Key Lime Tree: Develop Your Personal Cake

What do you think of first when you hear the words "key lime"? We suspect delicious cakes have jumped into your head or maybe even an alcoholic drink. If you ask us, we only have eyes for the key linden tree. After we are done with this, this tree will surely catch your attention.

The key linden is a vigorous tropical plant that produces all year round. They are rinsed with citrus fruits in early summer and late autumn and get a small but steady harvest for the rest of the year. In addition, you can enjoy the lush green of the tree and the fragrant flowers.

And let's not forget the delicious fruits! Key Limes are normal miniature limes – about the size of a golf ball. They have a thinner skin and a stronger taste than normal limes, which more than makes up for the size. Just like classic limes, they are usually picked before they are ripe. If they stay on the branch, they will eventually turn into yellow limes!

So let's dive into the care of this culinary tree. This post is sponsored by Fast growing trees, a source of quality for important linden trees and many other species.

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Brief instructions on care

Common names Mexican lime, bartender lime, West Indian lime
Scientific name Citrus aurantifolia Swingle
Harvest month (s) Summer (June to August)
light Full sun
water When the floor starts to dry
ground Well drained, nutritious
fertilizer High nitrogen content 3-4 times a year
pests Snow scale, citricola scale, mites
Diseases Citrus Crab, Phytophthora, Brown Fruit Spot

Everything about the Key Lime Tree

The classification of citrus trees has long been controversial among taxonomists. The most popular belief is that the main linden trees are a mix of papeda and citron limes. It comes from Southeast Asia and is said to have traveled through the Middle East, North Africa, Spain, the West Indies and finally its namesake, the Florida Keys (a small chain of islands off Florida). Citrus aurantifolia is currently grown commercially in many of these areas except Florida.

If you live in the tropics or zones 9-11, you're in luck – this tree thrives outdoors. For you northerners, dwarf trees are available for indoor cultivation (look for Citrus aurantifolia "Mexican Thornless").

Important linden trees developed thorns as a defense mechanism against animals – and apparently against gardeners. Always wear heavy, elbow-length gloves when working with this plant. As already mentioned, the dwarf tree is thornless, as are other varieties. These trees occupy 6-13 feet of vertical space.

Plant key limes

Citrus aurantifolia flowerCitrus aurantifolia is wonderful when it blooms. Source: dogtooth77

To prepare a lime cake from scratch, you first need to plant a tree. Here's what you need to know to plant your future cake!

When to plant

You can plant your tree at any time of year, but we recommend late winter. This gives the tree time to settle in its new home before the busy growing season in spring. When planting in an indoor / outdoor container, do so at the beginning of the warm or cold season so that no locations need to be moved while you are still settling.

Where to plant

Choose a place where the sun shines for about 10 hours a day. It must also be protected from cold winds; If you plant it on the south side of your house, the north breeze will be blocked.

Ideally, these trees should be 25 feet apart. Place yours at least 4 to 6 feet away from the competition. Leave space for easy harvesting and trimming.

Bring the tree in if you live in an area that is consistently below 50 ° F in winter. Use a container that is slightly larger than the root ball (you may need to enlarge it later). Do not use too large, otherwise too much moisture will be trapped.

How to plant

Regardless of whether you bought a baby tree or grew one from seeds, we recommend planting it. First, dig a hole that is as deep as the root ball and twice as wide. Mix some organic compost into the backfill as your tree will get hungry!

Carefully push the tree out of the container and brush away any loose soil. Massage the root ball gently so that the roots can spread. Now just put it in the hole and add the treated backfill base. Tap the bottom lightly to remove any air pockets.

Finally, and above all, add the choice of your mulch to the surface. Spread a few inches around the tree and avoid the trunk. This binds the necessary moisture and produces additional nutrients. Refill the mulch over time as needed.

Water your newly planted tree frequently until it has established itself. You can expect flowers and fruits in 2-3 years.

