We could answer better with some pics of the trees further back to see it full size.
However, I'd be inclined to leave an 18" tree alone and not prune. Citrus are often somewhat awkwardly shaped when young, but they will outgrow that in time. And they need all their leaves and branches at that age to make enough energy to grow more.

It will also make a bit of a difference as to whether you'll be keeping it in a container or planting it into the ground. In zone 10 it could grow outside. An in-ground citrus will grow much faster and could handle a little pruning sooner. But the pruning will only be for shaping, citrus don't need pruning to fruit well, you don't really HAVE to prune ever.

All good points I should have addressed. Currently I'm a renter, so all of my plants are in pots. I wouldn't mind a little pruning to keep size in check but I don't want to sacrifice blooms/fruit maturity to do so. (I've read that keeping them small can sometimes delay fruiting) I'll be keeping it in vase shaped pots for ease of transplanting when it's time.

It's not terribly awkward right now but wasn't sure if it would lead to trunk weakness down the road with a crotch so low.

I'll grab a picture of it, full size in a few minutes.

Thanks. Kristiina

The black hand points to the branching I'd like to keep. The smaller two white hands are pointing to the lower branches while the big white hand points to where they originate. My daughter as a size reference...she's 3.

Do you know what type it is? Being a seedling I wouldnt do any pruning that wasnt absolutely needed. However if you leave it be it might be a bit unbalanced. if that is a concern to you then prune the white hand portion off and let it grow more upright.

Personally I wouldnt do anything but treat it well and let it grow. It looks very green and healthy so good job on that!

Thanks. It really like the repot I gave it a few months back. I don't know the variety. I was guessing lemon but I suppose it could be anything.

Thanks for the help. Kristiina

You can break a leaf and smell it. Most all lemons will smell like lemon and limes the same. My orange tree leaves dont really smell like oranges.

Good to know mksmth! I'll try that when I get home!

Kristiina

Whoa! Mksmth, if this holds true, it's a very cool trick! It smells very strongly of lime with a distinct sweetness. Any ideas what kinds of limes have thorns like this? Tops is upper branch while bottom is lower. That's my pinky finger for reference.

I would not prune the lower branches. I would break any buds off that start to grow. When the leave are used up in a year they will fall off and the branch will die. As the branch and leaves die they will release any nutrients back to the tree to be recycled.

Steve

Cool. Thanks Steve. That's a good way to give back to the tree.

Kristiina

Most limes have thorns, but the Mexican, aka Key or bartender's, lime has the most and largest thorns. Plus it comes true from seed. And if it is a key lime, you're in luck as those take pretty much the least amount of time to mature to fruiting from seed grown. Like maybe 4-6 years or less.
Looks pretty healthy so far, good job!

Woo-Hoo! I'm doing a happy dance!

Thanks everyone for the input!