Gardening Recipes

How to grow and use makrut limes (Citrus hystrix)

How to grow and use makrut limes (Citrus hystrix) thumbnail
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Last Updated on February 25, 2024 by Aaron von Frank

We’ve grown makrut limes (Citrus hystrix) for over a decade in our non-tropical Zone 7b ag zone. In this article, you’ll find out how to grow and use all edible parts of this amazing citrus, from leaf to flower to fruit!


I. Kaffir lime vs makrut lime vs Thai lime – same or different?

Let’s start with the name, which comes with controversy…

First, the plant’s scientific name is Citrus hystrix. Hystrix is a genus of porcupines; the scientific name is owing to the fact that these citrus plants are indeed thorny, although not nearly as thorny as other citrus varieties we grow. 

Citrus thorns compared, from left to right: makrut lime, Buddha's hand, Yuzu. Our makrut tree's thorns are quite tame by comparison. This may be due to breeding work that has helped tame the thorns relative to the older genetics.

Citrus thorns compared, from left to right: makrut lime, Buddha’s hand, Yuzu. Our makrut tree’s thorns are quite tame by comparison. This may be due to breeding work that has reduced the thorns relative to the older genetics.

However, like many popular plants, Citrus hystrix also carries multiple common names, including:

  • makrut lime, 
  • Mauritius papeda,
  • Thai lime, and 
  • kaffir lime.

The common name “kaffir” lime (which also happens to be the most frequently used name in the western hemisphere) is the name that has elicited controversy…     

Is “kaffir” lime an offensive or racist name?

Depending on your country of origin, the word kaffir can be as offensive to some people as the n-word is in America. In fact, the word “kaffir” in South Africa carries with it a similar awful history and meaning as the n-word.

However, as best as food historians and linguists can tell, the word “kaffir lime” did not actually start off with the intention of being a racist slur or a disparaging name for the fruit. Instead, its etymology is most likely owing to two alternative factors:

1. To Indian Muslims, the word “kafir” meant infidel, the term used to describe non-Muslims. Since these limes were imported from non-Muslim areas of southeast Asia, they were called kafir limes by Muslims in that region. (Later spelled kaffir with two f’s, by Europeans.)

2. The Kaffirs are an Afro-Sri Lankan ethnic group who still live in Sri Lanka (formerly known as Ceylon). Sri Lanka is one of the locations where Citrus hystrix has a long history of use — and possibly where the plant originated.

In 1888 in The Cultivated Oranges, Lemons Etc. of India and Ceylon, author Emanuel Bonavia excitedly describes the fruit of this citrus, thinking it might be the plant from which all other limes originated. 

On pages 82-83, Bonavia also notes, “In Ceylon [Sri Lanka], this Citrus is called lima, or kudalu dehi (leech-lime), and also Caffre-lime, by the Europeans.” (For reference, caffre is an alternate spelling of kaffir.) Since this book was written in 1888, it represents the earliest known English-language reference to caffre or kaffir limes, and was not used as a pejorative term.

Makrut lime (Citrus hystrix) leaves and fruit on our tree in Greenville, SC. We always get a bit of a thrill knowing about the history of the plants we grow and what an interesting journey they've been on before we came into possession of them.

Makrut lime leaves and fruit on our tree in Greenville, SC. We always get a bit of a thrill knowing about the history of the plants we grow and what an interesting journey they’ve been on before we came into possession of them.

Nevertheless, around this same time period in South Africa, the words caffre and kaffir were both being used as a racist term by European colonialists to characterize the region’s Black majority. So, it’s certainly understandable how someone in South Africa could find the name “kaffir lime” highly offensive, given their history.

Our vote? When using a common name for Citrus hystrix, we simply call them makrut limes or Thai limes. Thus, in this article, we’ll refer to them as makrut limes moving forward.

II. How to use makrut limes

Although the leaves of makrut limes are the best known part of the plant for culinary purposes, the flower petals and fruit are both edible and uniquely wonderful. Here’s how to use the edible parts of a makrut lime tree:

1. How to use makrut lime leaves

Here you can see mature makrut lime tree leaves (like the one in my hand) as well as the immature, purple leaves just starting to form. The mature leaves are tough, with a similar texture to bay leaves. The immature leaves also pack lots of flavor and are very tender.

