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Key Lime Tree

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Backyard Key Lime Tree

Key lime tree in my winter garden

Key lime tree in my winter garden

How to Grow a Key Lime Tree

Key lime trees are a lovely addition to the backyard garden, best in USDA zones 9-11. In other parts of the country, it can be potted up as a container plant and brought indoors during cooler months. The Key lime fruit is small and round, and turns yellow when fully ripe. Key limes are the main ingredient in Key Lime Pie.

The "key" things to remember when planting and growing a Key lime include:

  • Key lime trees are shallow-rooted. It's important to keep this in mind when spreading mulch or fertilizer so as not to suffocate or burn the roots.
  • Key lime trees are heavy feeders. Like other citrus trees, Key limes produce best when fertilized regularly and in sufficient amounts.
  • Key limes like well-drained, slightly acidic soil. They don't produce well if their soil is soggy or too cold, and they don't do well in alkaline soil.

Planting Instructions

Before you plant, check to make sure that the place you selected is well-draining by digging a hole about two feet deep and filling it with water. If the water does not drain well, if it stands for some length of time, consider picking a different spot. If you have no choice, amend the soil well with vermiculite and peat moss, plant it on a mound, or consider planting in a pot and keeping your Key lime on the patio.

Choose an area that gets full sun all day and is protected from wind.

Step 1: Dig a hole that is about twice as wide and twice as deep as the root ball of the tree.

Step 2: Amend the soil in the planting hole with peat moss and vermiculite to aid in drainage, and amend the back-fill soil as well. If you are planting between March and September, add slow-release high nitrogen fertilizer to the soil as well as Ironite, or other iron-containing amendment.

Step 3: Open up the root ball slightly, trimming away any obviously tangled roots so that the plant does not strangle itself. Place the root ball into the planting hole

Step 4: Backfill to the same soil line on the tree as it was in its original pot, that is, don't plant the tree any deeper than it was previously, and don't plant it any higher than it was previously. Note: This is still true even if you plant the tree on a mound.

Step 5: Press the soil firmly, but don't pack it tightly. Remember to protect the roots. Build up a soil berm to create a watering ring around the tree, following the leafline, or about 3" in diameter (depending on the size of the tree.)

Step 6: Water in well.

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Key Lime Fruit

Key lime fruit has a yellow skin when ripe. The fruit is smaller than a regular lime, and seedy.

Key lime fruit has a yellow skin when ripe. The fruit is smaller than a regular lime, and seedy.

Key Lime Tree Care

  • Once planted, your Key lime tree will need regular high-nitrogen fertilizer and regular watering. Take care not to over water! Feed between March and September.
  • If you live in an area with alkaline water, spread used coffee grounds around the tree regularly, digging them into the top inch of soil Alternatively, amend regularly with Ironite.
  • Key lime trees seem to be prone to growing suckers, which grow straight up from the center of the tree. Prune them flush to the branch.
  • Mulch around the tree in summer months using dried leaves, cocoa mulch, peat moss, or other lightweight mulch. Note: Cocoa mulch is not recommended if you have dogs. If you use wood chips or other "green" mulch, be aware that it will take nitrogen away from the soil as it decomposes. Spread some slow release nitrogen rich fertilizer like Miracle-Gro under wood chips mulch so that the tree is not robbed of nitrogen.

Snail Care

In Southern California, Key lime trees will flower throughout most of the year. The buds in winter will be small and tight and appeal to snails. It is important to pick off the snails from the tree, as they will voraciously devore every bud in very little time.

To protect the tree from snails, try copper tape around the base of the tree. Wind the tape in a spiral - not directly across like a rubber band - to give the tree some growing room.

Key Lime Tree Flowers

Key lime tree has small white flowers with an intoxicating scent.

Key lime tree has small white flowers with an intoxicating scent.

Copper Tape For Snails

Copper tape is a good snail deterrent

Copper tape is a good snail deterrent

Wrap copper tape in a spiral around tree trunk.

Wrap copper tape in a spiral around tree trunk.

Key Lime Tree Growing Tips

  • In colder months, Key lime trees may drop all of its leaves, or have its leaves and flowers eaten by snails. The best thing is to protect it from snails and mulch around the tree, then wait for warmer weather which will bring new growth.
  • Be patient! Key lime trees produce best and more consistently after 3-5 years.
  • If rats or other garden critters start eating your limes, try covering the fruit with used sheer nylon stockings. (Put your feet in them for a couple hours and then put around the fruit. Just wash the fruit before eating.)
  • Yellow leaves may mean a lack of iron or too much water. If you're not overwatering, try giving the tree some Ironite.
  • Remember that the fruit is fully ripe when the skin is yellow. The fruit can stay on the tree for many months, so it is best to leave it on the tree to ripen and not pick it early.


KA Hanna (author) from America's Finest City on February 11, 2013:

Thanks Dreamhowl! I do love my little garden, it's a lot of fun to see what I can get to grow!

Jessica Peri from United States on February 11, 2013:

I love how you have such a diverse garden, and the pictures are fantastic as well. I would never have guessed that copper tape was a snail deterrent. Voted up!

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