The 5 Reasons Why Your Mint is Leggy (and What To Do)

Having long bare stems with a handful of bad looking leaves here and there is not exactly what you want for your mint. What caused that and how to solve it? Here the 5 most common reasons and solutions explained in easy words with tips along the way.

Why is your mint leggy? A leggy mint with just a few stems and only a handful of leaves is the result of one (or a combination) of these problems:

1. Root bound: a container too small
2. Lack of pruning: it makes a massive difference
3. Too much fertilizer: mainly nitrogen
4. Lack of light: stems stretch for resources
5. Low temperature: only if left outside

Should you throw your hardly grown mint and go for another one? Not so fast. First, you need to understand which is the problem your herb is facing and then take action accordingly. These guidelines apply to both mint in a container and not (in case just skip the root bound problem).

Leggy Mint: Many Potential Problems and One Good News

Good news first

Mint, by many, is seen as an invasive species, a bit like a random and unwanted weed. Countless gardeners with outdoor garden complaints about mint invasion (I wish to have such a problem if the mint is of good quality) and how to get rid of it.

Why is this important to your leggy mint?

Although this might sound like a bad attribute, this means that mint is an extremely stubborn herb that can survive a large variety of conditions and “mistreatment” from you or whoever takes care of them. Indeed, to be such an invasive plant, mint needs to be (and it is) very strong and resistant. Hence, even if its legginess is due to some unwanted mistreatment, it will very likely recover in 1-2 months. So do not give up!

Let’s see which problems your mint might have and how to solve them.

1 – Root Bound

Rootbound is a condition that affects potted plants when their roots have extended throughout the whole soil, reaching the container walls and pushing against them. This creates a thick solid web of roots (also known as root ball). In extreme cases, there might be more roots than soil.

Why?

A root bound takes place when the pot is simply too small for the herb. Have you planted your herb as a seedling in a small pot and then left it there? Then you have the answer to why your plant is not root bound.

A root-bound mint is very likely deficient of minerals and/or water. This is because a root bound mint has very little soil in the container (as it will be filled with roots) and so a limited amount of nutrients and water (as a little amount of soil can hold only a little amount of water and nutrients) that the roots can exploit.

This, in turn, makes the situation worse as it is also scientifically proven that plants to stimulate growth to develop more roots if in a nutrient-deficient environment.

Bottom line? Many plants cry for space when they want to develop!

Solution?

If you suspect your mint is root bound, just have a look at the article below. It will tell you how to identify the root bound and how to solve it step by step.

2 – Lack Of Pruning: Why This is a Must

I know, you might be concerned about pruning your mint, especially if it is leggy. However, do not. Pruning your mint, in the right way, is the best thing you can do.

Why?

Indeed, gardeners, way more expert than me, agree that many culinary herbs (like basil, rosemary, thyme) do enjoy pruning. Indeed, each time you do it right, your mint, like a hydra, will multiply. From one shoot, they will become two. From two, four, and so on! In no time (well a few weeks), your leggy mint will become a bush!

Solution

You need to prune your mint, in the right way.

Mint needs to be pruned just above a node. As you can see in the picture below, a node is a point when the leaves branch out. After you cut, you will see in a few weeks, two new branches coming out from the side of the node.

Remember: I do personally do not cut back more than a third of the stem (roughly). If you cut away too much, your mint might struggle to survive as it does not have leaves to leverage the sunlight, and it might die.

3 – Too Much Fertilizer: Tall Stems and Only a Few Leaves

Despite fertilizer being a great allay, especially for potted mint that might not receive enough nutrients from the soil, it is also a danger. Indeed, if you do not follow the instructions in the label (and actually, I usually place half of what the label recommends), you might get in trouble.

Why?

Indeed, a mint (as any other plants) when over-fertilized will produce massive stems and leaves as well. However, the problem is the root here. Indeed, the roots are not developed enough. Indeed, such an important amount of green material developed in a short period of time (due to the injection of nitrogen), would have appeared naturally through lots of roots (and lots of time). Hence, you will have a plant that is not “structurally” ready for that greenery. Results? Your mint will bend!

Solution?

First (quite obvious), you just need to stop fertilizing.

Second, let the soil dry and then water it quite heavily. Water and let the water come out from the drainage holes for 10-15 seconds. Why? Because the nitrogen in your soil can be (relatively easily) washed away. Hence, the water that will drop from the drainage holes at the bottom of your planter will take, with it, a good chunk of nitrogen that was in the soil preventing the situation from getting worse.

Third, I will prune the mint as discussed in the previous section so as to develop naturally new stems and roots.

