Even in hot Austin, our winters get too cold to leave lime trees outdoors when temperatures dip, so I’m growing both Mexican lime, Citrus aurantifolia, and Kaffir lime, Citrus x hystrix, in containers.   Then I can move them indoors when necessary.  Mexican limes are also known as key limes.  Kaffir limes, or makrut, are grown primarily for their leaves, which are used to flavor Lao and other Southeast Asian dishes.

I picked up both of these plants earlier this year, and this evening, after the sun goes down, I’ll re-pot both into larger containers.

Mexican Lime waiting to be re-potted.

Limes need to be well drained, so I have added a couple of inches of expanded shale to the bottom of each container.

Expanded shale in bottom of container for drainage.

At the same time, given that our temperatures have already reached the upper nineties in Austin, I have to water these almost daily.  If you are growing these in another region, check the pots before watering and don’t water until the soil is slightly dry.

The frequent watering can flush out soil nutrients, so I’m also fertilizing every two weeks.  I use a mix of seaweed and liquid fish diluted in water.  Currently, I’m using a commercial mix made by Lady Bug Brand that also includes small amounts of magnesium sulfate, ferrous sulfate and zinc sulfate.  Citrus can develop chlorosis from a lack of any of these.

Kaffir lime leaf

Key limes, almost ready to harvest.

Both of these limes will be transplanted to an even larger container in a year or two.  After that, I may need to occasionally root prune them to keep them happy in a container of a manageable size.  I’ve already been enjoying my summertime treat: sparkling water with a twist of lime.