I have had a Kumquat tree for 5 or 6 years. It grow and now is 12 feet tall. But has never flowered. I feed it and care for it. It looks healthy but not flowers and certainly no fruit. This tree has 2 main trunks, it did have 3 could that have a bearing on my problem??? Thanks in advance for any help you can provide.
If the tree was grown from seed, it may not be old enough to produce flowers and fruit- citrus trees grown from seed vary in how fast they mature. If it was a grafted tree, it should be old enough now.
Check whether the tree is getting enough light and whether it's been fertilized appropriately. Kumquats especially need enough zinc.
This article lists other possibilities: