Gardening 101: Lithops

Lithops, The Living Stone Plant

Lithops is not your standard houseplant. When a non-gardener friend recently asked for help to select houseplants for her apartment, I fully expected we would purchase some standard fare, a virtually un-killable Sansevieria, perhaps, or a Dieffenbachia or maybe a Philodendron: all reliable, if not terribly exciting, indoor growers.  Instead my friend surprised me at the plant store, her attention riveted on a tiny succulent remarkable for the fact that it doesn’t even look like a plant. Lithops is a short, fleshy, dwarf perennial that resembles the rocks it grows among in its native habitats in South Africa and Namibia.  It is cone shaped, tubby, and subtly colored; it could be mistaken for a very wide pencil eraser with an odd cleft, like a mail slot, in the middle of it.

Is lithops the best succulent for you? Read on to learn everything you need to know to grow and care for this unusual plant nicknamed “The Living Stone.”

The stem on a lithops plant is so short as to be invisible and it doesn’t appear to have any leaves, although, guess what, that pencil eraser part is the leaves… two of them. And the cleft is where the next two leaves will emerge. This plant is a model of anti-excess. When the new leaves appear, the old pair shrivel up and drop away. Because it is native to arid areas that frequently receive less than two inches of rainfall per month, Lithops is brilliantly adapted to conserve moisture.  The leaves function as water storage tanks and can sustain the plant through times of extreme drought.  Amazingly, for a plant so spare in its design, Lithops is actually a reliable and rather showy bloomer.

Starting when a plant is from three to five years old,  it will produce spicy scented white or yellow daisy-like flowers, which will emerge from its cleft in the early fall (just before its next pair of leaves appears).

Cheat Sheet

• Show off your Lithops by planting them in shallow dish containers 3 to 5 inches deep to accommodate their tap roots. Top dress with gravel or the stones which the plants resemble.
• Avoid planting Lithops in terrariums as they contain too much humidity for these dry climate natives.
• Do not remove deteriorating old leaves as the plant is still drawing moisture from them. They will eventually fall away on their own.
• Never allow Lithops to freeze.

Keep It Alive

• Lithops are sun lovers but can be burned by too much direct sunlight. Plant in a location that ideally gets 4 to 5 hours of direct sun in the morning and partial shade in the afternoon.
• Use a freely draining succulent soil mix.
• Good air circulation will help to keep your Lithops healthy.
• Do not ever allow the plant to be surrounded with soaking wet soil which will lead to rot and certain death.
• Allow Lithops to dry out between waterings and be vigilant about following the prescribed seasonal watering schedule (see below).

As a survivor of punishing climates, Lithops grown as garden and houseplants require a very particular annual watering regimen.  Water regularly in the spring when the old leaves have finished drying up and also in the late summer and early fall when the plant is flowering and producing a new set of leaves. Watering should decrease dramatically in the peak of summer heat when the plant is dormant and in winter when the plant is drawing moisture from the old, deteriorating leaves.  There is some disagreement on how much less water is needed.  Some experts advise allowing the plant to become bone dry between waterings while others suggest that enough moisture should be added to keep the tiny root hairs on the plant’s tap root alive.  If you choose to grow this plant, be sure to carefully study the moisture requirements for your particular variety.

In the wild, this plant avoids the effects of harsh weather and evades predators by growing so close to the ground that much of it is actually subterranean.  It has developed an ingenious method of allowing light into the plant for photosynthesis. The wide tops of the leaves have transparent cells that allow sunlight to penetrate the inner, underground portion of the leaf.  So not only are its leaves distinctively colored and marked, they are also windows, marvels of engineering for survival.

N.B.: See more of our favorite succulents (and other friendly houseplants):

• Succulents 101: A Field Guide for Planting, Care & Growing.
• 5 Favorites: Mini Houseplants for Apartment Living.
• Everything You Need to Know About Succulents.
• 9 Secrets to Growing Succulent Plants Indoors.