Here you can see mature makrut lime tree leaves (like the one in my hand) as well as the immature, purple leaves just starting to form. The mature leaves are tough, with a similar texture to bay leaves. The immature leaves also pack lots of flavor and are very tender. 

Makrut lime leaves taste very unique with bright notes of lime and other citrus. The leaves are used as a flavoring in many Southeast Asian cuisines, somewhat akin to the way bay leaves are used here in America.

You can harvest makrut lime leaves year round since the trees are evergreen (like all citrus). However, we think the best time to harvest the leaves is in summer when the new leaves have reached maturity and are vibrant, shiny green.

To release the most flavor quickly, the leaves can be crushed by hand or chopped prior to adding them to a dish. You don’t actually eat the leaves, they just flavor the dish. The leaves can either be removed prior to plating or moved aside during a meal.

Here’s how you can use makrut lime leaves: 

Savory – A great way to use makrut lime leaves on the savory side of things is Thai tom kha gai soup, which we make any time we have a nice haul of maitake mushrooms. 

You can also add makrut lime leaves to a pot of cooking rice to infuse it with unique flavor. 

Sweet – On the sweet/dessert end of the spectrum, try our Makrut lime leaf coconut kuzu pudding recipe (sweetened with honey). 

Drinks – You can chop and use makrut lime leaves to make a flavorful tea. They can also easily be made into a simple syrup with sugar and water, then used to flavor cocktails.  

2. How to use makrut lime flower petals

The four to five-petalled white flowers of makrut limes are highly fragrant and make an excellent edible flower as well. To harvest, you can remove the mature flower petals (or let them drop) without reducing fruit set.

The four to five-petalled white flowers of makrut limes are highly fragrant and make an excellent edible flower as well. To harvest, you can remove the mature flower petals (or let them drop) without reducing fruit set.

Yes, citrus flower petals (including makrut lime flowers) are edible and make wonderful teas. You can put a sheet down under your citrus plants and gather the fallen flower petals without affecting fruit set. 

Read: How to grow and make lemon blossom (or other citrus) tea.

Of the dozen citrus varieties we grow, makrut lime flower petals are our favorite. They have a wonderful soft texture and excellent flavor. In addition to using them in teas, they also make a good garnish on sweet and savory dishes alike.

When do makrut lime trees flower? In late winter through early spring.  

3. How to use makrut lime fruit

The brain-like fruits of makrut limes are intensely flavorful. You can pick them green or let them ripen to the point that they start to turn dull green-yellow and fall off the tree. The skins continue to turn more yellow as they ripen after picking indoors.

The brain-like fruits of makrut limes are intensely flavorful. You can pick them green or let them ripen to the point that they start to turn dull green-yellow and fall off the tree. The skins continue to turn more yellow as they ripen after picking.

We originally got our makrut lime tree for its flavorful leaves. We were pleasantly surprised to discover that we loved its edible flowers and fruit as well.

Makrut lime fruit ripens in winter. Our tree produces mature fruit from November through February.

Makrut lime fruits are small (about 2-3″ in diameter) and visually unique. The skin is highly wrinkled, giving the fruit the external appearance of a miniature green brain.

When ripe, makrut lime skins turn from green to dull green-yellow, eventually falling off the plant. Each fruit can be juiced and the skins can also be used as a flavoring.

Does makrut lime fruit taste different than regular limes aka Persian limes (Citrus ×latifolia)? Yes! Makrut limes are far more potent and intensely flavored than regular limes.

We juice our makrut limes to use in limeade and savory Asian dishes. Be aware that a little makrut lime juice or skin can add a LOT of intense flavor to whatever you’re using them in.

A special day for us: we were able to get home-grown papaya and makrut limes at the same time! Makrut lime juice is far more intense than regular lime juice but still quite good on papaya.

A special day for us: we were able to get home-grown papaya and makrut limes at the same time! Makrut lime juice is far more intense than regular lime juice but still quite good on papaya.

We’ve read that makrut fruits are often candied in Southeast Asia, but have yet to attempt this ourselves. I did try to make a makrut lime juice curd that tasted more like a household cleaner than a dessert.

