cold hardy citrus in full soil in greenhouse

[incubator01]

I'm getting a Kumquat and shikuwasa soon because they're cold hardy for our winters and I don't have to worry too much about the plant dying from the cold (though I will protect it) but I prefer to plant these in full soil, not in containers in the greenhouse (because that's where I can plant whatever i want).
My question is, will such citrus survive warmer summers? Often I have potted citrus that get dried out leaves when the sun shines and the temperature rises above 32 °C, even during heat waves inside the greenhouse it gets to 50 °C.
The greenhouse is 4.5m long, 3m wide and 2.7m high, the sunny side has a shade cloth because the whole thing gets plenty of sun light anyway and has 4 windows and a double door. Naturally I open up everything completely when temps rise above 25 °C but I just want to make sure that I'm not making a stupid decision of planting these in the greenhouse.
As to why I want them in full soil:
- I prefer to limit the  citrus in containers
- Full soil has better moisture management and root development for long term
- no need to hassle with giant containers in the later phases.

[Ilya11]

 I guess that with proper ventilation and shading you can avoid +50C in the greenhouse. Most citruses will not survive such heat.
As to the winter, unheated greenhouse is not particularly effective under long anticyclonic freezes. Kumquats are rather hardy, but only at   vegetation rest. They are late and fruits will be damaged before ripe.

[poncirsguy]

What kind of kumquat are you getting.  My kumquats produce fruit January through March.

February picture

[incubator01]

What kind of kumquat are you getting.  My kumquats produce fruit January through March.

February picture

I'm getting the Fortunella Reale, oval kumquat.

Our winter temperatures usually float around -4 to -7°C but last winter we had an exceptionally cold one of -10°C.
I was going to cover them up with a fleece cover regardless but still, the summer is worrying me more.
I do not have the accommodation or space to place ventilation systems in the greenhouse. Only the 4 windows and double door to open up.

[maesy]

Why don't you plant them outside and just cover them for the occasionally cold nights you can get?

[kumin]

If trees only need short-term intermittent protection, they could be planted under a skeletal framework, then only covered when then need arises. Having a durable skeleton would provide rigid protection against snow and wind. Having removable cover materials would allow for all the ventilation needed. 

[incubator01]

Why don't you plant them outside and just cover them for the occasionally cold nights you can get?

First of all not every part of my garden is for me alone, that's why I have a greenhouse. This means I also cannot plant them outside and build a rigid construction around it, because the heavy wind in january / february would blow it away if these parts are removable. (Yes even the roof of my garage got lifted by the wind once)

Second, it rains a lot here, when it does, it rains for 3 weeks pretty much non stop. Any citrus would drown in it. No matter how well draining the garden soil would be.

[poncirsguy]

incubator01  Are you near a bridge to far.  Does your kumquat fall under the name of Nagami.  Nagami kumquats handle high heat very well. A picture of an 8 year old seed grown Nagami kumquat I gave to a friend 7 ears ago

[incubator01]

incubator01  Are you near a bridge to far.  Does your kumquat fall under the name of Nagami.  Nagami kumquats handle high heat very well. A picture of an 8 year old seed grown Nagami kumquat I gave to a friend 7 ears ago

No, it's latin name is Fortunella Margarita.
That plant looks very nice, I'm also growing a few kumquat from seed, just to see what it will do in many years