UKH

I have fond memories of eating oranges fresh of the tree in Florida, and lemons fresh off the tree in Sardinia, but as much as I'd like too I can't really move to either location...

So, I would like to grow a well fruiting pair of orange and lemon trees in the greenhouse I'm putting up.  From what I've read, for this to work the greenhouse has to be kept heated to a minimum of 7°C to 10°C throughout the winter.   To me this seems criminally wasteful of energy to say the least.

It got me thinking about building a "greenhouse within a greenhouse" during the winter, perhaps a free-standing cuboid with sides of rock-wool containing grow lights with local heating,or perhaps having internal clear plastic dual-layer walls to put up in winter around them, with insulation under the concrete base of that section.  Either way there would need to be some sort of ventilation; I was thinking of counter-flow heat recovery ventilation, perhaps incorporating a Peltier to make it more compact, with the inefficiency of the Peltier providing the additional heating to hold it above ambient. 

The botanic gardens I've visited have always just gone for an egregious waste of energy for their hot-weather sections.

Hope to collect some good thoughts and/or experiences from the hive mind!   

Growing 'citrus fruits'?

And with that m'lud, the defence rests...

I think Monty brings his indoors

I know of a lemon tree that survived and fruited from 1920 to ~2000 in Herefordshire in an unheated greenhouse if that helps? 

We run a cold house in winter with open windows and blankets/jumpers rather than heating so that doesn’t really work.  Also the greenhouse is on a different level to the house so moving trees doesn’t work well.

It only helps if you have a graft or clone…

I suppose I should look at hydroponic orange trees!

Tbh I would think that it would probably be cheaper to get a discount flight to Florida, eat your fill and return via Sardinia, ditto ...

The stuff you ate on holiday never tastes as good at home, no matter how hard you try!

Mum and Dad live across country from you in East Cumbria and have had some success in their conservatory (or "The Orangery" as dad insists on calling it).

The problem I think is the length of the growing season, they have and orange and a lime, both of which flower like crazy but only produce a few fruits each year if they're lucky

However miniature varieties, the type available in B&Q and IKEA grow an absolute treat and seem to produce year-round. They're often a little sour to eat but make excellent marmalade.

So, the ultimate long game ends.. after 16 years!

chapeau.

I have a lime tree that goes down to -5. You can get orange and lemons on the same rootstock. You ain’t heating a greenhouse in winter unless you also have a money tree! Or a constant supply of fresh manure for a hotbed. Just get one that’s good to -5 and if it gets around zero wrap it in multiple layers or fleece and get one of them insulated pots for it. And if it’s gonna get really cold bring it indoors. 
 

worth it as the limes from my tree are unreal. Admittedly I only get a few margaritas a year from the whole tree but they are worth it 😂. 

Remember we used to grow pineapples in this country.....

All it takes is a cunning hypocaust design and a team of gardeners shovelling horse shit 24/7

Sorry it died of frost in the end!

I saw another in Gloucestershire with lemon on at Christmas. I can enquire.

the best example of this is First coffee of the day with a sol y sombre .

https://en.m.wikipedia.org/wiki/Sol_y_Sombra

Hydroponically grown money tree? now there's a good idea

Seriously considering retiring to Spain now

Mum uses one of those cheap collapsible plastic greenhouse thingies inside the greenhouse for more sensitive plants, you could also add the bubble wrap greenhouse shading to increase insulation.

I think he's hoping it'll last more than 40 minutes!

Put some grow lights in the loft and then put the plants in there.

You will, as has been intimated, make a law enforcement officer's day.  But you may also get fruit.

T.

And you'd like to move to Florida?  

I'm sure this is a spoof post.

T.

I might have been a tad ironic there.  The “pros” column has “orange trees in it”.  The “cons” goes on a bit…

In reply to thread:

Thanks for all the replies.  I’ve been laid low by an awful cold and have mostly been asleep but I hope to reply to folks tomorrow.

LED grow lights have improved a great deal these days to the point that they are worth considering but energy costs have obviously rocketed. The energy cost of a 12 hour light cycle on a 6m2 area are still way more than a hobbyist contribution in my view but I suspect there’s a sweet spot for a smaller area suitable for a lower powered set up, enough, say, for just one tree. Producing fruit in a loft or basement just isn’t the same as a tended garden imo but it depends on what you want from the enterprise. 
Don’t forget humidity in lofts needs a solution too.