The Tropical Fruit Forum

leaves don't look very yuzu, but how do they smell when crushed?
I could see some nice bergayuzukosho being made from the peel.

I guess my first question is, what the heck is a Citrum?

I did read up on why or when should a fruit tree start fruiting. Since I'm an engineer I do like to research anything that gets me interested in how it is made, to solve a problem.

It seems you do need energy from the sun (or equivalent lighting) to give the plant energy stored in the roots to be able to change from juvenile stag to mature stag which will allow buds to have flowers, then fruit. Also, there are studies showing a tree needs a certain number of leaf nodes on the same branch (e.g.  apple seedlings didn’t flower until they reached 77 internodes and didn’t fruit until 122 internodes). So, it might be a good idea to put it near a window with good sun exposer, don't cut the central leader, use larger pot, and proper fertilizing might get it going.

You're question "Do you have any other suggestions for encouraging it to bloom this spring?" isn't easy to properly answer by anyone. There are other fruit forums that have been discussing this question of how and why fruit trees transition from juvenile to mature stage for 2 years now and there is no definite answer yet. It's a good question, but no easy or right answer for you.

Citrus from seed have a long juvenility period and I remember Millet saying before that grapefruit has one of the longest.  Another forum member Laaz had one from seed in his yard that fruited heavily but it was much larger than the one in that container.  It might need to get considerably larger to bear fruit, but I can't really say how much.  With so much time invested in it so far it sounds fun to continue the effort.  The trees do look nice.

Hello everyone, I am pleased to show you another of my achievements this year. It is a hybrid of these two species and for a while I suspected that I had mixed up the seeds, since I also have a kaffir lime. Now that it is flowering, I see that the buds are almost identical to C. maxima, which clarifies the relationship.

I have discovered, through my practice, that the characteristic aroma of the kaffir lime is a very intriguing thing. It is not the smell of lime per se, but a particular characteristic, a smell like the "essence of lime", something more synthetic, very intense. I have made crosses with lemon, some of which did not inherit that smell, crosses with limequat, with kumquat and many did not inherit it. Until one time I smelled the leaves of a rare grapefruit that had a different fruit, and its seedlings smelled like a kaffir lime. Also when I picked the fruit of C. maxima, I also perceived it in the wound at the end of the fruit. My conclusion was that both plants must have the expression of that chemical substance in their genetics.

To conclude, I continued my experiments and crossed C. maxima x kaffir and analyzed the seedlings... it's strange that many of them didn't smell and others did, the same thing that happened to me with the lemon 🫣... Ultimately, I don't know how that genetic explanation works, but it's all a mystery. Perhaps an ancestor of both had that genetics and that's why it's in both in different measures and at different stages or parts.

In short, here I bring you this plant:

,leaves with short petiole sometimes subtly winged or wingless (like lemon), thick green leaves like C. maxima, more intense anthocyanin buds than lemon 🤷. flowers in clusters like C. maxima, slightly anthocyanin in bud stage. sizes of the same close to C. maxima. few thorns. its leaves smell like kaffir lime.

It flowered exactly at 4 years old (its siblings have not yet). If grown vertically, it reaches 3 meters in height (the technique is called Res, I call it "vertical cultivation").

Alexmed95,
Sorry to intervene here, but since your are in Québec, you are aware that in French citron means a lemon. Are you sure that what you bought is not just an Amalfi cost lemon?