How To Grow The Lucky Bean Plant (Castanospermum Australe)

Native to the eastern coastline of Australia, Papua New Guinea, and the Pacific Islands, the lucky bean plant makes a fabulous houseplant, as long as you have a lot of room.

They’re not particularly demanding when it comes to light, and it helps that these beautiful plants grow from a distinct bean that sits on the surface of the soil, helping to create a unique look in any room.

Interested in growing your own? Let’s take a look.

At A Glance: What You Should Know About The Lucky Bean Plant

The lucky bean plant is part of the pea family, Fabaceae, and forms the only plant species in the genus Castanospermum. 

You might also know this plant as the magic bean plant, black bean, or the Australian chestnut.

This is an evergreen plant – a tree in its natural environment, growing up to 130 feet tall in the wild. Luckily, it won’t get anywhere near this indoors, and the growth is easily managed by trimming the plant and keeping it in a pot.

It’s more likely to reach about 4 to 7 feet tall, and 2 to 4 feet wide inside. As it is a plant native to the rainforest, it doesn’t need a huge amount of light, making it perfect for indoor cultivation.

The foliage is attractive as a houseplant choice, each leaf able to reach 15cm long. While it’s unlikely that it will flower indoors, the lucky bean plant features red and yellow flowers, each one capable of growing 4cm long.

These are followed by fruit pods that can reach 20cm long, containing around 5 seeds that look a little like chestnuts.

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It’s worth noting that a lucky bean plant looks better with several plants in the same spot, as the plant can look a little spindly on its own. If you live somewhere warm, you could even grow it outside.

Otherwise, indoors is best, where it can get the kind of temperatures it has adapted to. 

How To Propagate A Lucky Bean Plant

Unlike most houseplants, the best way to grow a lucky bean plant is through sowing seeds, rather than taking cuttings.

The seeds look like chestnuts and will germinate on the surface of the soil rather than beneath, so you will see results as quickly as possible. 

It’s worth noting that the seeds need a temperature between 64°F and 77°F (or 18°C and 25°C) to germinate. Anything colder will not wake up the seeds.

You could try growing a lucky bean plant by taking stem cuttings from an existing plant, but this is much more difficult, and you will have to be patient. 

To increase your chances of success, put the cuttings straight into a plastic bag to keep what water they’ve got while you transport them to their pot. 

Dip each one in rooting hormone before planting, and use a heated propagation mat under the pot. Pop a clear plastic bag over the container with a few holes in it for ventilation, and this will help maintain the humidity needed.

Soil Requirements

Lucky bean plants like a lot of nutrients, so use a rich compost that has plenty of drainage. Some people have said that these plants will also grow in compost formulated for cacti and succulents, so use what you have at hand and see what works.

You’ll want to replace this compost every year or so when you keep the plant in a container, as it will use up the nutrients fairly quickly.

When To Trim A Lucky Bean Plant

Giving your lucky bean plant a trim now and then helps to invigorate the plant’s growth, and also keeps it from getting spindly. It also means that the plant won’t get too large.

Always remove dead or dying branches when you see them, to stop any problems from spreading. 

These plants will respond well to pruning at nearly any time of the year, but don’t overdo it. Take off anything that needs trimming every few months or so.

How To Repot A Lucky Bean Plant

Always check the bottom of the container every few months to see if any roots are coming out of the drainage holes, as this is the plant looking for new soil.

Expect to repot a lucky bean plant every two years or so, but this may be more or less depending on the growing conditions. 

When repotting, always use a pot that’s one size bigger than its current home, making sure there is plenty of drainage. 

Use fresh compost when repotting your lucky bean plant, and water it lightly after transferring it into its new pot. 

It’s worth noting that this plant does have strong roots, so don’t wait until it’s completely root bound to repot it, otherwise, it can break the pot!

Lucky Bean Plant Care And Maintenance

The lucky bean plant is very easy to take care of, as long as you give it the right care and the right amount of light and water.

Let’s take a look.

Sunlight And Position

Lucky bean plants prefer low and filtered light, as they are used to the forest floor when they are just emerging from the seeds, which tends to be very dark. 

You can train it to cope with much brighter light, but it will need to be gradually introduced.

When To Water A Lucky Bean Plant

When you need to water a lucky bean plant depends on the surrounding temperature and environment. 

As it has adapted to live in high levels of humidity, this plant doesn’t like drying out completely, but you have to err on the side of caution because too much water will kill it off.

If the soil that you can reach from the drainage hole is dry, it’s time to water it. This might be every week or two weeks. 

You can also mist the plant to give it a boost of humidity, but make sure you do it early on in the day so that the droplets don’t scorch the leaves when the sun hits it.

It’s worth noting that a lucky bean plant will mostly go dormant in the winter, and while it won’t need a lot of watering, it will need some as it doesn’t like drying out completely.

Humidity Requirements

Keep the lucky bean plant away from drafts and radiators, and preferably keep it near other plants which will raise the humidity levels.

When To Feed A Lucky Bean Plant

A lucky bean plant does not need feeding during its first year, as the seed it emerges from has everything it needs in terms of nutrients for a while. 

Once it has gotten to a year old, these nutrients will be spent, and you can use a weak houseplant feed from spring onwards, but make sure you don’t feed the plant come fall or winter.

Pests And Diseases To Watch Out For

Overwatering is the biggest issue you need to avoid, but these plants can also suffer from scale and spider mites.

Final Thoughts

The lucky bean plant is a fabulous choice for areas that need a larger houseplant while being relatively easy to take care of.

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