Living stones 3”

Lithops | Living Stones

Native to the dry regions of southern Africa, these small succulents are commonly called living stones because their bodies resemble the rocks and gravel around them in habitat. Almost the entire plant consists of a pair of thick, water-storing leaves separated by a central fissure. Depending on the species, those leaves can be gray, green, cream, brown, rust or pink with windows, dots and intricate patterns across the surface. Mature plants can produce daisy-like white or yellow flowers directly from the center.

These are seasonal plants, and understanding that cycle is a major part of understanding their care. A new pair of leaves develops inside the existing pair each year. The new leaves eventually emerge through the center while the old pair wrinkles, collapses and transfers its stored water into the new growth. Once that process is complete, the old leaves become thin and papery. Established plants can eventually divide and develop multiple heads.

Give them a south-facing window directly at the window or a west-facing window within about 1 foot. Aim for approximately 2,000–4,000 foot-candles at the plant. Foot-candles simply tell you how much light is actually reaching your plant. These are high-light succulents, and insufficient light can cause the bodies to elongate and rise above the soil instead of remaining short and compact.

Under grow lights, use a 5000–6500K full-spectrum light approximately 6–10 inches above the plants as a starting point, aiming for approximately 2,000–4,000 foot-candles at the plant. Kelvin describes the color of the light, while foot-candles tell you how much light is actually reaching it. Keeping the light directly above the plant helps maintain the compact growth these succulents naturally develop.

Watering follows the plant’s seasonal cycle. Water when your plant needs watered. Late summer into fall is generally an active period when plants may grow and flower, and they should receive a thorough watering when they have used their stored moisture, followed by a complete drydown. As winter approaches, a new pair of leaves begins developing inside the old pair and water use drops dramatically. During winter into early spring, the new leaves emerge while the old pair wrinkles and shrinks. Keep the plant dry during this replacement period because the new growth is obtaining water from the old leaves. Once those old leaves have been almost completely absorbed and become thin and papery, watering can gradually resume. During the hottest part of summer, growth can slow again and water use may become very low.

This is why both overwatering and underwatering matter. Giving water during the leaf-replacement stage or repeatedly watering a plant that is not actively using it can keep the root zone wet and increase the risk of rot. But withholding water simply because Lithops are known as drought-tolerant succulents can also leave an actively growing plant without the water it needs. Dry soil alone does not tell you whether to water. Look at the plant, its current stage of growth and what its leaves are doing.

A very gritty, fast-draining mix and excellent drainage allow you to water thoroughly when water is appropriate without leaving the roots sitting in moisture. During an active watering period, slight softening or wrinkling of the established leaf pair can indicate that stored water is being used. That is very different from the old outer leaves wrinkling while a fresh pair emerges from the center. The first can eventually indicate thirst. The second is a normal part of leaf replacement and is a reason to withhold water, not add it.

Success looks like a compact body sitting low in the pot, a healthy new pair replacing the previous leaves, complete absorption of the old pair and normal movement through the plant’s seasonal cycle. The calendar helps explain what is likely happening, but the plant gets the final say because indoor temperature and light can shift the timing. Once you learn to recognize those stages, watering becomes much less about being afraid of giving too much or too little and much more about understanding when the plant is actually ready to use water.