4 – Lack of Light (Especially From Seedlings)

A leggy mint might just be the result of your plant looking for light. Indeed, if there is no light source (mint as well as many other plants) will develop a few and small leaves to focus on producing long stems in the hope of reaching some light source. What’s the point in producing leaves that convert light in energy if there is no light after all.

In this case, it is easy to understand if the lack of light is a problem. Are you providing at least 6 hours of direct sunlight? If no, then you have the culprit.

This problem affects seedlings quite badly. If you start your basil from seedlings, make sure, after they come out from the growing medium, are in, to provide light. Otherwise, they will grow long stems. Once this start might be a problem for the whole plant.

Solution?

You need an adequate light source. This can be either natural or artificial.

In the case of nature, think about your house. Do you have another place where you can place your mint? Perhaps in the living room? If the pot does not fit in the living room (that was my problem as the balcony was getting less sun than the living room), there are great cover pots (ceramic my favorite by far) like this one on Amazon for instance.

In case you go for artificial light (yes, plants can thrive in artificial light), there are plenty of good options. I would go for a relatively inexpensive and high quality led type of grow light. One of my favorites is one that is cheap and very versatile to use (not bulky and that I can place wherever I want). The Yoyomax grow light on Amazon, for instance, might be a very good option. You can also fix in a chair or any other furniture you have a home, it is quite lightweight, and it is more than enough for one or two mint plants.

5 – Low Temperature

This should not be a problem if you have a potted mint indoor. However, you (as many other gardeners) might be tempted to leave it outside to boost its growth (and it does as they have more sunlight) and forget it. Then autumn comes, and with it close to freeze temperature. This is a problem.

Did your mint stay outside when the temperature was around freezing for a week or so? Then except your mint to lose leaves, branches and look quite leggy.

Solution

In this case, the solution is pruning but quite aggressive. You have to cut from the base of the mint (the woody part) all the stems (yes, all of them). Some of them might still look alive, but I would not worry.

Your mint has a hidden and strong special root system (rhizomes) from which it will develop new shoots in one-two weeks (of course if not freezing).

If the temperature is still low, you can either wait or (after the harsh pruning) bringing it indoor. You should start seeing some new shoots coming from the ground in one or two weeks.

Check out the good video below.

How To Prune & Feed Scraggly Mint To Promote New Growth / Joy Us Garden

Lack of Water or (and) High Temperature

Reading around many attributes, a leggy mint to lack of water and excessive heat. I disagree.

Indeed, both situations lead to very similar effects. Indeed, in both cases, mint will suffer from dehydration.

The lack of water will lead the leaves (where the higher amount of water is stored) to dry out. They will get “crispy” and brown. This is not related to leggy mint. A leggy mint is a plant that can easily survive for the long term although it is, at the moment, in not ideal conditions. On the other hand, an underwater mint is going to die pretty soon.

Mint Disease

So far, I have assumed that your mint is disease-free. However, reading around, I noticed that people confuse a mint with problems with a leggy one as they did not look closely at the leaves.

If your mint has some kind of disease (or pests) should not be that hard to notice. Check the leaves very carefully.

1. Do you see any insects on them (white fliers, black flies, aphids?). Remembers, some of them are quite small!
   
2. Are the leaves getting strange patches (brown tips, little black spots, white)?

If the answer to any of these questions is yes, then your mint might suffer from a problem in which the leggy look is just one (side) effect.

In this case, check carefully. Does it have black spots? If so, check the article below. It applies to basil, but they share a few common problems with mint as well (especially pests). Good luck, and do not give up!

Related Question

Should mint be cut back? Yes, mint, like other herbs, is a plant for which, once it reaches around 5-6 inches in eight, can be cut regularly to stimulate (and limit) its growth. This applies to both outdoor and indoor mint, although for outdoor (due to the higher light exposure), a more frequent pruning (up to once/twice a month) might be necessary.

How to tell if a mint plant is dead? Mint plants might give the impression of being dead, especially after a long winter when all the stems are woody, and no leaves are left. However, it might still be alive and ready to sprout. If possible, bring the plant inside (if in a pot). Water thoroughly and let it sit under the light for a couple of weeks. If no new growth comes out from the soil, then the plant is dead.

The last thing is to verify the presence of any rhizome within the soil (those are roots that can originate new plants). Take out the plant from the pot and verify their presence. They are easy to spot due to their white/green color and thickness.

Spearmint or Peppermint?

Mint is a very broad term that identifies dozens of different species of plants. Two of the most famous are spearmint and peppermint? Never heard about it! Well, one is amazing for cooking while the others are more suitable for some ice cream. Which one to choose? Which one to grow? Here a guide that will tell you which one!

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