Key Lime Tree Care

Baby lime on treeA newly formed lime on the top of a branch. Source: Brixton

Now that the difficult part is no longer in the way, everything is low-maintenance and low-fertilizer until harvest. Here's what you need to know:

Sun and temperature

As already mentioned, Mexican linden trees need 10 hours of sun. They tolerate some shade, but need a lot of light for healthy fruit formation. If your plant lives indoors, bring it out in summer. Hold it inside through a south-facing window for optimal light.

Keep in mind that these are tropical plants that need tropical warmth. Keep your plant at temperatures between 60 and 80 ° F. In extreme heat, give your tree some shade in the full sun to protect it. When the temperature drops below 50 ° F, bring your linden tree inside.

Water & moisture

Citrus aurantiifolia can be a little picky about the water, so you need a consistent schedule. When the soil starts to dry out, pour it deep. If it's in a container, do so until the water comes out of the drain holes. Depending on the temperature and humidity, water about 1-2 times a week. Young limes need more water than ripe ones. In the first 1-2 years of its life, you need to water your tree at least twice a week.

Watch carefully for signs of over and under water. When overwashed, the leaves turn yellow and the risk of bacterial and fungal growth increases. Underwater leads to dry, curled leaves.

Keep your tree lively with high humidity. When growing an indoor linden tree, you can use a humidifier to make him happy. Keep the tree away from heating ducts as they dry out the air.


Choose a well-drained soil that is loamy or sandy (look for special citrus tree floors). The pH must be slightly acidic (5.5-6.5) and contain plenty of nutrients. Work with compost or animal manure so your tree can feast after planting.

When pouring, watch the floor to make sure it drains well enough. There should be no water on top or take more than a week to dry out.


Because you add organic fertilizer when planting the tree, you can hold back the supplements until they're firm and half a foot taller. Then apply a granular fertilizer 3-4 times a year. A balanced fertilizer is good for young, non-bearing trees. However, once they have matured, use a fertilizer that is rich in nitrogen and potash. When your key linden tree has lost its strength, add a trace element with calcium, zinc, iron and manganese.


Lime fruit and branchesThe branches of the key linden trees can bear a surprising number of fruits. Source: JHochstat

Prune your lime at the end of autumn or early spring. This offers plenty of room for new growth during the growing season. Regardless of whether you are growing a full-size linden tree or a dwarf key linden tree, it must be pruned properly.

When trimming, always use clean, sharp hair clippers and heavy gloves to protect yourself from thorns. First, find and remove any dead, dying, or sick branches. From there you can reduce the size, cut awkwardly shaped branches and thin the middle. Aim for a uniform shape that allows good air circulation and future growth. However, do not remove more than a third of the branches at the same time.


Although it is a hybrid, important linden trees grow well from seeds. Which is better, you can start it any time of the year. Take the seeds from a fresh, healthy lime or order them from a trusted seed nursery.

There are two main methods of germinating lime seeds. The first is to soak them in warm water and then fold them in a damp paper towel. Put the towel in a sealed plastic bag and put it in a warm, dark place like a closet. Give the seeds to germinate for about a week. Then you can plant them ¼ inch deep in moist soil in a 1 gallon container.

The second method is to plant the seeds ½ inch deep in a small container (approximately 4 inches deep). Place the container on a heating mat and cover it with a transparent lid, e.g. B. plastic film with some holes. Spray the floor daily with a spray bottle. Remove the heating mat when the seedlings protrude from the ground and place them in the sun. If they are a few inches tall, transplant them to their permanent home.

Regardless of the method, you can now keep the seedlings in the sun with moist soil. It is important to protect them from direct heat and frost when they are young. Fertilize them every two months until they are well established and actively growing. It will take about 5 years for the seedlings to become lime producers.

Air layers are a less common but possible method for important linden trees. It's about making a cut in a branch and wrapping it in peat moss and plastic. Over time, roots sprout from the cut and feed on peat moss. The branch is then cut from the tree and planted in the ground. For more detailed air stratification instructions, see this article.

Harvest and store key limes

Key LimesFully ripe limes have a yellowish color. Source: Stacy Spensley

Cake makers are happy! After all this hard work, it's time to harvest the key lime and use it wisely.


Although limes are yellow when fully ripe, they are usually picked green. Wait for the fruits to turn pale yellow-green before hand picking them. The lime is the size of a golf ball and gives way slightly when pressed. Since it is not fully ripe, you may need to cut the stem to avoid damaging the branch. A yellow lime falls from the tree and should be collected from the ground.


It may be tempting to display your home-grown limes, but they are better stored in the refrigerator than on the counter. They stay in the sharper drawer of the fridge for about 1-2 weeks. If you really want to extend your life, seal it in a plastic bag before cooling. They can take a month or more – that's enough time to make a lime cake!

Sliced ​​lime usually lasts 5-7 days in the refrigerator. When storing multiples, look for those that spoil or become moldy and dispose of them immediately so that they do not contaminate the others. Lime juice can be frozen for up to 4 months.


Key Lime PieMmmm, lime cake. Source: brenbot

As a good gardener, you should always be on the lookout for growing problems, pests and diseases. Catching them early can be a matter of life and death.

Growing problems

Trees that produce healthy flowers but no fruits are most likely needed pollinators, For indoor trees and areas with small bee populations, you have to do the work yourself. Simply swing a clean brush into the center of a flower and transfer the pollen to another flower.

Yellowed leaves are usually a sign that the key lime is over-watered or needs more fertilizer. First check the soil drainage. If it's soaking wet or collecting puddles, you need to mix in some sand or pearlite. Stop pouring again until the soil begins to dry out. If the soil and water levels are okay, try adding more fertilizer.


Citrus snow scale, also known as white louse, is an aphid-like insect that damages the trunk and branches. In large numbers, it makes the tree look as if it has been dusted with snow. Parasitic wasps such as Aphytis lingnanensis and Aphytis gordonae are commonly introduced to control the population of snow scales. Horticultural oils also eliminate these pests.

A serious threat to Key Limes, Citricola scale reduces fruit size and overall yield. These little pests suck out the juice and leave honeydew that attracts black soot mold. The mold then inhibits photosynthesis, which leads to damage to fruit production. Insecticide is the best recommendation for dealing with these pests, especially bio petroleum spray. Biological controls are also effective by introducing predators such as Metaphycus and Coccophagus.

citrus mites represent the greatest threat to young trees. In large numbers, they look for sap and cause deformed fruit and a silvery color to the leaves. Prevent these mites by removing dead branches, leaves and other debris. Existing populations can be controlled with miticide spray or neem oil.


If your key lime is constantly in warm, humid weather, it may be susceptible to citrus canker, This fungal growth occurs in dark spots that spread across the leaves and branches. Ultimately, it will cause the leaves to die and fruit to drip. Prevent this by keeping the leaves dry while watering them. To stop the disease, apply a copper fungicide.

Phytophthora is a soil fungus that can cause gummosis and or root rot, Gummosis penetrates the bark, causing it to crack and seep. Root rot leads to rotten roots, yellowed leaves and stunted growth. To prevent the fungus from spreading, not over water. If you know that Phytophthora is in the ground before planting, first fumigate it with Metam sodium. Gum can be cured by removing infected bark and treating the rest with copper fungicide.

Brown fruit rot attacks your precious limes with brown spots. From there, the stains consume the whole fruit and mummify it. The flowers can also be hit from these places, causing them to die and spread the disease to the surrounding branches. Brown rot does not kill the most important linden trees, but drastically reduces fruit yield. If you see these spots, immediately remove the affected areas and burn or bury them. If the disease persists, apply a copper fungicide.

frequently asked Questions

Q: How high will an important linden tree be?

A: Key linden trees are approximately 6-13 feet high. If that's too big for you, there are dwarf varieties that only grow 2 to 6 feet tall. Look for these varieties in a kindergarten.

Q: What is the difference between a lime and a key lime?

A: Key Limes are much smaller, have a thinner shell and are more acidic. They have a stronger taste than normal limes, which is why they are often used in recipes and drinks.

Q: Where do Key Limes come from?

A: Key Limes are originally from Southeast Asia. They have traveled the world to get to the Florida Keys, their namesake.

The green thumbs behind this article:
Rachel Garcia
Juicy fanatic
Lorin Nielsen
Lifetime gardener

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