I have two Cassia Fistulas (Amaltas / golden rain tree / canafistula) in my garden outdoor, planted 5 feet apart. They are 5 years old. The main trunks are of about 8\" diameter, and 12\' tall having been pruned repeatedly. Both have never flowered ever. Could you please advise what could be the reason, and suggest a remedy? Thank you, Regards Bejoy
Cassia Fistula Blooming
Certified GKH Gardening Expert
My research showed that some take up to 6 to 8 years to bloom.
Avoid pruning out any upward growth on the tree, this is the first branches to flowers.
Make sure you are not fertilizing, Too much nitrogen will inhibit flowers. Even lawn fertilizer near the tree could be effecting the tree.
Here is a link with more information.
You can also check with your County Extension Office and inquire at the age most Golden Raintree are blooming in your region.