After harvest, fully ripened makrut limes will last about 10-14 days indoors at room temperature. Or you can store them in a ziplock bag in your refrigerator veggie drawer for 3-4 weeks. 

III. How to grow makrut limes

First thing to know when considering growing makrut limes: unless you live in ag zone 9 or higher, don’t plant them in-ground or they won’t make it through the winter. While some sources say makrut lime trees can survive a light freeze, we wouldn’t risk it.   

Can you grow makrut lime trees in a pot?

Yes, you can grow makrut lime trees in a pot, but we’d recommend dwarf or semi-dwarf trees for best results. If you don’t live in a very warm climate region (zones 9+), growing makrut limes in a pot is your only option, assuming you don’t have a heated or solar passive greenhouse.

Our makrut lime tree growing in a large pot in Greenville, SC.

Our makrut lime tree growing in a large pot in Greenville, SC.

We live on the outskirts of Greenville, SC in Ag Zone 7b. Nope, not the tropics.

As such, we grow our 10+ year old makrut lime tree (and other citrus) in a large pot. We use our specialized pot moving device to bring it into a heated garage during our frequent sub-freezing winter temperatures.

We have left our makrut tree outside when temperatures dipped into the low 40s/upper 30s °F (about 4°C) and it did fine. However, we doubt it would do fine if forced to endure sustained cold temperatures in that range.

Are makrut lime trees self-fertile, e.g. self-pollinating? 

Yes, makrut lime trees are self-fertile. This means you only need one makrut lime tree to get fruit.

However, if you’re growing a makrut lime tree indoors or in a spot where pollinators can’t access the flowers, you’ll want to use a q-tip or small paint brush to pollinate the flowers by hand.  

How big are makrut lime trees?

Standard makrut lime trees grown in-ground can reach heights of up to 25′ with a 12″ width. However, dwarf of semi-dwarf cultivars grown in pots can easily be kept pruned to 3-5′ tall x 3-4′ wide. 

Where can you buy makrut lime trees?

If you can’t get makrut lime trees at a local plant nursery, you can buy them through online nurseries such as Thai Greenhouse

As with all citrus trees, there are legal restrictions on shipping to certain states. These laws are intended to prevent or slow the spread of citrus greening, a disease that is devastating citrus trees and citrus farms in the US and around the world. 

How do you care for a makrut lime tree? 

Below is the basic information you need to know to care for a makrut lime tree:

Sun 

Makrut lime trees prefer full sun spots, 6+ hours of direct sunlight per day. They can tolerate lower light levels for short timespans, but will grow and produce best in full sun.  

If you want lots of fruit and leaf production, make sure your makrut lime tree is in full sun.

If you want lots of fruit and leaf production, make sure your makrut lime tree is in full sun.

When growing makruts in pots in cooler climate zones, you will likely have to bring them inside for months at a time. If so, make sure they’re placed in a sunny, south-facing window, under a high quality grow light, in a sunroom, or similar setup.

We roll our citrus (including our makrut tree) into a heated garage any time temperatures dip into the upper-30s or below.  

Soil

If growing makrut lime trees in-ground, they prefer nutrient-rich, but well-draining soil. Ideally, amend your soil with compost prior to planting. Apply a 3″ layer of mulch around the tree (being careful not to pile mulch against the trunk) to help suppress weeds while improving soil fertility and soil moisture. 

If growing makruts in pots, use a high quality potting mix such as FoxFarm’s Ocean Forest Potting Soil

Pot size

When you first get a young makrut sapling, you can start by planting it in a small 1-3 gallon pot. However, you’ll eventually need to pot it up into its final, large pot. 

We use large 20″ tall x 20″ diameter pots, the largest we could find at our local Lowes. (We use plastic pots because ceramic is too heavy and often breaks.) Tip: Buy your pots in late summer or early fall when they’re on clearance sale! 

We also put a 2″ layer of wood chip mulch on the soil surface in each pot. This helps reduce evaporation, block weeds, and improve soil fertility.  

Water

You want to maintain even, damp (but not wet) soil moisture throughout the year for your makrut lime. The ideal soil moisture level is like a wrung out sponge.  

