About 8.5 years ago I successfully germinated a lemon seed from a store-bought lemon (I believe it was a Eureka lemon). Fast-forward to today and that lemon seed has grown into a 9-foot tall tree. Luscious green leaves, 2-inch diameter trunk, several branches, it would probably be over 10-foot tall if I never pruned it.
Things to keep in mind:
To this day I have not seen this tree produce a single bloom.
This tree lives in Pittsburgh, PA and spends its time indoors October through mid-April.
It receives as much sun as possible when outside. While indoors, I have it seated on a heating mat with white LED grow lights 10-12 hours a day and the indoor ambient temperature ranges between 62F - 72F.
I have never left this tree outside during a frost. Obviously citrus trees do not grow this far north so I had no viable scions around me. Therefore my lemon tree is not grafted.
2 - 3 times per year this tree will go through a rigorous growing phase, putting out new shoots on the upper branches. I usually have to cut some of these back to allow the tree to fit in the house. I have been told the highest branches (i.e. the newest branches) will be the first to produce blooms. Hopefully, I am not cutting the branches that would produce a bloom???
The leaves emit a strong lemon scent when torn or ripped.
The tree is fertilized every 3 months with 1 Tbsp of CITRUSGAIN (https://www.bgi-usa.com/citrusgain/). The tree is watered with distilled water and/or rainwater 2x/week, I allow the soil surface to dry between waterings. But for the past 10 months, I have watered this tree with a mixture of 5 tsp Tiger Bloom (https://foxfarm.com/product/tiger-bloom-liquid-plant-food) per 1 gallon of distilled water. I have heard the high phosphorus content could help promote the growth of blooms.
Is it possible that this tree will eventually produce blooms? I understand that without grafting, I am not going to see the same fruit that the seed came from, but instead some lemon/citrus derivative, that's if it ever produces. I have heard that a non-grafted tree like this may take up to 15 years before it produces any blooms or it may never produce a bloom...ever! Some farmers have told me to expect blooms during the 5th year. As I mentioned above, I have to cut the newest branches to allow the tree to fit in the house. Is it possible to graft those cut branches to a lower section of the tree and allow the branch to grow out and possibly produce a bloom?