Our banana plant was getting brown leaves and we weren’t sure how to fix it. So, I did some research. Here’s what I found about banana plants and brown leaves.
Banana plants most commonly get brown leaves from improper watering, climate, or nutrients. If the plant was recently moved, the brown leaves are likely from transplant shock. For best results, only water when the soil is dry, use quality fertilizer, and provide a warm and humid environment.
If your banana plant doesn’t have solid brown leaves but has brown spots instead, this is usually from disease (more on this later).
So, brown leaves on banana plants are caused by several issues but do we know which issue it is, and from there—how do we fix it? Let’s take a look at the details.
Over or Under-Watering
Over and under-watering banana plants leads to brown leaves, with under-watering being the most frequent cause. Too little water and banana leaves will curl, brown, and drop. Too much water causes root rot and the leaves will droop, brown, and drop. Only water when dry and provide 2 inches of compost and mulch.
When banana plants are under-watered, their leaves curl to conserve moisture. If left for too long, the leaves will begin to dry further and brown. Occasionally, this leads to leaf drop, although some banana plants keep their brown leaves. Under-watering is common in hot and dry climates, in which soil moisture can be evaporated in a matter of hours.
On the other hand, over-watered banana plants often cause stagnant water in the soil and root rot. Once this happens, the banana plant becomes stressed until the roots can have a chance to dry out a bit and fight off the root rot mold. If left with root rot, the roots will decay, leading to more brown leaves before killing the plant.
While there is a lot of information out there about how to water plants, the best rule is to only water when the soil is dry. This prevents both over and under-watering as you’re only watering when the plant needs it.
Also, providing 2 inches of each compost and mulch goes a long way to helping the soil hold more water and increase the water independence of the plant. It also encourages deeper roots that can access deeper water. However, this should only be done once the banana plant has well-draining soil as these practices can make poor drainage worse.
Here’s a bit more information about compost and mulch (and why they’re so beneficial for your banana plant).
Compost provides valuable nutrients to the soil and increases the soil’s richness and water retention. For example, every 1% increase in the soil’s richness can hold an additional 20,000 gallons of water per acre (source).
Compost also feeds beneficial soil life such as earthworms and mycorrhizal fungi—which provide even more nutrients and disease resistance for the plant.
Mycorrhizal fungi promote many aspects of plant life, in particular improved nutrition, better growth, stress tolerance, and disease resistance.Department of Biology, University of Fribourg, Switzerland
Mulch protects the soil (and the beneficial soil life) from drying out in the sun and wind. In hot and dry weather, mulch dramatically reduces evaporation and locks in moisture from the soil. In cold weather, mulch provides a layer of insulation for the tree and its roots. Some good mulches for banana plants are leaves, bark, pine needles, and straw.
So, to recap:
Once you have well-draining soil, only water banana plants when the first 2-4 inches of soil are dry. I check for this by pushing a finger into the soil. Then, apply 2 inches of each compost and mulch under the drip line of the plant, keeping them at least 3 inches from the trunk. Reapply compost every 1-2 months.
Banana plants are natively from the tropics, so they prefer warm, humid environments. However, this is a generalization as there are a few cold-hardy varieties.
Climates that are too cold or hot and dry quickly pose a problem for the tropical-loving banana plants. In dry areas such as California, Arizona, Nevada, and parts of Texas, banana plants lose moisture from their leaves and soil quickly.
Much like humans, plants breathe and release moisture when hot. For plants, this is called transpiration. When the climate is too hot and dry, the transpiration and root moisture can’t effectively keep up and cool the plant and its leaves. When this happens, the banana plant’s leaves curl, brown, and sometimes drop.
So, the hotter and drier the weather, the more energy the tree uses to transpire and survive, and the less energy it has to use to establish its root system and grow. This drain of resources can quickly stunt or kill the plant.
For best results, keep banana plants in a warm and humid environment if possible. If the sun is too hot, and the tips of the leaves are browning, provide shade or move potted banana plants indoors. When bringing potted banana plants indoors, take care to avoid the hot and dry air from the central heat.
