The Tropical Fruit Forum

Some years ago I bought some Autumn Crocus bulbs (=colchicine) and mashed them up in our kitchen liquidiser. I did then get a bit scared about this having read how dangerous colchicine is, so I washed out the equipment several times and never told my wife!
Anyway, I mixed this into a seed compost and planted a load of Poncirus seeds hoping to get some variegated seedlings or other genetic modification. They were all perfectly normal, so I never tried the experiment again. Of course, I've no idea how much colchicine was actually present or how much might be needed to affect the germinating seeds.

Botanical Pilot is right - the problem with purchased PT seeds is the length of time and how they have been stored. If they have been dried and stored like most other seeds they will not germinate.
You need to buy from a specialist citrus nursery or you need to obtain fresh seeds straight from the fruit. These will gerninate easily without soaking.
I often collect a pile of fruit and leave them outside in a pot. By spring they are mouldy and smelly but the seeds still germinate perfectly once they have been removed from the mess. Easier than storing in a fridge for months - which also creates objections from my wife.

There is a very detailed research article about the Beddington oranges at https://www.cadhas.org.uk/app/download/5817192737/Occ+4+Orangery.pdf

These accounts tell a fairly consistent story. The orange trees were planted in the ground and
were covered in the winter by a wooden shed heated with stoves. Gibson says that the building
was over 200 feet (60.96m) long and that the trees were 13 feet (3.96m) high.

One wall of the later brick-built orangery still exists from about 1580.

I tasted one of the fruits and it had the rather bitter grapefruit taste that I remember from years ago. I liked it, but the commercial grapefruit available nowadays are certainly much sweeter and - as Millet says - often with red colour.
quinoah - Citrus here frequently have a second burst of flowering in response to a warm summer, after a cool spring has produced limited flowers. Perhaps that is why it is said to bear fruit year-round. But equally, in cooler climates, individual fruits can remain on the tree for many months.

I bought a Vainiglia a few years ago from Tintori nursery near Florence. I was very disappointed to find the oranges produced were not noticeably less acidic than any other orange variety.
So, either the plant was incorrectly labelled, or the Vainiglia only produces its sweet, low-acid fruit in warmer climates than here in England.
I seem to remember posting about this on a citrus forum and one other cool-climate grower had found the same thing.

I have a Mandalo tree (also called Cocktail Grapefruit) growing in a pot here in the UK. It was grown from seed sent to me from USA at least 25 years ago. Each year It produces a few of the yellow-skinned fruit with seedy orange flesh which is typical of the Mandalo, and is the only grapefruit type citrus which produces edible fruit in the cool English climate.
About ten years ago, this tree had a damaged branch and the die-back spread down one side of the main trunk. However, a new shoot then developed just above the damaged area and its foliage was clearly different from the original tree. The leaves were thicker, darker green and often slightly crinkled with prominent veins. I grafted this shoot on to another rootstock before it also died back on the original tree.
The new grafted plant is now flowering and starting to fruit. The leaves remain as described – thick and dark green. The fruits are still small but currently look more pear-shaped than the original Mandalo.
What do you think this is? It has the characteristics of a chromosome doubled plant, but I can find few references to this happening spontaneously from a shoot.





Mike/Citrange

Check out giant swallowtail butterfly eggs.
See:
https://www.jaxshells.org/70011.htm

I'd like to know how it is that these named varieties of Australian Finger Limes are being distributed in EU countries when, I believe, importation of citrus plants is completely prohibited.
Either they are from illegal imports, or they are grown from seed and therefore not actually the named varieties.

A few years ago I tried growing various citrus seeds in pots containing soil mixed with crushed colchicum bulbs.
First, the bulbs were quite expensive.
Second I got a bit scared after reading
'Colchicine poisoning causes abdominal cramps and diarrhea within hours. Several days later, multiorgan failure, pancytopenia, and cardiovascular collapse occur. Severe colchicine poisoning is associated with high mortality.'
So, I washed out our kitchen blender very, very thoroughly - and never told my wife what I was doing!
All the seeds germinated normally and didn't appear to have been effected at all by the colchicine.

Also if you want to get idiot proof manuals how to use cholchicine with plants, look for weed.

Explain what this means??

Eggeto: I wonder why you are so convinced that you had examples of rootstock incompatibility rather than some other problem?
Once a graft has taken satisfactorily, citrus rootstock incompatibility is nearly always a long-term problem resulting in slow decline, or sometimes unexpected death, but usually only after many years.
Swingle is a vigorous rootstock and I presume the plants seemed OK when you bought them. As you are in Belgium, no doubt these were growing in pots. In these conditions I very much doubt that any rootstock incompatability would be apparent within three years.

All the leaves in your photos appear to have three leaflets, so, as dytandme says, this is either Poncirus or some other trifoliate rootstock. If you follow the main trunk upwards, is there no part which is still producing single leaves? If so, the original top variety could still be rescued by hacking off all the branches that have trifoliate leaves back to the main trunk. This could re-invigorate the top variety if no trifoliate shoots are allowed to grow.
However, the black hole at ground level and split trunk above it, are signs of phytophthera root rot. That's not a good sign. It may not spread or it may eventually girdle the whole trunk and kill everything above. If you want to risk it, you should choose one or two of the trifoliate shoots for grafting and remove the rest.
If you don't want to take the risk, then dig the whole thing up and buy a new tree!

Definitely scale insects.
Scrape them off or use something like an old toothbrush to remove them.
Can sometimes remove most with a forceful hose but take care the water jet doesn't cause damage.
Or spray with horticultural oil at correct dilution.
Neem oil also works, or a homemade white spraying oil - recipes are online using vegetable oil.
Note that oil sprays will kill the scale but they often remain in place and appear much the same as before.

The root rot will only spread if the medium is too wet and lacking aeration. Most of your plant's roots still look in good condition considering that peat and coir can easily stay too wet. It looks like the pot is traditional clay which helps by permitting evaporation through the sides.
When you re-pot (using a gritty, free draining mix) you should only use a slightly bigger container. Going from 20 litres to 50 litres is likely to leave a considerable volume of new mix which can stay too damp because there are no roots to absorb moisture. Roots starting to try and penetrate this region are likely to rot.