Banana plants (Musa spp.) are classic tropical foliage plants, small to medium trees often planted in sunny patios for their lush leaves and exotic flair. Of course, the trees can also produce the colorful and popular banana fruit. Some species, like the ice cream plant (Musa acuminata x Musa balbisiana ‘Blue Java’), offer both splendid paddle-shaped leaves and sweet, melt-in-your mouth fruit. If you live in a warm region, you might want to add ice cream banana trees to your garden area for a touch of tropical allure.
I. Appearance and Characteristics
The Blue Java, also known as Blue bananas, Ice Cream banana, Hawaiian banana, is a hardy, cold tolerant cultivar known for its sweet aromatic fruit. Blue Java bananas grow to approximately 10- 15 ft. tall. They are cold-tolerant to zone 8, and wind-resistant because of their strong pseudostems and root systems. The leaves are silvery green in color and their fruit’s blueish-green skin also sets it apart from other cultivars making them very ornamental.
The ‘Blue Java’ cultivar is a part of the ABB Group of bananas. Iit contains one set of chromosomes from Musa acuminata and two by Musa balbisiana. As a hybrid of a sweet banana and cooking bananas, this variety is delicious raw or cooked. The fruit bunches are small, bearing seven to nine hands. The fruit are 7-9″ in length and show a characteristic silvery blue color when unripe. The fruit turns a pale yellow when ripe, with white creamy flesh that melts in the mouth. They are known for their fragrant flavour which has a vanilla-like custard texture and taste. Blues bloom around 15 to 24 months after planting and can be harvested after 115 to 150 days.
II. How to Grow and Care
Sunlight and Temperature
You’ll definitely want to provide full sun conditions for your banana trees. They prefer 8-12 hours of sunlight a day. While they can tolerate partial shade, they just won’t grow as vigorously. So be sure your bananas get ample amounts of sunlight.
Blue java bananas are much more cold tolerant than other banana varieties. In fact, they’re so cold tolerant that they can survive with a protective wrap down to 20 degrees Fahrenheit. That’ much, much colder than other bananas can take!
Watering and Humidity
All bananas love water. You’ll find these tropicals to be thirsty! However, they don’t tolerate standing water anywhere near as well. Ensure your soil is very well-draining and that it doesn’t pool up around the plant during rain. If you’d prefer, place a soaker hose around the base and allow it to do a long, deep soaking.
Water deeply on a daily or every-other-day basis. During the summer, it’s likely to be daily. The rest of the year, skip watering if it rains significantly, and water every other day if it hasn’t been raining.
Like most tropicals, your blue java enjoys some ambient humidity. While it can survive in lower humidity ranges, a 50% humidity level is just about perfect.
Soil
Good drainage is essential for growing bananas, particularly the blue java. Like most other banana trees, its root system is susceptible to fungal pathogens like pythium that cause root rot. It’s also susceptible to fusarium. Both of these tend to develop in overly-wet soil, so make sure it drains extremely well.
Start with a sterile soil blend when possible to avoid soilborne fusarium. If it’s not possible, consider solarizing your soil months before planting to reduce risk.
If you’re blending your own potting mix, try to make sure about 20% of it is made up of perlite or other drainage aids. Use coconut coir, peat moss, or even some worm castings to provide water retention. Good quality compost is another great ingredient. If you’re adding soil, try to provide loamy or sandy soil rather than clay types.
Blue java bananas prefer the soil pH to be between 5.5-7.0. That neutral to slightly-acidic range is where they’ll grow best.
Fertilizing
Try to use a high-phosphorous fertilizer for initial growth. An 8-10-8 or balanced 10-10-10 will work. Younger plants should be somewhat diluted, at roughly 65-75% strength. If you’re using a granular fertilizer, just apply a little less for a young banana than you would an older one.
Once the tree is old enough to fruit, swap to a high-potassium fertilizer when it starts to put out its true stem. Aim for a 10-10-15 or 10-10-20. This will promote fruiting.
Don’t fertilize in the winter, as the plant will be dormant at that time.
Planting Instructions
Site selection is important. The ice cream banana is relatively cold-tolerant and quite wind-resistant, but you should still find as warm and protected a planting location as possible. For example, a sunny site next to a wall or structure could work well for ‘Blue Java.’ Plant the ice cream tree in rich, fertile well-drained soil with a pH between 5.5 and 6.5.
To propagate any kind of banana plant including the ice cream plant, you will need a rhizome. These are the plant roots that are removed from banana root clumps together with some of the parent plant’s root system and can be called suckers or pups. If you are buying from a nursery or getting a rhizome from a friend, look for a large sucker at least 3 feet tall, which is the preferred planting material.
Plant the sucker in prepared soil after pruning off all large leaves. Don’t bury it too deeply, but keep it relatively close to the soil surface. If the plant comes in a container, using the prior planting depth as your guide should work well.
Pruning
One of the best things about growing blue bananas is that they’re a minimal-pruning plant. Yes, there is some pruning required, but it’s pretty simple.
