Bumps or growths on lemon tree - Garden

How old is the tree? Sometimes it takes several years before it begins to bloom. I have a potted Meyers Lemon that I move inside in the winter and outside in the summer. It didn't bloom for the first 5 years I had it and it finally did in the 6th season.

Hello, Colm -

This article from GardeningKnowHow.com may prove instructive:
https://www.gardeningknowhow.com/edible/fruits/lemons/lemon-tree-not-fruiting.htm

Best wishes.

Make sure that your Lemon Tree is well watered + fed with the appropriate food , when the flowers fall off they leave very small buds which may become the lemon, they take quite sometime to grow into lemons + because small you may think NO LEMONs - wait .

Just wait, sometimes it takes time for the lemon to grow. Take care, give time to time water and other necessaries to the plant.

You may get some help here

Lemon Diseases And Treatment Tips For Treating Lemon Diseases

To treat, remove all infected leaves and dropped fruit from the ground. Prune the lower branches from the tree, those that are more than 2 feet from the ground. Then spray with a fungicide such as Agri-Fos orCaptan. Botrytis fungus - Botrytis rot is yet anotherfungal infection which may afflict lemon trees.10 Jan 2016

Lemon Tree Problems: Treating Common Lemon Tree Diseases

https://www.gardeningknowhow.com/edible/.../lemons/common-lemon-tree-diseases.ht.. What is the Treatment for diseases of lemon trees Google Search

The insecticide that you want to use is called SAVIN.

That sounds like a fungus, take a leaf to a garden supplier, they should know.