Growing Hardy Banana trees
Let me be honest here, I’ve grown these for a few years and I think the hardiness rating is somewhat overstated by some nurseries
Varieties
Musa basjoo is the most commonly sold of the hardy banana trees and it is indeed the hardiest of the bunch.
You’ll also find Musaella lasiocarpa and Musa sikkimensis sold as hardy banana plants but I believe these to be less hardy than Musa basjoo
Hardiness
As with many perennials, the older the plant gets, the hardier it becomes but sometimes getting through the first few years can be challenging.
And the Musa basjoo is rated a USDA 4/5 in my books. (4 if really well protected, 5 if regularly protected)
Feeding
The first thing you have to understand about hardy banana plants is that they are heavy feeders. If you want to see your plant grow well into that garden giant, you have to feed regularly.
I put a thin layer of compost on top of my potted plant and also tend to feed it every 2 weeks with a liquid plant food. I should probably feed the potted plants every week for maximum growth.
Sunshine & Water
You also want to plant your hardy banana pet in full sun although I find my Musa basjoo does well in a part shade spot. My problem this past year was that the only sunny spot I had was also one of the windiest and banana leaves are quickly shredded in a wind. They are very fragile and don’t take much abuse. (They reminded me very quickly of the plantation plants I’d see in the islands rather than the cultivated look I was seeking for my garden.)
Hardy bananas love water. It seems these things dry out as soon as you take away the hose. The kicker here is that they will not survive in standing water or heavy soils as they will also rot quickly. So your soil has to have great drainage but you have to provide a lot of water.
I watered my pots almost every day in the heat of the summer. I used a regular artificial soil for my plants although I know some gardeners who add upwards of 25-30% sand to the mix.
How do you know you are treating your hardy banana plant properly?
If you don’t get a new leaf every week – every 5-7 days outdoors – you are either underfeeding or underwatering. And the big question,
How do you overwinter this plant?
There are several answers.
You can take it south with you although a 6 foot hardy banana tree doesn’t travel well in the back seat of a compact car.
You can overwinter it in a pot like I do with at least one to ensure I have more for next spring. This picture is my Musa basjoo the day after I brought it indoors for the winter. I note this one started as a pup in the late spring and grew all summer in this pot.
You can mulch it. Here’s the trick folks. Mulch. Once the cold weather has well and truly hit – the plant has been hit by a first frost and the leaves are all curled with frost. Cut the hardy banana plant to the ground. Do not let those leaves and stems rot as the rot will go to the roots. Do not mulch right away but let the cool weather tell the plant that it is indeed winter. Once you’ve had a serious frost, then mulch.
The trick is to cover it with a solid six to eight inches of mulch (but more – up to twelve inches in colder areas is good too). I use straw or peat moss.
The second thing in cold climates where you’re going to have a spring thaw before you have spring (think melting snow and ice and then refreezing) is to cover this mulch with a plastic sheet or something to keep the mulch dry. This is why peat is good – the top inch or so might get soaked but because it resists wetting, the bottom will stay dry.
The objective is to keep the damp away from the root to prevent rotting. Wet mulch on top of a root is not a good thing to have.
In the early spring, before growth starts, remove the plastic, remove the mulch (or most of it anyway) and let the plant come back when the ground warms up.
If you want to grow this plant quite a bit larger, then use the cage method. Build a cage of wire around the plant (several feed wider than the stem at all parts) after you’ve pruned the leaves off and the stem back a bit (you actually leave the stem above ground with this method, simply removing the leaves) then fill the cage with insulating mulch.
Again, it can’t get wet and it has to be a lot of mulch to protect the stem. I would suggest you spray heavily with a fungicide like lime sulphur before you cover with mulch as you’ll likely have fungus developing next to the stem. I prefer the previous method as this method is too much work for me. I pass it along for your amusement.
If you’re used to overwintering tender azalea in this way, then one more plant will not bother you. This system will work in areas where winters are not as severe as a USDA zone 4. In these colder areas, I suggest you’ll lose your hardy banana to fungus before you’ll keep it alive all winter. But – go for it if you have more than one banana (see below)
Blooming?
The thing about growing hardy banana plants up north is that you’ll seldom see them bloom. Because they get whacked to the ground and the season is short, they won’t have the energy or time to produce a blossom. This isn’t a major handicap as the hardiest Musa basjoo isn’t edible unless you are very, very hungry.
Propagation
Getting more bananas is not very difficult as you can see in the picture of my banana is my office. The “pups” on the bottom are new banana trees and in the spring simply divide them off the mother plant and give them their own pot or garden space.
I use a shovel and I’m not very kind about it I’m afraid; I just whack them off and repot.
I then repot the mother plant as well in new soil. Give them enough water and you’ll quickly see growth.
Pests
The major pest of this plant in my experience is spider mites. I’ve had banana trees in my greenhouses and gardens and as soon as you bring them indoors, the mites spring into life. You’ll have to regularly spray the plant with insecticidal soap to control this pest (every 7 -10 days) Watch for the mite webbing under the leaves and at the growing tip and spray these areas thoroughly. Mites will appear, trust me on this.
In the spring, before I put them outdoors, I spray them thoroughly and then the natural predators seem to work fine all summer. But indoors in the winter is another story.
And that’s how you grow a banana tree.
Questions and Answers
I have a red banana tree - the leaves are dying from the bottom and it looks like I have spider mite. What should I do?
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