One of my favourite perennial vegetables has to be toon, sometimes called Chinese mahogany or “beef and onion plant” which refers to the flavorful leaves that taste almost umami, a bit like french onion soup. It the only temperate species I know from the Mahogany family. Young shoots and leaves have a long tradition of use in Chinese kitchens and are today grown industrial scale as “tree vegetable” in greenhouses all year round. Eric Toensmeier did a review of nutritious vegetables and Toona sinensis came in the very top five of all known edible plants - a so-called “super abundant” species that is high in many minerals and vitamins and comes into the very top in both vitamin A and vitamin E.
Growing-wise it seems to love lots of heat and a sheltered space (veeeery long leaves). My plants grow best in the city garden compared to the colder nursery space.
Here you see the shoots at the perfect stage for harvesting in early May (peak perennial shoots season)
My goal is to get reliably hardy Toona sinensis for my climate. As always with woody plants that are on the edge climate-wise, the challenge is not so much our winters (mild) but that our summers are not hot and warm enough to mature the wood before the onset of winter.
Consider the two 1-year seedlings below. Both about the same height. The one on the right has around 50% green wood on the stem. When frost comes, that wood will almost certainly die back, leaving only half the height for next year. The one of the left has almost fully matured, which gives a good chance it might not die back and thus will continue to grow from the top shoot.
Amazingly, not even the top shoot died back, which meant it continued to grow straight up instead of getting two competing shoots from below as trees often do when they die back. Here the same individual in July 2024 (now in November it continued to grow a meter more or so). I probably reached 4-5 meters.
Grow seedlings first year in large containers in greenhouse (100 seedlings in one box). Next year I want to increase that number to hopefully 400-500.
Select among seedlings at the end of season for early maturing wood. This year I picked out 5 individuals with stronger growth and fully mature stems from those 100 seedlings.
Overwinter first winter
Plant out in spring
Allow the best individuals to grow tall (doesn’t die back in winter) with the hope on getting tall enough trees to eventually get seed
Grow on less-good individuals as pollards (die-back in winter as a form of self-pruning) which makes it easy to pick new shoots. I probably won’t get any seed from them, so the breeding effectively stops there, but I still love to eat the leaves.
I have a single tree that is about 3 years old. Each year the frost kills back the main stem and it regrows from slightly further up. I wonder how that will affect it later on. I planted it in quite an exposed area, with hindsight, a mistake.
How do you germinate the seeds? Where do you get seeds from?
Most of the trees I have planted out behave in this way. Some of them are starting to look like multi-stemmed trees or bushes. I only started grading seedlings this year and expect I will have less of the newer plants behave like that because I’ve selected for early maturing wood.
I ordered seed from Vreeken’s Zaden in Netherlands. You can buy seed in bulk. They use it for micro-greens. Quite crazy. I know one restaurant in Netherlands that feature this plant on their menu, and there might be more there now, but otherwise I don’t know anyone in Europe that grows this plant for market. I think it has huge potential obviously. The seed germinate really well. I think the seed source might be local since they sell it by the kilo if you want.
The seed quickly loses viability. First year I have just sowed them in a warm place (green house) late in season and got good germination. Now I cold stratify the seed 2-3 months after having stored them for a few years to help germination. I soak them for 24 hours in warm water before sowing. Warm temperatures help germination and 25C seems optimal.
I consider getting fresh seed again because this season I had less germination than previous year.
I don’t understand what knotting into a bush mean.
I’m very interested in this species, but I keep on reading that the flavor tastes like onions. Occasionally, though, I hear people saying it tastes like garlic instead. Does it really taste like onions, or does it just have an umami-ish flavor?
I intensely dislike onions, but I love garlic. To me, they taste nothing alike. I think the difference is probably sulfur, because durian and jackfruit also taste like onions to me, and they’re apparently high in sulfur. So if toon has a sulfury taste, I would probably not like it, and if it doesn’t, I would probably like it.
I would describe it as sulphuric. I’m surprised you don’t register a sulphuric taste in garlic though as it contains a lot of allicin - one among several sulphuric compound responsible for that characteristic smell and taste.
Describing flavor has some challenges. For me, the taste of toon reminds me of meaty stock, plants in the Alliaceae, browned onions and maybe fried butter. Deep flavors. It probably doesn’t contain any glutamates (signalling true umami) but flavor compounds that remind us umami, which psychologically gives you some of that experience. I would recommend you to try it and judge better yourself whether you like it or not.
A question I’m looking for an answer to: When does Toon typically come into bearing, ie. how old or tall does the tree typically grow before it will set seed?
Bumping this thread because I still have the same question as above. I think I might have one significantly more cold hardy individual. It hasn’t died back this winter like the others, not even in the top bud. The tree is now about 5 meters tall (grew 3 meters last year) still only one single stem, with no side branching. It is quite peculiar. Just looks like a flagpole. I’m curious when I can expect Toona sinensis to come into flower.
I’ll try to ping @VeggieSavage for good luck - is this one of those detective tasks that are within your range?
Two out of three of my Toonas that I grew from seed last year and planted out in the back of the garden survived the winter no problem. The third one might still be alive as well and just has lost the top bud. I will soon see if it sprouts from lower down the stem. The fourth one was in a pot and dried out during our 6 weeks of no rain from February to April. I have started the seedlings in February last year, had them on the windowsill and then in small pots in the garden where I lost about a third to slugs. I planted out pretty late. I had one plant that I bought from a nursery a few years ago and I got killed by the frost in the first winter.
I haven’t done much research into Toona sinensis yet. I do know there are some cultivars with very upright growth habbit & some even with Pink Leaves in early spring.
I suspect Summer pruning can help it exit juvenile stage quicker just like with all other fruit trees & create an abundance of flowers.
I planted my toon trees 4 years ago from 18 inch or so bare root trees. They have not flowered yet. They are about 6 feet tall with branching at the top of spindly trunks. I noticed just today that there are 2 suckers coming up around one of them.
This nursery in the UK reports that their 25 year old tree has not flowered.
Where do you see that Burncoose’s tree has not flowered yet? It would be valuable info and I’m curious why. If the tree only gets 15 meters tall and seems to grow about 3 meters/year here, it would peak in 5-6 years. I can’t find the info on that link.
In apple trees, crossing the juvenile into the adult is defined by the number of internodes on the trees. Not the age. Hence why it might take 8-10 years of you grow the tree in a location with little growth and as little as 3 years of you grow it fast in a greenhouse. It could be the same with Toona.
I bought a toon tree a few months ago, put it into the ground, and then we got a frost that killed the top growth, because the nursery sent it actively growing despite the fact that it was March. I sure hope it’ll grow back from the roots!
I’m thinking it should, since it’s hardy to zone 5, and I live in zone 7b. It’ll grow back . . . right?
In other news, I did try one of the leaves, and yep, it tasted like beef and onions! I don’t like onions, so I’m not gonna eat those leaves, but my husband and children do, so I’m hoping they’ll enjoy eating the leaves from that tree.
Another thought is that I have seen it reported that Moringa will flower/produce pods faster if its roots are restricted in a pot. So that also could be relevant to Toon.
I dug up the suckers from my tree. They were sprouting off of runner roots. I put one in a pot to see how it behaves growing that way.
Thanks or the screenshot. The link still doesn’t work for me. I’m curious how they describe the tree “quickly” getting to 30 ft in 25 year. My largest Toon is 2-3 years old and is now 25 ft. I suspect it might grow another 10 ft this year. I have no idea if height will help it leave the juvenile phase, but with so many other trees that seems to be the case.
I sure hope it’ll grow back from the roots!
