Putting it into a 15 gal pot is asking for trouble (death by root rot) unless you have a very well draining soil mix and know what you are doing. Go to a 5 gal pot instead. Use Foliage Pro 9-3-6 fertilizer because it has all micronutrients. Fish poop will not be necessary if you use FP 9-3-6. . Pruning will give you fewer fruit because fruit form at the ends of branches.

Hello RJ, welcome to the forum. Nice looking Eureka lemon tree. I noticed there is a tag on the side of the pot with a bar code, can you post a close up pic of that? It should say the type of root stock your tree is on. Most container folks here plant their trees in either a variation of 5-1-1 mix, which is a home made fast draining mix that you can do search for the recipe here on the forum. Another growing medium some folks use is a gritty mix which is a soil less type of mix and somewhat like hydroponics as you will almost have to water it daily in a warm dry climate during hotter months of the year. As Vladimir stated above foliage pro is used as a good all around fertilizer to help with sustaining good growth and flowering in the spring. As for pruning your tree, not much pruning is needed unless you get some aggressive growth that you want to trim back or keep your tree to a certain shape. What area of the world do you live in? The store tag looks like the tree came from Lowes and you stated it’s a semi Dwarf so I’m going to take a guess that your tree is on C35 root stock. What is your grow zone?

Evan

I live in Dana Point Southern California 1hr30 South of LA 1hr30 north of SD...it is summer all year round here. Not sure which zone that is

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