I currently have a bearss lime that is from Monrovia and was nicely planted in a 1 gallon container at the nursery. Water flows through very nicely.

I have owned the bush for about 1 year and I have kept it in the house in a south/west facing window (in Michigan). It's probably a few years old and was in this same container for about a year at the local retailer.

I'm concerned that it might be time to transfer to a larger container. The tree has been fairly stable and has had either bloom or fruit on it the entire time I've owned it, but for some reason, any new growth that appears just winds up shriveling instead of taking off.

How could I determine if it is the right time to re-pot into a larger container? Would you recommend using one of these rootmaker air pruners? Would this help the roots expand but limit crowding?

I'm hoping to be very careful. Any advise would be great

First thing to do is to look at your root. Take the pot off and look.
It would be a good idea to send a picture of the roots.

Normally, but not always, a tree needs to be transplanted every year, or root and foliage pruned and replace back into the same container. When you examine your tree's root structure as Sylvain has advised, I am sure you will see that the roots have long ago contacted the containers side walls and have begun circling around and around. - Millet (700-)

You guys are absolutely right about looking at the roots.

I checked it today, and just as Millet predicted, the roots have reached the edge of the pot and have begun wrapping around.

Check out this picture:

http://img714.imageshack.us/i/limebush006.jpg/

I don't really want to trim foliage - and although this bush isn't a dwarf, I would like it to grow a bit larger. I am thinking of transplanting into a 3 gallon container.

Please, any advise or step-by-step information that you could offer would be GREATLY appreciated.

Would it be appropriate to re-pot with CHC? Would Air Pruning pots be helpful at this point? Should I clear off the current potting mix off of the roots or just put this into a larger container?

Anyway, I LOVE this bush - greatest houseplant ever. Limes are AMAZING. Wanting to be very careful with a good friend.

**Clarification - this bush wasn't grafted onto "dwarf" rootstock - a detail that I failed to notice until after it was purchased.

Is it OK for me to continue to grow this as a container plant? Does this mean that I'll have to be more aggressive about root pruning and re-potting than with a dwarf? I want to make sure that I can strike a balance between letting the bush thrive and achieve new growth while maintinaing a reasonable size for my living room.

Regards!

Root Pruning Containers (RPC) are an excellent container. Had your tree been growing in a RPC the tree's root system would not be circling. Instead it would have developed a much fuller root system with many new side roots . You can transplant into a RPC at any time. Although, personally I much prefer CHC as a growing mix, the problem that your tree would now have with transplanting into CHC, is that the porosity of the two mediums would be vastly different. Therefore, at the interface the roots would tend not to grow into the CHC, plus when you water your tree, the water would take the path of least resistance, and just run down the less compact CHC, causing the original, more dense, medium to be dry. You could remove all of the old medium, so that the entire root system would be growing in a unified mixture, but by doing so, the chance of harming, or possibly killing, your tree would be very high. I would recommend when you transplant, use a well draining medium as close in texture as the original medium that the tree came with. There is an old saying which states, "A root grows as a bullet goes", meaning a root will continue to grow in the same direction until it hits a solid object causing it to deflect into a new direction. Therefore, when you transplant into the larger container, unless you CAREFULLY straighten out the ends of the curling roots, pointing them more or less toward the new medium, they will tend to just continue to curl around and around in there preset position. Lastly, when a container tree is not transplanted in a timely manner, and is left to grow in an undersized container, being root bound, the tree will begin to grow straight up, like tooth paste squeezed out of the tube. Such a tree develops a weak elongated trunk with very little foliage on top. The very best to you and this tree. - Millet (701-)

Thanks for the info. That makes sense.

My thinking at this point is to replicate the current medium (which has remained adequately porous) and to plant from a 1 gallon into a 2 gallon container of similar shape. This basically gives my root structure about 2 extra inches all the way around. I would assume that this should give me at least another year or 18 months in the new container.

Your comment promts a couple of questions:

-What are the possible impications if I simply plop this clump as-is into a similar medium and the roots just continue on their same trajectory (ie, without re-routing the roots or pruning them at all). None of the protruding roots have wound completely around, only perhaps a few inches. It seems like if there is more room, the trajectory would eventually make its way it to the other side of the pot and eventually through the newly created space

-Again, keeping the stability of an otherwise happy and healthy plant in mind, how much would you recommend manipulating the roots (either puning or moving) in such a case?

Thanks Again! After taking care of this plant for the last year, I really want to make it last for many years to come.

I also own a Tovita Orange tree that stands about 5 feet from the bottom of it's pot (5 gallon). I'll post a pic. It is probably due for a re-pot as well.

This is a Great hobby - I just sit in my living room watching limes and oranges grow while Michigan Winter is happening outside!

Even if you keep the same kind of medium you will have to straiten the roots. It is not difficult and there is no risk if you do it gently.
With a hose take off the outside part of the medium and then comb the roots with your fingers keeping under the water tap.
Choose a pot where you can put the plant with the the straitened roots. When repoting, use a nearly dry media and shake the pot to make the dirt go between the roots, then water.

I forgot to say that for at least one week (two is better) you must keep your plan out of the direct sun light and if possible in a wet place like 80 % humidity. this is to avoid imbalance between input and output of watter.