How To Care For Your Key Lime Bonsai Tree

About The Key Lime Bonsai Tree

The key lime, or acid lime, is a mildly acidic citrus fruit originating in southeast Asia. It has been cultivated across the tropics of the world, including the Florida Keys - where it gets its name.

The tree is characterized by its shiny evergreen leaves, the wing-like appendages on the leaf stalks, and its incredibly fragrant white flowers.

The flower and fruit often will appear at the same time, making it a true show stopper.

The key lime is easy to care for, and its tasty fruit can be used in a drink, or as a snack, or in the famous key lime pie.

Placement

Like most citrus trees, a key lime bonsai is tropical.  That means it wants to stay warm all year long.

When the outdoor lows are around 50 degrees F, place your key lime bonsai tree on a windowsill indoors.  South facing is best, east or west is second best, and you should avoid north if you can (or just use an indoor grow light.)

When the temperatures are above 50 degrees, your key lime bonsai tree can live outdoors.

It loves a TON of sun, so don't feel the need to protect it.  Just ensure it's well watered.

Watering

Never let the soil completely dry out.  Whenever the soil seems dry, thoroughly water your tree until the water runs clear from the bottom.  In the growing season, this can be daily. 

If you need help, a good moisture meter will guide you.

Humidity

When your key lime bonsai tree inside, using a humidity tray is recommended.  It will prevent the water from running on the floor, and can help boost the humidity around the tree.

Fertilizing

Since your key lime bonsai is in a small pot, and not the ground, it needs nutrients.  A slow release (pellet based) fertilizer is perfect for this, and can be added sparingly every 1-2 months during the growing season.

If you plan on eating the limes, you should stick with a fertilizer that you're comfortable putting on a food producing plant, but dilute it to at least half the recommended strength.

Pruning & Trimming 

Trim back the new growth to the farthest safe point that looks good to you — but never remove all of the new growth.

A regular trim will help keep your citrus key lime bonsai tree short, while helping the trunk grow thicker.

Repotting

Repotting must be performed periodically on your bonsai, Key Lime Citrus included, when its root system has filled the pot.  If you can clearly see the roots coming out of the bottom of the pot, it’s time to repot your bonsai.

Generally, this means every 2-3 years for a deciduous tree and every 4-5 years for an evergreen or tropical.

Repotting should be done in mid-summer, when the tree is at it’s least fragile state.

The key lime bonsai tree, along with all of its soil, should be removed from the pot.  From there, you can trim away no more than 1/3rd of the root mass (1/4th is preferred.) 

Then you can repot the tree in the same pot, or give it a newer / bigger pot to thrive in.

After repotting, your key lime bonsai should be thoroughly watered.

Diseases, Insects & Other Pests

Your key lime bonsai can be treated for pests like a normal key lime tree.  Just remember, your tree is miniature and will need a much smaller and more gentile dose of treatment.