I found out about the effects of central heat the hard way. We had a surprise snowstorm last year here in Austin, Texas, and I moved my potted Meyer lemon tree inside. However, it quickly started losing its leaves. After moving it into a cooler room, it quickly started growing new leaves (see the photo below).
Also, for banana plants in greenhouses or indoors, many banana plant owners highly advocated placing 1-2 humidifiers nearby to make their banana plants much more comfortable. Along with placing near a sunny window, these conditions help mimic the tropical environment that banana plants prefer.
Keep in mind that if you are growing a more cold hardy banana plant, brown leaves and dieback in the winter is normal, and the plant’s pups should grow again in the spring.
By the way, if you live in a dry climate, and you’d like more information about the best drought-tolerant fruit trees, you can check out my other post: 30 Best Drought-Tolerant Fruit and Nut Trees (Ranked).
If a banana plant is recently planted or repotted, and its leaves are turning brown, it’s likely due to transplant shock. Transplant shock occurs when the plant is exposed to a new environment and has to establish a new root system. Avoid transplanting unless necessary as it can take up to 1 year for recovery.
Like many plants, banana plants are vulnerable to transplant shock, which can take up to a year for them to recover from. To help avoid transplant shock, I like to plant with the following steps in mind:
- Have the new ground (or pot) prepared
- Remove as much of the tree’s current topsoil as possible, without damaging the shallow roots
- Grab the base of the tree’s trunk and wiggle lightly
- Using your other hand, scoop up and support the rootball
- Lightly place the tree in the new ground (or pot) and fill it in
- Make sure the soil is at the same level on the trunk as before
- Apply 1-2 inches of compost and mulch to the top of the soil
- Water generously and add more soil as needed
Lack of Nutrients
If you’re using chemical fertilizers, provide banana plants with a balanced NPK (nitrogen, phosphorus, and potassium), such as a 10-10-10. Alternatively, you can apply 2 inches of compost every 1-2 months. Unlike chemical fertilizers, compost has many other benefits such as improved water retention.
Too few or too many nutrients causes brown leaves on banana plants. With too few nutrients, banana plants can’t support their leaves’ requirements, which then start to brown and die. Too many nutrients chemically burn the plant and lead to browning and dropping leaves. Ideally, provide quality fertilizer or compost.
Keep in mind that soil pH is equally, if not more important than nutrients. Without a proper soil pH, the banana plant’s roots will be unable to absorb nutrients in the soil. This leads to browning and dying leaves.
Generally, banana plants prefer a soil pH of 5.5-7.0.
You can measure soil pH with pH strips or a pH meter. I prefer using a pH meter since they’re easy to use and affordable. To see which pH meter I use and recommend, visit my recommended tools page.
Why Banana Plant Leaves Get Brown Spots
Some brown or yellow spots on banana plant leaves are normal, but excess spots can be caused by excessive fertilizer or fungal diseases such as Black Sigatoka. If the spots are becoming an issue and affecting the plant, prune infected leaves and provide a safe spray. Also, hold off on fertilizer and flush the soil.
If your banana plant is infected with a fungal or bacterial disease, fertilizer can feed them—often making the issue worse. Too much or too strong fertilizer can also chemically burn the plant’s roots and cause and brown spots. If you believe this is the case, flush the soil with soft water.
Hard water, such as tap or irrigation water, often adds excess salts and chemicals to the soil. Because of this, flush the banana plant’s soil with soft water, such as rainwater, distilled water, or reverse osmosis water.
On the other hand, if you find the yellow or brown spots to be a disease, prune the most infected leaves (leaving enough to photosynthesis) and apply a safe spray.
Despite popular belief, there are safe, organic sprays out there. For example, check out this homemade, non-toxic fungicide by Stefan Sobkowiak – The Permaculture Orchard.
Should You Cut Dead Leaves Off of Banana Plants?
Banana plant leaves should not be cut off unless they’re diseased or completely brown and dead. Even if they have some green, they’re still photosynthesizing and holding moisture around the plant. This is also true for banana plants that have broken leaves.