Friday, September 2, 2011

Haworthia reinwardtii: Discovering a Problem

Fig. 1    Haworthia reinwardtii

A year ago during our trip to Southern California, we visited some friends in Oxnard. They gave me this interesting plant (Haworthia reinwardtii) (Fig. 1) already with five offsets. I thought that I'd wait for it to grow some more before repotting. Flowers (Fig. 2) came out on long spindly spikes twice during that time. A few leaves grew on top of the neatly stacked arrangement - adding more height to the offsets. For plants like this, production means the appearance of new plants in the form of offsets. However, no new offsets appeared. The plant was moved to different places in the yard to compare how it would perform under different conditions. The plant grew minimally regardless of the location. 

 
Fig. 2  Flowers of Haworthia reinwardtii

Observations.  The color of the leaves (Fig. 3) changed with light intensity and soil moisture levels. When exposed to more sunlight the leaves turned reddish and when the plant was in the shade the leaves turned back to green.  The leaves also developed a yellowish tint when water was withheld for an extended period of time.  The lack of moisture generally slows down photosynthesis which consequently results in reduced chlorophyll production.

The leaves (Fig. 3) of this plant are very hard and crusty - they remind me of armadillos.

Fig. 3    Leaves

Shocking Observations. I've waited too long - I could not wait for a substantial growth to happen on this plant anymore. So I decided to do a deeper investigation into this potted plant. It was surprising to find out that the plant was growing in pure sand (Fig. 4). If there was any other material in the pot it was only a few dead roots. The poor plant was living in an almost inert material. It appears to me that whoever planted this plant was more concerned about drainage than nutrition. One thing became very obvious - the plant can withstand extremely poor soil conditions. However, for optimum growth, the essential elements have to be provided to the plant. This is probably the reason why the plant failed to multiply.
Fig. 4  Sand

Solution to Problem.  The plants were repotted into five individual plants.  New potting soil with considerable amount of organic matter was used.  They are currently being held under the shade of a tree while recovering from the transplant shock.

Expected Outcome.  In the new potting soil, it is expected that the plants will respond to the nutrients present in the soil.  New offsets might begin to appear at the base of each plant.  Dividing the plant allows more room to for each plant to grow. 


When plants are not growing normally it it likely that it is deprived of something - soil nutrients, water, sunlight, or air.

9 comments:

  1. Oh no. Poor Haworthia. Your post is timely, Helen. I just acquired new succulents two days ago. I have yet to repot so I will make sure they get enough organic material in the potting medium.

    ReplyDelete
  2. Was looking on PlantZAfrica but they only have two other Haworthia species. In South Africa these little succulents are sold in sharp draining gravel. Will be interesting to hear how your little plants grow. They do grow slowly however.

    ReplyDelete
  3. And a PS - from our winter rainfall mediterranean climate. Prefer a little shade. Plant in sharp sand.

    ReplyDelete
  4. All your due diligence with the plant will hopefully get it back on tract. I am unfamiliar with this one, but good luck.

    ReplyDelete
  5. Looks like a fascinating succulent plant. Good luck with the experiment!

    ReplyDelete
  6. Amazing! It's a tribute to the plant that it managed to not only bloom (initially) but produce offsets in this condition. I'm anxious to see what they all look like a month from now!

    ReplyDelete
  7. This comment has been removed by a blog administrator.

    ReplyDelete
  8. A lot of people grow these in a mix with little organic matter, but sand isn't optimal. Usually one would use something like 70% pumice / 30% compost.

    ReplyDelete