I have a 20 by 30 hoophouse in zone 7b (Raleigh, NC) and my citrus do fine most of the time. I have two small electric heaters running most nights and when it calls for below freezing temps I use a wood burning stove. The wood stove can really crank out some heat but you have to baby it all night long - hopefully I will get better at it over time. Some of the citrus decided to suffer this year (even though it has been mild so far) so I have rigged up a tent inside the hoophouse, a sort of greenhouse inside a greenhouse. I put one of the electric heaters in it and run it all the time - so far it seems to be helping. You could partition off sections of your structure so that one section is super heated while others are not and keep the really delicate stuff in that section. Heating the hoophouse is not the problem. Keeping the heat inside is the big problem. Plastic sheeting just doesn't hold on to heat very well. You can allow things to cool down to the point where your plants go dormant and then you can lower the light levels by covering the structure with a pool cover or other sort of thermal covering. You can eventually get the covering built up to the point that the whole thing keeps itself warm - but you won't have much light which the plants need to stay active. But by encouraging them to go dormant (dry, cool and dark) you won't have to do much work and often they survive til things warm up in the spring. All of this falls apart if you want to grow crops at the same time. If you increase the light levels enough to encourage growth then you have to keep the space much warmer. I have all sorts of citrus and they do not always follow the rules - some that are supposed to be delicate have no problem with winter cold while some that are supposed to winter hardy almost die each year. Some do fine for years and then all of a sudden go downhill, so you have to be flexible. It can be done, but it does require a bit of planning and work. If it was easy, everyone would have citrus in their gardens.

I too love birches and would love a little wood of them. I would plant Scottish bluebells under them en mass. A seed trading friend of mine in California sent me three bags of birch seeds (besides the ones I got myself from the little tree at Lowe's). They are European Birch, White American Paper Birch and one other that I cannot recall off hand. I read that they had to be fresh or they wouldn't grow, so I didn't planted them. But now, I think I will go ahead and try sprouting them. What have I got to lose? I think if I put them in very soggy paper towels and stick them in plastic bags, they should sprout, as that is where they sprout best in their natural environment - on the banks of brooks and rivers where it is very wet. Worth a try. Eduarda, I appreciate your input. Muito Obrigada! ~Annie

Cold weather citrus info- http://www.justfruitsandexotics.com/Citrus.htm Kumquat- http://www.hort.purdue.edu/newcrop/morton/kumquat.html Kumquat- http://en.wikipedia.org/wiki/Kumquat Satsuma Mandarin- http://plantanswers.tamu.edu/fruit/satsuma.html Satsuma Mandarin- http://www.floridata.com/ref/C/citr_ret.cfm Calamondin- http://www.geocities.com/verymad_scientist/ Calamondin- http://www.hort.purdue.edu/newcrop/morton/calamondin.html FRUITING SCHEDULE-http://www.growquest.com/Fruit%20trees%20-20better%20plant/citrus%20harvest%20times.htm I also grow persimmons, pomegranate, strawberries, Rhubarb, Avacado's, a dwarf banana tee, and a dwarft apple tree I got from Michigan bulb(5th yr )and I aso do patio blueberries, and a American Hazelnut tree.

It can be done. My own experience was starting seeds from lemon and oranges in soil, then moving them into rockwool blocks after maybe a month. The rockwool blocks were put placed in GH waterfarms with hydroton clay pellets. It was fun and surprisingly easy. I still have maybe four trees, all in soil at this point, alive after maybe three or four years. Keep an eye out for mealy bugs and fungus gnats.