An under-watered, water-stressed makrut tree will drop its fruit. A makrut tree that gets chronically over-watered will experience root rot and also drop its fruit. 

If you have lots of potted citrus or fruit trees like we do, we highly recommend setting up drip irrigation, which will save you lots of time, money, and headaches. Read: How to set up drip irrigation for potted plants.

How much water do makrut lime trees need each day? It depends on the season and the maturity of the plant.

For reference: in the hot days of summer, our mature makrut lime tree in a 20″ x 20″ pot gets about 1.5 gallons of water daily. In the winter, it might only get 0.5 gallons of water per day.

A larger, in-ground makrut tree will need more water than our potted tree. 

Fertilizer 

Citrus trees (makruts included) are fertilizer hogs. This is especially true of potted citrus trees since their roots and microbial partners can’t extend further to get more nutrition. 

How much and frequently to fertilize your makrut trees will also vary based on: a) the size/maturity of the tree, and b) the season. Citrus needs the most fertilizer from late winter-early spring as it rapidly puts on new growth and flowers. It also needs fertilizer as it sets and matures its fruit from spring through late summer. 

For fertilizer, we use a combination of: 

  • organic citrus fertilizer (if you only use one thing, use this!); 
  • liquid gold (it’s free!);
  • liquid kelp and/or fish emulsion;
  • *worm castings and/or compost, top-dressed about 1/2″ deep then mulched;
  • *we also make sure each of our pots has worms in it, which helps keeps the soil aerated and ads some microbe-rich fertilizer as well. 

Our citrus fertilization schedule:

  • Spring – we apply a small amount of fertilizer once every 2-3 weeks.
  • Summer – fertilize once every 3-4 weeks.
  • Winter – fertilize once every 6 weeks. 

Pruning

Yes, you’ll have to periodically prune the foliage and roots of your makrut lime tree. Wear gloves and long sleeves when pruning because makrut lime trees do have painful thorns! 

As soon as the last of its fruit has been harvested in late winter, we prune our makrut lime tree by removing branches that:

  • angle down,
  • cross over other branches,
  • stick too far out of the sides or top of the canopy/desired shape.  

Root pruning is something you’ll need to do every 2-3 years once your makrut trees get rootbound or to prevent them from getting rootbound. See our detailed article and video tutorial: How to root-prune rootbound potted fruit trees

Makrut lime pest insects  

Grown outdoors, healthy citrus trees don’t tend to have much pest or disease pressure. Exception: areas where citrus greening is present, which is a deadly disease with no cure. Citrus greening is a bacterium spread by tiny insects, Asian citrus psyllid. 

If you’re growing citrus in pots in moderate climate zones, your citrus is unlikely to experience significant pest pressure while it’s outdoors. The only outdoor pest our citrus experiences is leaf miners, but they don’t do enough damage to warrant intervention. 

However, citrus trees grown indoors for months at a time are very likely to have pest insect proliferations since they won’t have the benefits of high humidity and predatory insects such as lacewings, predatory wasps, ladybugs, and others.   

Common indoor pest insects for citrus include aphids, spider mites, mealybugs, and scales. Prevention is the best course of action here. Once per month, take your makrut/citrus tree outdoors and give it a foliar spray with neem oil or similar organic/OMRI listed pesticide. (Neem oil is perfectly safe, but don’t apply indoors or it will make a sticky mess.)  

IV. Makrut lime FAQs

Here are a few common questions people ask about makrut limes:

1. What’s a good substitute for makrut lime leaves in a recipe?

Makrut lime leaves impart a very unique flavor, but if you don’t have any available and a recipe calls for them there are some suitable substitutes: 

  • regular lime juice to taste;
  • leaves from other citrus species, fresh or dried substituted 1:1 (flavor varies by species). 

2. Is Bergamot orange the same thing as makrut lime?

No, makrut limes (Citrus hystrix) and Bergamot orange (Citrus bergamia) are not the same plant. Bergamot oranges are a hybrid between lemons and bitter orange. Their fragrant fruit is about the size of a standard orange, featuring a yellow/green lime-like color, varying based on ripeness.

Makrut limes feature an intense fragrance and flavor, but they’re much smaller (2-3″) with more *wrinkled skin. (*We’ve read that breeding work in Thailand has recently produced non-wrinkled makrut lime fruit.)

