Nice tree!!

how well does the soil drain. I would say that the size of the pot would be just fine for a year, my concern is that nursery soil, while good for temporary, is usually not good at all for long term. Have you pull out the roots and looked at them. If there is still room for them to grow you should be ok. Painting the pot a light color will help keep the roots from getting burned up in the hot sun.

OK I'll pull the whole thing and take a look. The soil seems to drain fine, water dripping out soon after I drenched it.
Thanks,

Suppose I want to repot it, is now a good time? What do you do with the soil that's in there now, should I rinse it off as much as possible (making the tree almost bare root)?
Thanks,

spring is always a good time to re-pot. I have done citrus in spring, early summer, late summer, fall. The key is to give it a week of rest in shade then gradually into filtered sun then full sun and extra water after you re-pot is good too.

if are planning to use one of AL's mixes or another soiless mix then the best thing you can do is try and remove all of the nursery mix as best as you can. Some people use a strong stream of water to blast out the existing soil and some people will use a bucket of water to help loosen the dirt. Citrus rebound well so dont be to afraid to get in there and dig out the old stuff.

If you aren't totally confident in citrus gardening using containers, I would suggest you leave it in the current mix until next spring. We have this privilege living directly in the citrus belt.

During the 1st year you learn watering, root temp protection, fert, and pests. More importantly, you learn a baseline behavior for a container citrus. Like what is normal and not for your tree.

Then when you repot completely into a new mix in a larger container, you have so many fewer issues to contend with.

Container trees are different than in-ground, I always suggest this to my family and friends when they purchase a fresh tree from a retail nursery.

I have a couple other citruses in containers since last year, and I've noticed that the soil stays wet too long. They're showing new growth now, but I think they should be showing more than what I'm seeing. I want to do it the "correct" way, now,with regards to the soil mix, rather than wait to see weak or no growth at a later time.