Part of the Rosette-forming Crassulaceae Project

Kingdom   Plantae
Phylum    Magnoliophyta
Class     Magnoliopsida (Dicotyledons) 
Sub-Class Rosidae
Order     Rosales
Family    Crassulaceae
Genus     Graptopetalum
Species   Approximately 12
A member of the succulent family Crassulaceae (making them relatives of kalanchoe and jade plant though they more closely resemble sedum). Graptopetalum leaves range in colour from waxy green to lovely pink and grey-green. These are cool-tolerant plants which are found natively in Mexico and the American southwest.

These plants produce five-petal flowers which range in colour from white to hot pink and can be speckled, and which grow on long inflorescences. Graptopetalum rosettes will not die after flowering (polycarpic, versus monocarpic).

Graptopetalum grow in upward, somtimes spindly rosettes, and will propagate themselves through the formation of offshoots, also called "pups". In cultivation, the grower would propagate Graptopetalum using stem cuttings (fondly called "decapitation" because the center of the rosette is cut off and potted), or through leaf cuttings.

These plants are fairly delicate, and are not recommended for an inexperienced gardener. They are tricky primarily in their sensitivity to over-watering (even what seems like insignificant over-watering can be fatal). As well, graptopetalum is sensitive to being handled, as skin oil can damage leaves, in particular those with a pearlescent colouration. The leaves are brittle, and relatively heavy for their stems and they fall from the plant quite easily.

COMMON NAMES:

"Ghost plant", "mother of pearl plant" and "jewel-leaf plant".

OF NOTE:

Graptopetalum includes the formerly recognized genus Tacitus, a monotypic genus (tacitus bellus, now known as Graptopetalum bellus or Graptopetalum Tacitus bellus).
CONDITIONS PREFERRED:

Though not as cold hardy as sempervivum, graptopetalum will tolerate frosts. Extended time in temperatures below freezing will kill the plant, and temperatures which may go below 40° (fahrenheit) during extended period should be avoided. As with most Crassulaceae, graptopetalum can tolerate poor soil conditions, so long as it is well draining. Ideally, I recommend 1" - 2" of horticultural charcoal in the bottom of the pot, then a commercial cactus and succulent soil mixture or 2 parts common houseplant soil mixed with one part sand. Bright light is integral to the proper growth of this genus. Plants grown in low-light will grow taller, paler and spindlier than normal and will eventually die due to etiolation. Although bright light is a requirement, heat is NOT. When grown in a hot environment (say, Phoenix), these plants should not be placed in full sun, or the plant will scorch and die.

Allow the soil to completely dry out before watering, and be careful to avoid getting water on the leaves (this is of utmost importance!). In winter, the plants will require less water, as reduced temperature and humidity will induce dormancy. If you are unsure when to water your graptopetalum, watch the lower most leaves for signs of drying and water them then. Graptopetalum is FAR more likely to survive under-watering than over-watering.


PROPAGATION:
As mentioned above, the plant self-propagates through offshoots, and given time one plant will form a dense mat of many. In cultivation, however, it is more common for the grower to use stem or leaf cutting methods. Leaf cuttings are the safest, as you leave the majority of the original plant intact -- if the propagation attempt fails you have not seriously altered the appearance of the mother plant.

Leaf cutting entails cutting a young leaf from near the center of the rosette. Leave the leaf out in the open air for a day to allow the wound to callous over. Dip the leaf into rooting hormone (such as RootOne, which can be purchased almost anywhere you buy plants) and place the leaf (cut-side down) into slightly moist succulent mix potting soil (even better is very lightly moist sand). Soon, a new rosette will grow from the base of the leaf. As soon as enough roots are present to repot, remove the original leaf cutting and repot the rosette.
PRUNING AND GENERAL CARE:

Pruning:
No pruning is necessary except to remove any leaves which have died. This will help to avoid rot and bugs. Avoid touching the healthy leaves of the plant, as your body oils will leave marks.

Tips:
  • Whether grown outdoors or in, these plants are good to forget about. Too much attention by nervous gardeners will kill the plant.
  • When grown outdoors in a wet environment, make sure that the soil is sandy and well-draining. If you aren't careful, your plant will turn to rotten mush.
  • When grown indoors, a standard commercial cactus and succulent soil mixture works well.
  • Make sure you know the characteristics of the species you are growing. Some form flat rosettes and some will form taller and spindlier rosettes. Some species may look etiolated, but it is their normal growth pattern. Get to know your plant.
Problems:
In the event of an unhealthy plant, the first thing to examine is your watering habits. The most common problem is root rot due to overwatering. If the soil is too wet, don't hope it will safely dry out so long as you don't water it for a while. Replace the soil immediately, but be very careful in handling your graptopetalum, it's leaves are very sensitive.

One of the most common pests to houseplants is the mealybug, and your graptopetalum may fall prey to this pest. However, due to the tightly packed leaves, more often than not the mealybugs will attack the roots. This makes them far less visible than mealybugs which attack leaf-stem junctions. The symptoms of a root mealybug infestation is slowed or stopped growth (though in winter this is a normal sign of dormancy). If this occurs without apparent cause, remove the plant from the pot and examine the roots. A white cottony substance on the roots and in the soil is a sure sign of mealybug infestation. Remove all soil and wash the roots gently. Remove any roots which appear damaged with a sharp sterile knife or scissors. Let them dry very throroughly before replanting.

This plant is best grown outdoors and if you live in an area where you only get mild frosts, this is the best option. When potted, these plants are very susceptible to vine weevil. The plant is often used as a bedding or groundcover plant.

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