We grow a dozen varieties of citrus and each is unique. Using words to describe the differences in flavors between a blood orange, standard orange, and tangerine doesn't do the fruits justice. Likewise, words don't adequately convey the unique flavors of makrut lime leaves, flowers, and fruit.

We grow a dozen varieties of citrus and each is unique. Using words to describe the differences in flavors between a blood orange, China orange, and satsuma doesn’t do the fruits justice. Likewise, words don’t adequately convey the unique flavors of makrut lime leaves, flowers, and fruit. Flavor is a far richer experience than words, so you just have to try them!  

3. How do you store makrut lime leaves? Can you freeze makrut lime leaves?

Makrut lime leaves are best used fresh, but they also can be dried or frozen for long-term storage. Storage instructions:

  • Dried – Let the leaves dry indoors for 10-14 days, then store in an airtight container like a ziplock or jar. Use within one year for best flavor. 
  • Frozen – Place leaves into freezer safe ziplock or silicone bags and remove as much air as possible from the bag prior to freezing. Use within one year for best flavor.

4. Where can you buy makrut lime leaves or fruit? 

If you don’t grow your own makrut lime tree, you can usually find the dried leaves for sale at local Asian grocery stores — or even in the Asian section at high-end grocery stores.

You can also buy high quality, dried organic makrut lime leaves online.

We’ve never seen makrut lime fruit for sale at our local Asian grocery stores or anywhere else. As far as we know, the only way to get the fruit in the US is to grow it yourself.   

5. Can you make shampoo with makrut limes/Citrus hystrix?

One traditional use of makrut lime fruit, rinds, and leaves, was to make them into a shampoo. Some companies today are now offering makrut lime shampoos which claim to help with everything from graying hair to dandruff.

Regardless of whether these claims are true, it is true that makrut limes can be made into hair shampoo.   

6. Is makrut lime an insect deterrent? 

 Another traditional (and modern) use of makrut lime is as an insect and/or pest deterrent. In fact, the reason they were called kudalu dehi (leech-lime) by native Sri Lankans is because the juice was rubbed on their legs to keep off land leeches. 

Makrut lime leaves can also be crushed in your hand (releasing the oils) and rubbed on your skin as a mosquito deterrent in the same way that catnip can be used.  

7. Do makrut limes/Citrus hystrix have any health benefits?

Makrut limes have a long history of health/medicinal use in cultures throughout Southeast Asia and modern research is providing evidence for some of these uses.

As one study states, “The whole fruit is used in traditional medicine for headache, flu, fever, sore throats, bad breath and indigestion.” The same study notes that Citrus hystrix: “… showed a variety of pharmaceutical effects such as anti-tumor, antimicrobial, anti-inflammation and antioxidant activities.” 

Other research has shown the oils in makrut lime leaves are highly effective at preventing and treating bacterial respiratory tract infections.

Likewise, essential oil from makrut lime peels was tested for effects on human behavior. Subjects in the makrut lime oil group “rated themselves more alert, attentive, cheerful and vigorous than subjects in the control group. These findings are likely to represent stimulating/activating effects of the kaffir lime oil and provide some evidence for the use of kaffir lime oil in aromatherapy, such as causing relief from depression and stress in humans.”  

Anecdotally, we can attest to the joy and awe we and our friends and family have experienced when squeezing a ripe makrut lime, thus releasing a mist of essential oils and their accompanying indescribable aroma. Makruts are an incredible plant and we’re happy to have one in our potted home citrus orchard! 


We hope this article answers all your questions about how to grow and use the leaves, flowers, and fruit of makrut lime trees!   

KIGI,

Tyrantfarms

Other citrus articles you’ll want to sink your teeth into: 

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6 Comments

  • Reply
    Randy Smith
    February 23, 2024 at 6:25 pm

    Great article on Makrut lime. Do you know where I could buy seeds or fruit for seeds? My father lives in Easley SC.

