Succulents are popular plants with indoor gardeners. The evolution of water storing capabilities in their roots, stems and leaves helps them withstand drier climates and makes them easier to care for.Last Updated: 04/22
by Adriane Good, MSU Extension Agriculture Agent in Pondera County; Abiya Saeed, MSU Extension Horticulture Specialist
THE WATER CONTENT OF SOME SUCCULENTS
may reach up to 90-95 percent of the plant’s makeup. Often, when breaking open the leaf of a succulent, one can see a moist, fleshy interior, consisting of stored water that is available for the plant when there is none available in the soil.
Succulents have the ability to go dormant, which helps them survive when conditions become too harsh. Because of the severity of their natural growing climates, succulents will flower, pollinate, and develop seed in a much shorter time than many other plants. Succulents are adaptable, durable and can flourish in a variety of temperatures, making them easy to care for and a great option for gardeners in Montana.
A variety of succulents after being transplanted. Photo by Inga Hawbaker.
There are thousands of different plant species that are considered succulents and one of the easier ways to classify them for a home garden is as soft or hardy succulents. Soft succulents are not frost tolerant. These do not do well at temperatures below freezing, and it is important to keep them inside in winter. Hardy, or hard, succulents are more tolerant to colder weather and can survive outside in a Montana winter. Unfortunately, there is no easy way to distinguish a succulent as soft or hardy by looking at it. Succulents suited to zones 6 and higher would be classified as soft. These include succulents within the crassula, echeveria, and sedum families. Succulents suited to zones 5 and lower would be classified as hardy. These include species within the sempervivum, yucca, and lewisia families, which include Montana’s state flower – the bitterroot.
While succulents are lower maintenance than other houseplants, they still have the same basic needs as all plants: water, light, and nutrients. When thinking about succulent care, it’s important to remember that these plants evolved in areas that are prone to infrequent rain but not necessarily extreme heat. Understanding the conditions that succulents are adapted to and utilizing them as a framework to care for them will help plants thrive.
Succulents prefer climates with a low relative humidity (10- 30%) and require good moisture drainage. To approximate their natural environment, succulents should only be watered when the soil/substrate is dry. Once it has dried out from previous watering, additional water should be applied until it runs from drainage holes in the container (if present) or gets completely soaked into the soil. Watering frequently with light sprinkles does not provide enough water for the succulent to survive. Over-watering the plants or planting them in a poorly-draining substrate can stress the plant and may lead to bacterial or fungal root rot. To ensure good drainage, moisten the soil/substrate, and then squeeze it. A properly draining soil will fall apart when let go, whereas a soil that doesn’t drain well will stay clumped together. Purchase soil mixes specifically for succulents, or create your own (utilizing coarse sand, potting mix, and perlite). The choice of container is also an important factor for water drainage. Containers that have drainage holes at the bottom are better suited for succulent plants than those that don’t. If a container does not have a drainage hole, coarse gravel or hydro-stones at the bottom of the pot will help improve drainage. Pots made with certain materials (such as terracotta) will also promote drainage and hold less water than plastic or glass containers.
Succulents also need adequate light, which depending on the plant, can range from 2-3 hours per day for plants with low light requirements, or up to 6 hours per day for plants with higher light requirements. If getting enough light is a concern, place the succulent in a windowsill or near an appropriate artificial light source.
Succulents can benefit from being moved outside during the summer months. If this is done, they should be placed in a semi-shaded area first and then gradually moved to a sunnier location as plants acclimate to the outdoor temperatures and avoid sunburn. Locations that receive hot, intense sunlight from 11 a.m. to 3 p.m. should be avoided. If putting succulents outside, they need to be checked more frequently and will likely require more water.
Succulents do not require as much fertilizer as other houseplants, however, a low nitrogen fertilizer once or twice during spring and summer months can help the plant while it’s actively growing. Succulents will naturally enter dormancy during the colder, darker winter months. During this time, they only need enough water to keep from shriveling. For succulents that spend the winter outdoors, the mixture of cold and wet can be detrimental. They can handle the cold while dormant, but watering during dormancy can be deadly to succulents. To bring a plant into dormancy while it is inside, approximate its natural winter conditions by providing good light, dry soil, cool nights, and roughly 14 hours of dark per day. To encourage the plants to bloom and bring them out of dormancy, gradually decrease the amount of time the plant is in the dark and begin to water it.
Signs of an unhealthy succulent include spindly growth, pale, shrivelled, or dropping leaves and changes in color. Although it is rare, if a leaf is infected with a bacterial or fungal disease, remove the leaf to limit the spread. Bacterial and fungal diseases can be prevented through proper watering and bright light. Scale and mealy bugs may also attack succulents, especially indoors; these can be removed with a cotton swab dipped in 70% rubbing alcohol or insecticide. Succulents are incredibly sensitive during planting because of their relatively small root system. Damaged roots can leave plants susceptible to soil borne pathogens, resulting in disease. If the roots of the plant may have gotten damaged when transplanting, keep the plant out of strong sunlight and don’t water it for about a week to give the roots adequate time to heal.
Succulent plants can reproduce through vegetative propagation. In fact, nearly all nursery-raised succulents are produced vegetatively through leaves and cuttings. Vegetative propagation is much quicker than growing a plant from seed, which can take 3-6 months to germinate and begin to grow. Propagated succulents tend to be more desirable to some because they are genetically identical to their parent plants (where the cuttings were taken from). This way, one knows exactly what plant will result from the cutting.
Propagating a succulent is quite simple. First, cut off a leaf or tip from the stem and then allow the wound to callus or dry. Once it has dried, the cutting can be placed into slightly moistened, sterilized sand. The cutting should be watered sparingly until roots have started to develop. A rooting hormone may speed up the process of root development, but is not necessary. Root formation can be tested by gently tugging the cutting from the substrate. If there is resistance, then the roots have formed, and the plant can be transplanted into another container or a garden and cared for like any other succulent. The best time to take a cutting to grow a new plant is in spring, after the plant’s dormant period. The cutting should be kept short to prevent wilting of the leaf before the new plant can form.
For additional information about specific succulent varieties and their propagation requirements, check out the following resources: