Banana trees will grow as tall as 40 feet in the right conditions. The taller stems often are the first to grow banana bunches but height is not the only factor. Strong, healthy stems are important for banana trees to bare fruit. The heavy bunches can be heavy so they need a thick stem and a strong attachment to the rhizome to stay upright.
This article will explore how tall banana trees grow as well as the conditions that can get them to grow as tall as possible.
How tall banana trees grow
Banana trees grown in tropical climates in well-draining soil with healthy and strong rhizomes can grow to 40 feet tall or more. They can grow up to 3 feet in 1 month if they have the water, nutrients and sunlight they need.
They need a strong base where their large rhizome is solidly attached in the ground so the plant can reach the water in the soil it needs. The large rhizome will also help to stabilize the banana stems. Each individual stem can be incredibly heavy as it is full of water and sap.
Some banana species are taller than others but the popular cavendish banana can easily grow to 20 feet high. You can remove stems that have grown larger than you would like by pruning them near the base of the root system.
The tallest banana species is the giant highland banana (Musa ingens) which can grow up to 49 feet in height.
The banana tree will send up new stems to replace them which can be trimmed again once they outgrow the space.
Take care when planting banana trees in your backyard. They can grow tall and fast. They can also spread quickly as the rhizome sprouts new stems regularly throughout the year.
Conditions that are needed for tall banana trees
To grow the tallest banana tree possible there are a few conditions that need to be met. Check out this list of conditions needed for large and healthy banana plants
A healthy rhizome
To grow a large banana plant you need to start off with a healthy rhizome. This is the root system that the banana stems will grow from. They grow similar to a tulip or bird of paradise in that they grow from a large rhizome that sits at the base under the soil.
NOTE: Banana plants are classified as a herb and can continue to grow new stems from their rhizome when the old ones are removed.
If the rhizome is strong and healthy it can support a large banana plant and large stems. Once these stems reach their maximum height the banana plant can send out a flowering stem to produce fruit. Modern banana species do not need to be fertilized by a male flower to grow bananas.
Limited number of stems
A banana plant that has a maximum of 3-4 stems will generally grow these stems larger. If there are too many stems the nutrients and water will be spread out to all of the stems and they will not grow as tall.
To grow a large banana plant with a few tall stems that will produce fruit, aim for 3-4 and remove the rest. Banana stems are easy to trim off with a pruning saw or you can snip them off with secateurs if they are small.
Cut them off near the base of the plant. Let the stem dry and you can put it in your compost. Run it through a mulcher if you have one to help it to break down fast.
Regular water
Banana plants need regular water to grow stems as tall as 40 feet. They do not grow deep roots, instead grow roots that will stretch out wide to reach as much surface water as possible. These tropical plants love lots of water during the summer where their growth will be rapid.
If you get regular rainfall during summer these banana plants can survive on rainfall alone. If you live in a dryer area or you are having a dry summer then you will need to top your banana tree up with water.
I often notice on hot summer days that my banana plant leaves will start to droop. I will usually wait until the end of the day and then deep soak the plant. By the next morning the leaves will be standing up again.
Banana trees can need watering up to 3 times per week during very hot summer days. Keep an eye on your plant and water it deeply if the leaves are drooping and the weather is dry.
Well-draining soil
Banana plants need well draining soil to grow well and as tall as possible. Plant them in free draining potting mix if you are growing them in pots. Before planting banana plants in the ground improve the ground soil so that it drains well.
Dig through bags of aged cow manure and compost and throw in a few handfuls of chicken manure before planting your new rhizome. Your banana plant will grow rapidly and spread its roots out far to reach the water and nutrients it needs.
A good source of nitrogen
Banana plants will grow best with added nitrogen at the start of spring. Adding a good, all purpose fertilizer like pelleted chicken manure will give the plant the nitrogen boost it needs to grow tall. You can also top dress the soil around the plant in spring with some added aged cow manure and compost.
Cover the top dressing with 3 inches of straw or bark mulch and water the plant well. This will give the banana extra nutrients gradually over the next few months to encourage lots of leaf growth and healthy, tall stems. These stems can be ready to grow fruit within 9 months if the plant has the nutrients it needs.
Full sun position
Planting banana plants in a full sun position is essential for them to grow as tall as possible. The sunlight will allow their big leaves to photosynthesize creating the carbohydrate the plant needs to build tall stems. Banana plants grown in full sun will grow twice as fast as those grown in shade.
How Tall Do Banana Trees Grow? | Summary
Banana trees will grow as tall as 40 feet if they are growing in ideal conditions and are not pruned. If you want to keep the plant smaller, trim back the stems that are growing tall and allow the plant to replace them with new ones. These smaller stems can be cut back as soon as they reach the desired side.
Keep in mind that if you want your banana trees to actually grow bananas you will need to let the stems grow as tall as possible. These tall stems are usually the first to grow banana flowers and eventually fruit. Bananas can take many months to mature and ripen but they are worth the wait.
Happy growing.
I am an accredited practicing dietitian, experienced gardener and a dedicated cook. I love writing and sharing my experience so you can learn from my successes and mistakes.