  • Reply
    Kathy Martin
    June 26, 2022 at 3:30 pm

    This is a wonderful. I live in the Boston, MA area. I have been growing a makrut lime tree since it was tiny. It was a grafted tree. I do not know whether it was a dwarfing rootstock or not, but I do prune it before I take it indoors, and the trunk is about 1.25″ in diameter. YI keep it about 3 feet tall or so. Your article was right-on — no pest problems in the summer, outdoors, but I get a gradual infestation of scale when the tree is bought indoors for the winter. It’s horrible. I try and keep up with it with alcohol and cotton swabs, but it’s a losing battle. However, I do bring the tree out in May, even when it’s still a bit cold, and gradually, the scale is controlled. But interesting that I still should be spraying once a month outdoors in winter. Not sure I can really do that here.

    I have never gotten fruit to set. Have seen one or two blooms, fertilized it, and even one teeny fruit, but it never matured. But that’s indoors in winter and I thnk the plant is just stressed.

    This year, I plan to spray it with a horticultural oil at intervals while still outdoors. I hope then, when brought in, it will solve the scale infestation. But frankly, from what you’ve wrote, seems like I won’t be able to get 100 percent of them off.

    Grew up in Florida and know all those tropical fruits. I love it when people try to grow exotic tropical plants outside of their temperature zone.

    I absolutely LOVED the root-pruning video. I am an avid, confident gardener and this was such a methodical, well-explained way to do this. Learned so much.

    I also grow ginger, turmeric, galangal and lemon grass, the latter which I buy from the grocery store and root. I’ve also grown Thai basil from rooting healthy pieces I’ve bought from an Asian market.

    I am glad I’ve discovered your website. Yay!

    • Reply
      Aaron von Frank
      June 27, 2022 at 11:11 am

      Thanks Kathy! Glad our information about makrut limes and general citrus care has been helpful for you. Kudos to you for growing so many interesting tropicals all the way up in Boston – that’s quite a challenge!

      On the topic of citrus pest control during the cold months: you could get away with an application of neem oil every six weeks instead of every four. You might have to wait for a single warm-ish above freezing day during the allotted time window, then jump on the opportunity to temporarily move your makrut plant outdoors, apply neem oil, let it dry, then move the plant back inside. It’s not unsafe to apply inside, the smell is just intense and it’s quite sticky.

      Another challenge with having citrus indoors in the winter is getting your plants adequate sunlight, which may also be a contributing factor to lack of fruit production for your makrut lime, which thrive in full sun. Modern, energy efficient windows block a lot of the light spectrum, so even a very sunny south-facing window might not be enough to keep your makrut tree making enough energy for reproduction. We recently got some tripod LED grow lights for tropicals we grow indoors year round (like Monstera deliciosa) and they’ve worked wonders. That might be something for you to consider as well. (Here’s the ones we purchased from Amazon: https://amzn.to/3OLEzzq – you can set them to automatically turn on and off at set intervals so no having to remember to turn them on or off).

      Since you mentioned a few other plants we grow and have resource guides for that you might not have seen yet, you might enjoy our organic growing how-to guides on lemongrass (https://www.tyrantfarms.com/complete-guide-how-to-grow-lemongrass/) and ginger & turmeric – including baby ginger and unusual varieties (https://www.tyrantfarms.com/how-to-grow-organic-turmeric-and-ginger-anywhere/).

      Reach out any time we can be of help and good luck with your tropical gardening adventures in Boston!

  • Reply
    J. T.
    May 19, 2022 at 9:33 pm

    Glad I found your blog, I love my makrut lime and find myself nodding with ever paragraph. My son likes the juice as limeade and I’ve tried making a few different things with the fruit with little success (floor cleaner is definitely the way I would describe the first tries).

    I’m going to have to try the flower petals, that is one use I haven’t attempted yet.

    I love the smell of the oil and need to figure out how to make it into a cologne.

    • Reply
      Aaron von Frank
      May 20, 2022 at 1:16 pm

      Makrut lime oil does have a wonderful fragrance! Whenever we have fruit in season and guests over, we give them a makrut fruit and tell them to lightly squeeze then smell it. They’re also shocked by how aromatic it is. You could certainly rub that on your skin, but I’m not sure how long it would take for those compounds to volatilize to the point of being undetectable. It’s such an interesting citrus plant. We look forward to figuring out more ways to use it in the kitchen – if you find some more good uses, please check back in!

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