cultivation Calibanus hookeri (Mexican Boulder)

Who can provide us with info about the cultivation of Calibanus hookeri (Mexican Boulder)? We are located in South Africa in a winter rainfall area. Well drained loamy, sandy soil and climate zone 10a (no frost in Summer temperatures occasionally between 100 and 110 degrees F (40-45 degrees C.).

We have at the moment about 40 seedlings in a tray and these already start to make a caudex.
One of the questions is how long it will take before it has a caudex of around 20-25 cm? We will plant the majority outdoors in an acre and a minority in pots under cover.
We grow the plants in the gardens and in the nursery fully organically.

Thanks in anticipation for all the help.

Herman & Yvonne

 

I have one that is about 2 years old, in a container, and the caudex is about 6 cm in diameter. However, my growing season is about 4 months, whereas yours is likely longer and hopefully, you will have a raised bed or field where you can grow them.

Philippe de Vosjoli, in his book Pachyforms, A Guide to Growing Pachycaul and Caudiciform Plants, p.263...."Full or partial sun and summer heat are required for growth but generally this is a tough plant, tolerant of many errors in cultivation. Grows fastest when raised in beds as this species produces a large amount of root and easily becomes potbound. Young plants grow with most of the caudex buried and should be allowed to remain this way for many years if your interest is in having a large plant. If lifted early, the caudex will grow very slowly, but will develop early on the bark fissures that make this species so appealing. Personally, at least for the first ten years, I'd focus on getting this species to put on size rather than character. C. hookeri will survive brief light frosts. Needs some regular grooming to look its best, including removal of old dried leaves. Plants should be watered regularly when in growth, and less frequently during the cold months."

So, to answer your question regarding size, there are many variables. However, it appears that if field grown, given heat, and the caudex remained buried, it will grow fastest.

Mark

 

Thanks Mark,

Our growing season is from October to June (Souther Hemnisphere). Hopefully we have nice caudexes in 2-3 yrs.

Enjoy Life in West Michican

Yvonne & Herman