Rabiea difformis (2016)

By Bob Williams (June 2016)

As the plants from the April plant sale were going to new owners, two little plants remained, unappreciated by all and begging for a loving and caring home. One of the plants got me; the lucky one was selected by Jolie Krupnik.

My plant, Rabiea difformis, got off to a rocky start. The plant originally had five crowns, each containing six leaves coming from the base. The weekend after the sale, I was repotting my purchases, and I noticed that two of the crowns were squishy and were not going to make it.

I grabbed my knife and cut the two off, coated the cut areas with sulfur and potted the plant. Then, 10 days ago, another crown showed the same symptom. Again, out came the knife and sulfur. The remaining plant is doing well.

I decided to find out how to grow this plant before it was too late. My research surprised me.

Rabiea is a member of the Aizoaceae family and is considered a mesemb. There are only seven species within this genus. All are found in the Eastern and Northern Cape region of South Africa. Rabiea difformis grows in the Cradock district of the Eastern Cape region in South Africa. This is also considered part of the “Karoo” region of South Africa.

The plants grow in the higher elevations of the region. This area of South Africa receives heavier rainfall in the spring. The summers are warm, and the winters are cold, but tend to be dry.

These plants are considered very hardy, but slow growers. They are small plants that may only grow 2 inches tall. As the plants mature, they create a large tuber. From this tuber, new offsets grow.

Over time, Rabiea difformis will create a round mat. When the mat is too large for its pot, the offsets can be used as cuttings for propagation. As the tuber of Rabiea difformis grows, many people raise the roots, creating a caudex.

The normal growth period is spring and summer, but if grown in pots and brought indoors, they can be opportunistic and show growth in fall and winter if placed in a sunny window. In fall and winter, watering should be cut back, but not eliminated. During the summer months, they should be in partial shade.

R. difformis should be grown in a heavier soil mix with good drainage. The plant can flower any time in the spring and summer, although spring is the more common time. The flowers are yellow and large for the size of the plant. When in full bloom, the flowers can completely hide the plant.

This plant may be winter-hardy in our area. It can survive temperatures down to 0 degrees F. According to one plant forum, a person in Moab, Utah, is growing it outside, where R. difformis withstood a winter with 30 days when the temperature never got above 35 degrees, and the low temperatures were near 0.

This area of the country has drier winters than those in St. Louis. If protected from excess winter moisture, chances of survival will improve. The Denver Botanical Garden has Rabiea difformis growing in a south-facing bed next to its cactus and succulent house.

In another forum, I also found a person living in San Francisco growing Rabiea difformis outside in a west-facing rock garden and having no issues. The plant may be able to take more moisture than the experts say.

R. difformis plants or seeds are readily available for purchase on the Internet.