The Tropical Fruit Forum

Yes I have heard of it but never eaten it. I have been to Tokyo, but did not find it in shops. It is famous from Nagasaki area ?

It works so well that here on a sunny cold day it’s -30f outside and over 80f (26c) inside.

How do you go with condensation drip or ice formation on the inside roof ? It is a problem here with frost in unheated plastic tunnels at below zero.

Shade houses, and irrigation, hand watering to soak them up. Overhead sprays to stop them drying out quickly.
42'c is not uncommon but we haven't had a run of them for a while. If the nights stay hot that is what dries them out the most if you don't watch out for that.
Then to relax go home and watch some movies about really cold places about - 30'c,  or reruns of The Beachcombers TV series, salvaging those logs with their speedboats.

I have found the fruit in Nth Qld. The fruit are large, tennis ball plus. The pulp tastes like weak seedy black sapote, or a bit like wood apple pulp. Interesting, edible not the greatest, but has beautiful scented flowers. It grows right on the beach, mass blooms with that gardenia scent, romantic nights on a tropical beach, oh the memories.

For commercial Citrus rootstock seed production I don't think there is any attempt to exclude pollination from other nearby rootstock Citrus types.
That is in mixed plantings or rootstock seed trees, including FD and PT.
Off types may need to be removed, but the seedlings are usually highly uniform for rootstock use.
I have found variants in rootstock seed, but never thought they were pollinated hybrids.

I do use an ec meter for my fertigation (add small amounts of liquid fertillizer every time I water my small container fruit trees) and try to adjust it based on some salinity tolerate tables I found, but I’m not sure how that translates to organic fertilizer as there is hardly any sodium
Or chloride in it.

NaCl has an EC, but so does CaCl KCl CaSo4 MgCl MgSo4 etc etc all those similar fertiliser components for the purposes of liquid fertigation
Even Urea CO(NH 2) 2. has an EC equivalent, although it is not exactly the same type of molecule as the others.
Organic fertiliser may have more complex larger molecules, but they probably eventually break down to smaller types like above.
On top of that your water has some level of EC before you add fertiliser.
Not a big problem, but keep in mind that fertilisers have an EC effect.
Also if you apply fertiliser to a pot and it dries out the EC increases in the remaining soil water.
That is why some fertilisers say don't apply in high temps, more so if the are heat release types.

Hello and thank you for the message. Can you also supply seed of  Kawabata or other Japanese Citrus ?

A standard toxicity test is to plant 100 radish seed in a pot and count the germinations. High rate = very low to zero toxicity. Low rate of germination = higher toxicity.
You may need to standardise by knowing the germination rate of the radish seed, that should be 100% in most cases.
You could test toxicity of your fertiliser on radish seedlings in pots, if they go backwards it should be an indication.

I purchased a composted and mineral blend / humane fertiliser /  from a company that promoted the Brix idea to Australia.
I was happy with the plant response, but also later added some regular NPK to get some of those levels up.
In soil less media I was using Osmocote plus micromax for trace plus some iron and lime dolomite.
Overall I thought that bombed out after a while, and the organic amendments seemed to get it going again without repotting.
Once I did notice the full product range from a high NPK fertiliser company, it also included fungicides and insecticides etc to manage the plants grown that way.

Personally I didn't ever try to measure Brix, it could be an interesting tool.
Fertiliser is big business and all are profiting from promoting what they sell.

Humates and Organics have become more mainstream, and retaining soil Carbon on farms is now widely accepted, if not essential.
Years ago this was crackpot hippy nonsense, but now is fairly well accepted and practised.
This fertiliser contains osmocote prills and organic type pellets.
https://gardensuperstore.com.au/osmocote-plus-organics-all-purpose-including-natives-plant-food-soil-improver/?sku=120100&gclid=Cj0KCQiA_bieBhDSARIsADU4zLeaoW7zUtH34hMTtT9Ye3O9i7aATIfqfOec0RN52vPJQoSy-9XGmTMaAppnEALw_wcB

I think there was a discussion on the Citrus section about feeding nutrient solutions to albino Citrus seedlings. This kept them going for a time but they didn't recover chlorophyll.

I guess Nitrate is the form of Nitrogen. Common forms are Calcium Nitrate, Potassium Nitrate.
There are other N forms such as Urea.
Ammonium Nitrate would supply N in two forms, but lower Nitrate % than straight Nitrate forms for the same total N.
There are also newer slow release complexed N forms that need to break down to release. These are large N molecules, often used in pot mix to time release.
Organic forms can be slower release, lower Nitrate.

The label of the fertiliser should detail the Nitrogen forms that give the total N for the 6-4-6 or 20-10-20
It should say % Urea or % Ammonium nitrate
High Potassium fertilisers could be Potassium Nitrate based as fertilisers are made to a formula to get the NPK and micro balanced
This is the easiest way to get high N high K.
Organic forms can be slower release as discussed above.

Nitrate has problems, but so do Urea and Ammonia in high doses to plants.
I have made a few bungles by charging off on a new direction.
My policy is now add less fertiliser apply twice and see what happens.
I have also repotted with high fertiliser, only to get super growth and pots outgrown quickly.

Apart from Brix to plant health there is also this.

High levels of nitrate in vegetables are frequently reported. The potential hazard of vegetable-borne nitrate is from its conversion to methaemoglobin-producing nitrite before and/or after ingestion. Methaemoglobin cannot bind oxygen and produces a leftward shift in oxygen-dissociation curve, causing hyperaemia.

https://www.horizononline.com/nitrogen-in-slow-release-fertilizer/
https://pacificfertiliser.com/slow-release-nitrogen/3311/

The pigmentation does affect the taste.
The more pigment the more it moves toward stronger flavours, less " orange" flavour.
A purple black pigmented Moro gets toward unsweetened dark chocolate flavours, raw beetroot flavours.
Less pigmented light blood taste closer to orange or Vaniglia.

Arnold Blood a seedling of Moro produces a crop of highly variable pigmented fruit, ranging thru the flavour / pigment spectrum on one tree.
https://www.google.com/search?q=arnold+blood&client=safari&rls=en&sxsrf=AJOqlzUhtJLRSEeQ3PcoKl6PLOFfZnmv4Q:1674333741451&source=lnms&tbm=isch&sa=X&ved=2ahUKEwj_5pOfw9n8AhUIyzgGHSGPCegQ_AUoAXoECAEQAw&biw=1641&bih=892&dpr=1#imgrc=YCtooDn44hvSaM

You could always buy somewhere that is marginal for Tropicals and wait for the zones to migrate to you with climate change ?
We haven't had as much frost here for years, which is great for those on the tropical subtropical cross over.
Unfortunately with the mild winters, fruit fly doesn't get a cold knock down so it is getting tough growing without screening.
I am in Australia, we also got an influx of fruit eating rainbow lorikeets about 5 years back from somewhere. Now large flocks all over town.
.https://en.wikipedia.org/wiki/Rainbow_lorikeet
Beautiful birds but they hammer fruit trees in flocks.
The local wild parrots were usually only visiting in pairs on this property, so only a few eating some fruit on the top of the trees, no bother.