20ft high citranges and citrumelos that I have been growing for years. They'll defoliate on bad winters, but otherwise do fine and fruit every year. Recently I've started growing several cultivars of satsumas and the Hamlin orange under winter protection. Both of these mature their fruit in Sept through Nov, so I'm not having to overwinter frost-sensitive immature fruit. I'm overwintering them in cold frames on the raised beds in my vegetable garden where they are planted in the beds. The cold frames have insulation and heat storage on their north sides and provide about 20 degrees F of protection and is a design I've been using for years to grow tomatoes and potatoes through the winter. I'm espaliering the trees to keep their height within the maximum height (6 feet)of the cold frame. I got a few satsuma fruit off them this fall and hope to see more in years to come. One of the satsumas, Miyagawa, is naturally dwarf with a mature height of 8feet.

[Asyme]

Hi, new from Sydney, Australia and I am really liked this idea and I want to celebrate Christmas with my family outside and we want lighting for outdoor decor. I am not very expert in this citrus work. Is there any other way to give power to lights like from Car Battery?