Purple roseling makes an unusual houseplant

On a recent trip to Kenya to visit a friend, I discovered a plant called the purple roseling and wondered if it would make a good houseplant in the UK. Well, to be honest, at the time I didn’t know that was what it was called. In fact it really foxed me, and although it looked familiar, I couldn’t quite pin it down.

My friend lives in the Rift Valley, near Naivasha in Kenya which is pretty much on the Equator. She told me that the plant is grown in many gardens there, where temperatures range between 8 and 28 Celsius. As you can see from the pictures, it has fleshy leaves rather like an agave which suggested to me it originated in a tropical or sub-tropical part of the world. So all in all, I guessed it would make a good houseplant for me to grow in the UK.

But it wasn’t until I got home that I finally pinned down what the plant was.

What is the Latin name for purple roseling

A fellow Royal Horticultural Society committee member was able to identify the plant as purple roseling, it’s Latin name being Callisia warszewicziana. This made sense to me as the 3-petalled flowers look very similar to members of Commelinaceae or spiderwort family. This includes plants like tradescantia and setcreasea – both of which I have grown – and which have fleshy leaves, and blooms in shades of purple.

This is where plant classification and Latin naming is very useful as it helps to identify plants from their shared characteristics. In the case of this plant I had already narrowed it down to most likely being in Commelinaceae.

Where does purple roseling come from

With a name, I was now in a position to research and find out where Callisia warszewicziana or purple roseling had come from originally. In fact, like its close relatives tradescantia and setcreasea, it originates from Central America. More specifically in this case, Guatemala and Mexico.

Having pinpointed this, I could work out the growing conditions that the plant was likely to need. Guatemala lies within the tropical belt which stretches around the globe either side of the Equator. It’s hardly surprising, therefore, that the plant grows well in Kenya, where I first saw it.

There are reports of this plant attaining weed-like proportions in suitable conditions, but this is most unlikely in the UK or Northern Europe and America.

What temperature does purple roseling need

In it’s native environment purple roseling, or Callisia warszewicziana, may experience temperatures in a range of 12-28 Celsius, but is also able to cope with cooler temperatures for short periods of time. Established plants may survive down to -5 Celsius given a dry soil and atmosphere.

In addition the plants have developed to tolerate a distinct dry season, which in part explains their succulent leaves and stems. However, their native environment is subject to long periods of regular rain, as well as high light and intense sun typical in equatorial regions.

Such adaptation to a wide range of temperatures, makes the species suitable for growing as a houseplant in the UK and other cool temperate parts of the world. Regular watering during the growing season will keep the plants in good health. They will benefit from a period of reducing or even withholding water in the winter months.

All important is maintaining a good light level, so growing on or close to a windowsill that receives sun for at least half the day is recommended. The plants may also be stood outside during the summer months.

Best way to grow more purple roseling

With its rosettes of fleshy leaves and clump forming habit, the easiest way to grow more Callisia warszewicziana or purple roseling is to divide the plants. New shoots grow from low down at the base of the clump to form ‘offsets’. Like the main plant, these will be composed of a spiral of fleshy leaves attached to a chunky, central stem with fibrous roots at the base.

Simply lift an established clump from the compost or soil and carefully pull apart the individual sections. Pot these up singly into a well-drained compost with added grit and they will quickly root if kept moist. Take care not to bury the stem or the leaf bases too deeply as they can rot.