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.