I have a potted lemon tree grown from seed, about 8 years old, lives outside in the summer, inside in the winter. It is lush and healthy looking, but doesn't flower or fruit. I haven't pruned it for almost a year, added a grow light to the window where it spends the winter. Any suggestions?

I am a little surprized nobody has answered this yet. I am not one of the experts here but I can attempt to answer your question with what I have learned from others here. A lemon tree grown from seed will typically start to fruit 5 to 7 years after it is planted in the ground in a normal citrus growing area provided it has not been pruned. Growing indoors or in a pot or in less than ideal environmental conditions can delay the time to fruiting but constant pruning will delay fruiting forever.

When a citrus tree starts to grow from seed, the first wood is immature and not capable of flowering. No matter how old the tree gets, the first part of the tree to grow will never become mature and never flower. Only mature parts of the tree can flower and produce fruit. Maturity at any given location on the tree is determined by the node count at that point and not the age of the tree. Nodes are any point where a leaf or thorn is or has been attached since the tree started to grow. Node count at a given point on the tree is measured by counting the number of nodes from that point to the root of the tree. It is not the total number of nodes on a tree. As a branch grows, more nodes are added to that branch until the mature node count is reached and further nodes added to that branch will be capable of flowering. Each branch of the tree has to meet its own mature node count before that branch can produce mature, flower capable nodes. Any branch that you prune before it reaches its mature node count will be set back by the number of nodes you just pruned from it and it will have to grow those nodes back plus any remaining nodes necessary to reach maturity before that branch will start to produce mature nodes.

If you look at a fruiting citrus tree that was grown from seed you will see that the fruit only grows in the top part of the tree because that is the only mature part of the tree. This is not unique to citrus. I have seen this on other types of trees.

Each citrus variety has a different mature node count. I don't know the mature node count for lemons. It's probably not an exact number. I do not know how much you have pruned from your lemon tree in the past either so it's hard to know how long you will have to wait without pruning before it starts to flower.

If you search for "node count" on this forum you will find additional information. Hopefully someone will correct me if I didn't answer your question correctly.

Jim, You may not be an expert, but you did pretty good at explaning that!

Thanks , Jrb , this is really new for me , because I was told to prune the tree exactly for flowering and fruiting ...
I've been told that for example : a seedling to be trimmed as it reaches 1 ft and after starting to branch , the newly formed branches to be cut as well to 1 ft size and so on until it's getting as I was told a 5-th grade branch node.

Now i have to reconsider all I knew about branching a citrus tree

danero, a citrus tree started from seed, must grow the required amount of nodes (different for each cultivar), before it becomes mature and begins to flower and fruit. Pruning, by it very nature, reduces the node count, and therefore delays the times for fruiting. With continued pruning, a citrus tree is prevented from ever fruiting, because the tree will never reach the required amount of nodes to become mature. - Millet (1,003-)

well 2 days now i have 2 meyers and 1 tahiti lime (beside my other citrus tree) and i was so curious how did they manage to flower beeing just 1 year old rooted cutting.



the leaves are clean now

A mature cutting, or bud, when taken from a mature tree, "remembers" their node count number and "remembers" that they are mature, so when rooted, or grafted, upon another tree, being mature they are capable of fruiting from day one. - Millet (1,003-)

let's see if i get it right

Taking a cutting from a citrus tree in flower will "remember" his status so it will produce flower and bear fruits right away.
ok then but when a couple of years ago i did a "back-up reserve" from a citrus mitis tree in flower it tooked 3 years to bear fruits.Was something wrong or just a branch not yet mature?

also thank you for taking the time to answer to my questions

Not knowing the tree, I can only guess. If the cutting, or bud, was from the portion of a branch with flowers, then they certainly were mature and capable of fruiting right away. NOTE: a seedling tree does not become mature in it entirety after it has grown the required number of nodes. Only the portion of the tree beginning at the required node count area, and above, is mature, and capable of fruiting. All of the tree below the required node count area remains juvenile for ever, and will never bloom and fruit. If the tree from which you took the "back-up reserve" was started from a seed, and the seedling tree had grown enough to become mature, but the cutting was taken from the lower immature portion of the tree, then the cutting would be immature, and would have to grow for some years until the node count was attained. - Millet (1,003-)

It was a calamondin tree , not from seed , and this must be it , i tooked it (maybe i didn't remember) from a lower branch , this might be the cause , and really I found out a lot of stuff tonight regarding citrus trees branching.
Does the GA3 has something to do with forcing a citrus tree to set flowers?
or is just a "polenizer" for a seedless fruit ?

thanks again