The Tropical Fruit Forum

If you plan to plant them in soil in your unheated greenhouse, the cold and humidity during the winter is going to kill the rootstock.

Quote

Left it outside at 0C

well at near 0 they don't freeze, it has a lot of thermal sink around. But once temps start to be -3C for a day, you will see damage.

Don't worry, I will not plant it in full soil anymore. I planted every citrus in containers, except a kumquat seedling, just for the fun of it
The next nights we get -2 °C so I did cover all of them with a frost cloth inside the unheated greenhouse just to be sure the new growth will not die. I can confirm shikuwasa is a good grower, perhaps a bit slower than others but once it got started it got new buds on many places and grow fast.
As for reference, I was told by a dutch citrus specialist that most citrus were grafted on PT however since I saw many differences on the grafts of the ones on Oscar Tintori's plants I already found it odd. I do know from the same person that Oscar tintori is to be trusted in terms of having good plants, much better than whatever I had before from local stores.
My only issue (personally) is that I should not buy very young cuttings or recent grafted plants, I do not have the proper experience yet to care for them and make sure they survive winter. Maybe in the future

yes, all my citrus are in there and I have watered them two times with very small amount of water, its cold, and is not very bright there so they use very little amount. The kumcuats I havent watered whatsoever , their soil still has moisture from the last watering in the fall ...
I will be taking all my citrus plants and others in a few days and will give them all a nice shower and watering....

That's very interesting to know. I would think the soil would get some sort of fungus from the moisture if it stays wet that long but apparently not
Will definitely try this out next winter!

I have tree  small kumquat seedlings along with a pomello seedling,  they are s single summer old, that overwintered successfully in my basement with very little light and low temps to the point the soil had froze one time , but general temps were around 2-3 c .

I heard people putting them in a basement before, I assume the air is more humid there, unfortunately our basement has no window with direct light, as as dark as hell there (perfect to grow mushrooms though xD) so I don't know if they'd survive 3 months in total darkness.

ok, I'll see how they survive but from the looks of it it wont' be that good.
As experiment I put one seedling in the full soil of my greenhouse, just for the fun of it (I had too many anyway)

I too have a shikuwasa, bought it because it was cold hardy, so far it's been inside the greenhouse protected from snow and cold but it's vigorously flowering and growing new branches.
If I knew before hand the pursha lime would be so extremely sensitive to temperature change (a large tree of 30cm pot size diameter) lost half its leaves due to a hot spring day spike and it could not handle 40°C inside greenhouse) I would not have gotten it and gotten an extra shikuwasa instead, they seem very interesting plants and t didn't suffer at all from these temperature changes

@lebmung : inside air was too dry here, moved everything elsewhere, increased survival chances.

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.

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.

I'm from the flemish part of belgium, i knew about the french forum but my french is too limited for me to make too technical conversations. So that's why I'm here

My pots (the plastic ones) have a lot of hols in the bottom, I drilled 8 extra in addition to the 12 existing. My drill  is a small one so doesn't support 1 cm drills, the biggest it canhold is 8mm diameter.

As for a cheap pine bark compost, the only compost i found in Gamma is https://dcm-info.com/int/en/products/soil-improvers/vivimus/dcm-vivimus
It's not exactly what you mention though, and not very granular either.

The fertilizer i have should do however, the vendor has been using it for years on all his citrus trees and I'm even using it on lemon and limequat seedlings and they grow nice.
But it is true that most easy to get fertilizers are not good here, hence I order the floranid twin permanent elsewhere.
The mix of a commercial substrate plus perlite is also what I do for my seedlings, I use https://www.eurotuin.be/dcm-potgrond-voor-huis-tuin-60-l-92711796?partner_id=commerceconnector&utm_source=TradeTracker&utm_medium=feed&utm_campaign=ShopForward+BE+Shopping

That's what I did with the kaffir an persian lime of which I attached an image, I waited about 3 weeks before repotting, however I'm afraid wrong advise from someone else caused this rootrot. He told me to put pine bark on top of the soil to protect the surface roots and retain moisture, problem is that pine bark makes my soil too moist and even wet for weeks.
I simply hope these 2 will recover permanently from it, so far they went through the worst, but it's still not 100% out of their system.
Maybe yes if I did buy a new one and did it without the pine bark  it would be fine.
However I'd much rather get my hands on viable kaffir lime seeds because I prefer a larger growing tree with thicker trunk than a grafted one, people keep telling me grafted trees don't live as long and are more prone to rootrot.

Hi,

For 2 years now I am tirelessly trying to keep citrus trees alive, but so far I managed to kill 8 already
I buy grafted trees which are probably no older than 2 years from a local vendor who sells exotic plants, he gets them from growers in sicily, Italy.
I bought Kaffir limes, Key limes, persian limes and limequats and from other sellers I bought cuttings of kaffir lime and persian lime.

The internet is full of different kinds of information which is very contradictional and caused much grief.
First trial was with a kaffir lime put in purchased potting mix for citrus plants, the plant was grafted and eventually died from rootrot and armoured scale.
Because people said this kind of soil was not good I found a Dutch site describing to use 50% white sand and 50% compost, but that soil instantly killed the next 2 plants because that soil did not drain at all and remained very wet for weeks.
Third trial was with another Kaffir lime and Key lime using a potting mix of equal parts of perlite, vermiculite and coco peat or peat moss (but I prefer coco peat), that soil appeared to be needed in very hot climates such as South california but definitely not in central Europe, soil stayed too wet because the vermiculite retained moisture too well, but it did drain much better.
However, plants died after a few weeks.
Note that in the second and third trial I washed the old soil off the roots with water, probably this also stressed the plants too much.

Last test I re-used the soil from the vendor's pots and added a bit fresh potting mix and compost, so basically the composition was: equal parts of potting mix (universal), regular soil with sandy structure and I added perlite to improve aeration.
This time I did not wash the old soil on the roots and just loosened the roots on the edge of the root crown, left the soil on the rest so stress would be minimal.
I put it in a pot that was 10cm bigger (wider and higher) than the previous one.
After one week the kaffir lime and persian lime dropped all leafs, some branches turned brown, even though I reduced my watering regime.
I let them dry out (not fatally) and give it little bits of water once a week, then they start to grow new foliage, but more branches die off.
Weeks later the new foliage is nice and big, suddenly the plant stops growing, new buds wither and turn brown, some tiny green leafs fall off.

In  the meantime I also got a limequat, repotted it the same way, it was fine for 3 weeks, then suddenly one day when I was supposed to water it, 90% of its leafs were dried out and fell off. Some healthy ones too for unknown reason.
The food I give them is Floranid Twin Permanent with NPK of 16-7-15, which turns out to be the best slow release fertiliser compared to all other liquid ones I tried.
There were no aphids/scale present on any of the plants.

To this end I am slowly to the point of breaking down and giving up on these grafted horrors. I know growing from seeds is not done in commercial  areas because of viruses passing on but germinating lime seeds is more successful than keeping those trees alive...

But regardless I wanted to find out if there's anything different I can do.
As for the location: 2 years ago I put them outside, that tree could withstand bright sunlight, until I repotted it. After many attempts to get the information out of the vendor, I now put it in my greenhouse (where it's warmer) where there is a shade cloth to protect the limes from burning sun. The roof of the greenhouse has partially filtered glass so no bright sunlight can get in. The vendor told me he put them in there too with similar conditions, even when it was very hot.
So it is sheltered from wind there and gets filtered sunlight, protected from the western sun.

Attached are pictures from a kaffir lime, persian lime and limequat as they are right now.
-> Kaffir lime

-> Persian lime

-> limequat