Around the base of the adult stalk, pups or suckers will form. These will become the next fruiting part of the banana plant, so be careful not to remove all of them. But the weaker ones should be removed to allow the plant to focus its energy on the more vigorous and healthy ones. Start selecting vigorous ones to stay once the current false stem is six months into its growth.
When possible, only remove leaves when they’ve yellowed or browned on their own. Leaves that are starting to shrivel usually loosen their grasp on the main stem, and they’re easily pulled off the plant at that point. If you can’t pull it off easily, leave it in place.
Once the adult stalk has produced its true stem and has finished fruiting, there’s one additional task that needs to be done. The adult stalk will only produce a single harvest of fruit, and after that should be cut back to the corm so that one of the pups can take over for the next year. Be careful when doing this so as to avoid damaging the young plants.
When pruning, always use sterilized loppers or pruning shears. This reduces the risk of transmitting plant diseases.
Propagation
Blue java seeds are notoriously unreliable, and that’s if you ever see them at all. Most of the plants in cultivation have been hybridized so deeply that they seldom produce seed in the first place, and most of that is sterile. Those rare ones that do produce potentially viable seed have very low germination rates.
So it’s best to opt for either purchasing a plant developed from tissue culture, or to carefully divide off a pup from the corm of the blue java plant. It’s a bit of a tricky process, as you don’t want to damage the corm too severely, but if you’re careful you should be able to cut through the corm and transfer the pup to a new location.
Pests and Diseases
Common Pests
An array of pests can appear and annoy you and your banana plant.
Piercing insects like the banana aphid and spider mite are common. These suck the sap out of the fronds, and banana aphids can also spread diseases. Both can be treated with neem oil, although large outbreaks may require something like pyrethrin.
Mealybugs will make a home on the leaves as well. Small outbreaks can be removed by using a cotton swab dipped in alcohol to force them to release. Use insecticidal soap to handle larger outbreaks.
Two types of thrips, banana rust thrips and corky scab thrips, go after bananas of all sorts. Both can cause severe damage, although the rust thrips go after the leaves and skins of the bananas while the scab thrips go after the fruit itself. Use pyrethrin to control these.
The coquito, also called the banana fruit scarring beetle, attacks the fruit directly as the name might suggest. Use sticky traps to catch adult beetles.
Root knot nematodes can cause a real problem for the rhizome of your plant. Apply beneficial nematodes to deal with both these and the coquito larvae.
Finally, we come to black weevils, also called banana stalk borers. These cause major damage to your plant, and pyrethrin should be used to eliminate them.
Common Diseases
The worst disease for any banana species is fusarium oxysporum. This fungal pathogen causes the dreaded Panama disease or banana wilt and is lethal to your plant. Drooping fronds and yellowing leaves lead eventually to plant death. There is no cure for this disease, and it can be transmitted by wind, water, infected soil, or uncleaned tools. If you encounter it, you will need to not only destroy your plant, but not plant another banana in the same soil. It has wiped out entire strains of bananas.
Two types of leaf spot, sigatoka and black leaf streak, can appear on your plants. Thankfully both of these are treatable with a liquid copper fungicide.
Banana aphids frequently spread banana bunchy top disease. This disease causes leaves to curl upward and the plant may develop more narrow leaves. Leaves can become brittle and stiff over time as well. There is no treatment, but prevention of aphids will prevent your plant from getting it.
Finally, there is a strain of mosaic virus specifically for the banana. Like all mosaic virus strains, there is no treatment for it. In this case, it causes streaked leaves and fruit. Destroy infected plants.
III. Uses and Benefits
Blue Java’s are regarded as one of the best tasting bananas in the world and they can be eaten fresh or cooked. The fruit goes well with ice cream. They are also popular as an ornamental shade plant for their unusual blue and silvery coloration, large size, tolerance to wind, and suitability to temperate climates in zone 8 or higher. Blue Java / Ice Cream bananas do very well in large containers for those in climates colder than zone 8.
IV. Harvesting and Storage
Harvesting
You’ll know the blue java fruit is ripe once the blue tint has faded away from the banana peel, leaving only a mellow yellow tone. The petals at the end of the banana will dry and turn crisp, signifying that the banana is ready to harvest. Often, the ones at the top of the bunch will be the first to ripen, but once they’re ready, you should harvest the whole bunch.
Have a friend on hand to grab onto the bunch, which will have some weight to it. Cut through the true stem above the bunch, then gently lower the bunch down to the ground. Go through and use a sharp knife to cut off each individual hand, being careful not to damage the skin of each of your java bananas.
Storing
The topmost bananas in a bunch will usually be the ones you’ll need to eat first. The rest will slowly ripen over time, but like all bananas, the blue java banana will ripen pretty quickly once harvested. You’ll suddenly go from no ripe bananas to all of them ripe at once!
Due to its gooey texture, the easiest way to store these is for long periods of time is to skin them and store the fruit in the freezer. You can leave it whole or mash it into a paste as desired. If mashed into a paste, a scoop of the frozen pulp can be used to substitute for real ice cream, making it a delicious natural treat.
