While a student at the New York Botanical Garden in the School of Professional Horticulture, I had the great privilege of interning in the greenhouse which keeps the NYBG collection of desert plants. I re-potted, propagated and generally cared for succulents and other desert plants from all over the world. Among the collection were so many of the succulents which are popular today – Haworthia, Gasteria, Sansevieria, Echeveria, Dracaena, cacti and Kalanchoe to name a few.
The word ‘succulent’ is derived from succus - meaning ‘juice’ or ‘sap’in Latin. An overarching characteristic of succulents is their ability to retain water in their tissues allowing them to withstand extreme conditions. Because water loss via transpiration will cause most plants to fail eventually, it is this water-storing capability of the stems, leaves and roots of succulents which make them survivors.
I came to love and appreciate so many of these prickly plants. I am thrilled to see that succulents are so popular, but not surprised to hear that some find them difficult despite the promise of no care and no watering needed. Although succulents are found practically all over the world and in a variety of climates, sometimes they do not thrive indoors. Once pet succulents begin to fail as houseplants, it seems they are frequently discarded. Let’s look at some problems we might encounter with succulents as houseplants.
As with most houseplants, soil, water, temperature and light are key for success. Succulents are no exception. Understanding the watering needs of succulents is frequently a problem. Light exposure for succulents – intensity and duration – is also an important consideration for the health of succulents. Proper ambient air temperature is also important.
Soil
Many succulents on the market today come from hot, dry desert climates. Not all, however, so it’s important to do a little research on your succulents to determine any special soil requirements. Overall, it’s safe to say that most succulents thrive in an aerated, fast-draining soil with ample pore space between soil particles. I see many succulents for sale potted in regular potting soil with a lot of peat. This is not ideal for succulents so plan to re-pot these plants when you bring them home.
Most manufactured cactus potting soils are fine but look at the content label before buying. You will want a mix that provides porosity – like sand, perlite, or pumice. Other items in the mix, like compost or bark, should be moderate to coarse sized particles. This will allow for water to move quickly around the roots and through the soil.
Water
It is true that many succulents require infrequent watering and in small amounts. They generally do not like to sit in soggy soil or have retained water in the plant container saucer.
Some succulents, like cacti, form roots under dry conditions as they search for water. Over-watered plants and water-logged soil are the main reasons for failure of indoor succulents. Retained water in poorly draining soil will eventually cause roots to rot, and edema (brown or rusty spots) on plants stems. Once roots begin to rot, it is difficult to rescue the plant.
When you do water your plants, bring them to the sink so that excess water will drain away. I was taught to water cacti and other succulents so sparingly that only one drop of water drains from the bottom of the pot
Temperature
As mentioned previously, succulents exist in a wide array, native to a variety of climates. Most succulents purchased as house plants require relatively high temperatures to thrive. If the temperature in your home fluctuates frequently, this might not be an optimal environment for your succulents. If your potting soil doesn’t drain well and the ambient temperature is too chilly, retained water in the soil will cause the plant to rot.
Light
Light is essential for plant health and growth. Being autotrophs or self-feeders, plants produce their own energy or food through photosynthesis. Light is an essential part of that process. Your succulents likely are native to an environment with intense sunlight. As houseplants, if your succulents sit on a windowsill shaded by a tree, they will likely fail to thrive. As well, if the plants sit in scorching sun, say above 90 ̊F, amplified by the window glass, with no movement of the ambient air, leaf scorch may occur. The good news is that you can easily regulate the amount of light by providing supplemental lighting with plant lights. Your plants may require 14-16 hours of sunlight to grow and produce flowers.
Love Those Desert Plants!
There are so many intriguing features to discover about succulents –adaptation to water loss, metabolic intricacies, protective devices like spines and contractile roots, and other biological adaptations. Succulents provide a stunning array of flowers, plant shapes and sizes. They are found throughout the world in deserts, chaparrals, dry woodlands, high altitudes and in humid tropical regions. One of the most intriguing plants are the Copiapoa cacti of the Chilean Atacama Desert. Situated along the Pacific coast, the Atacama Desert is probably the driest place on earth. It is thought that the Copiapoa cacti take in minute amounts of water which collects on their spines from occasional fog. These plants thrive in this climate; vast areas of the Atacama are covered with the Copiapoa.
Plants of the desert are so fascinating. You will enjoy learning about your succulents and their native environments. Following guidelines for proper soil, watering, temperature and light will yield great results. Perhaps your succulents will flower. Succulent flowers are stunning!
