1. Cactus of the Month March 2003 - Crests and Monstrose

In both crests and monstrose plants something has gone wrong with the cellular structure of the growth tip (apical meristem) of the plant. In normal plants the growth tip is a point, and the biochemistry of the plant forces one tip to be dominant or at least locally dominant. In crests genetic mutation removes this dominance, and instead of a single growth tip the area of active cell growth degenerates into a line. In monstrose plants, the chemistry that controls the dominance of one growth tip is missing, so that all potential apical meristems try to grow as quickly as possible (Photo 1a).

Crests and Monstrose growth are often combined with variegation, another mutation of the apical meristem. The three forms are sometimes combined in a single plant. For this month, any combination of crests, monstrose growth, either plain or combined with variegated growth is acceptable. Grafted plants are also welcome.

Crest and monstrose growth are not unique to cacti or even succulent plants. Both are found in many genera of non-succulent plants, including conifers and many common garden plants.

Culture of Crests and Monstrose Plants

Both are grown exactly as normal plants of the same species. Some have weak roots, and only grow well as grafts. However, others are robust growers, and do perfectly well on their own. Careful observation of the health of the plant, and comparison to healthy non-crested plants of the same species will quickly show whether grafting is necessary. Crests tend to be more sensitive to poor growing conditions, getting sunburn quicker, and getting unsightly brown spots more easily than normal plants of the same species. This is one of the many reasons they are often grown as grafts. Monstrose plants are generally more robust (Photo 1b).

For the same reason, they are more attractive to spider mites and mealy bugs than normal plants, and a careful eye must be kept on them to keep good growth.

2. Cactus and Succulent of the Month October 2002 - Variegates

Cuttings of the leaves will root, but will almost always revert to an unvariegated from. On the other hand, normal Sansevierias will often put out a variegated pup. These should be removed from the main plant and grown on their own roots to preserve the variegation (Photo 2a).

Gasteria  - The Japanese have made an art of Gasteria and Haworthia variegate cultivation. Read the 2000 CSSA Journal for just a sampling of the wonderful cultivars. Miniature white species, yellow species, even the occasional pink can be found. There are dozens of variegated Gasterias shown at our shows, and available from all of the local vendors. Look for Gasteria 'Little Warty', a nice white and green species, as well as many of the yellow and green species such as the Japanese hybrid Gasteria 'shozodan', shown above.

Euphorbia  - A number of columnar variegates are available, E. ammak, being the one most often seen. There are also some cristate and monstrose variegates as well.

Agave  - There are several forms of variegated Agave americana. There are forms with a green center stripe and yellow edges, a yellow stripe and green edges, a green center and white edges, a white center and green edges, yellow centers and crinkled edges, random yellow and green banding, and dozens more. Other species of Agaves have also produce variegates, with the same variety of variegation (Photo 2b).

Haworthia  - "Gray Ghost" is a Haworthia retusa variegate. There are several Haworthia limifolia variegates that look as if they were painted with mustard. Offsets are produced on the flower stalks, these are variegated, as are the flowers themselves.

M. Sajeva and M. Costanzo, Succulents, The Illustrated Dictionary
Agave photo by Tom Vermilion

Tom Glavich September 2002

3. Cactus and Succulent of the Month October 2002 - Variegates

Great Variegates

Cacti  - variegates can be found in many genera. Gymnocalycium  are the most often seen, but some columnar variegates and some Ferocactus  variegates are also common in cultivation. The odd variegate appears in many seedling batches. Variegated Turbinicarpus, Astrophytum, Matucana  and Ariocarpus  have been seen at some of recent shows (Photo 3a).

All variegates are mutants. Something has gone wrong with the cellular structure of the leaf or stem growth tip (apical meristem) of the plant. As a result of this mutation, chlorophyll is missing from some or all layers of the plant epidermis.

Variegation is known in most plant families, and variegated plants have a place in most gardens. The bright yellow and white of variegated foliage adds pattern and rhythm to many herbaceous borders. In succulent plants variegates are generally separated from normal plants, and compete against other variegates to put them on an equal footing. Variegated plants grow slower and are generally smaller than non-variegates of the same species. Colored areas are also generally weaker, and more susceptible to fungus, sunburn and other defects. A large well grown variegate of any species is truly an achievement (Photo 3b).

Many of these are artificially propagated by grafts. The famous 'Red Caps' and 'Yellow Caps' are Gymnocalycium  or Lobivia  variegates that have no chlorophyll at all, and live only by being grafted onto a root stock. These are harder to grow well than they appear.

Sansevieria  - There are dozens of named and unnamed varieties. Look for "Bantel's Sensation", Futura, Silver Moon, Silver Princess, and variegated varieties of some of the cylindrical forms. Unlike normal Sansevierias, these can be difficult to grow. They will not tolerate cold and wet conditions. Sansevieria variegates can only be propagated through the tuber.

4. Cactus of the Month March 2003 - Crests and Monstrose

Propagation

All Mutants are unique, so there is no list of recommended species this month (Photo 4a).

The most common method of propagation of mutant plants is vegetative. Cuttings are often grafted to speed growth and to preserve special growth forms (Photo 3a).

Crests and Monstrose plants flower and produce seed, just as other plants do, but less often. Some plants crest as juveniles before they are mature enough to flower and thus remain unable to flower. Good strong growth is probably the best way to encourage flowering but excessively rapid growth can cause some crests to revert to a row of normal heads that may or may not crest again. Monstrose plants generally do not revert due to rapid growth but will occasionally produce normal offsets (Photo 4b).

Photos by Tom Vermilion & Tom Glavich
Tom Glavich February 2003

Mutations are not generally transmitted by seed; however, seed from a mutant plant is much more likely to be a genetic mutant than that from a normal plant. The genetic mutation is more likely to be the same as a parent, but surprises are common.