A Guide to Succulents: Types, Care, and Benefits

Succulents are an ever-popular plant choice for outdoor gardens and indoor home decor. They have interesting and unique-shaped foliage in a variety of colors, and many of them flower. They’re easy to grow and can withstand neglect, so they’re a great choice for beginners. If you like the idea of having greenery in your home but haven’t had great success with houseplants in the past, try growing succulents.

As a group, succulents include lots of interesting varieties, and come in all shapes, sizes and colors. They all have fleshy leaves and stems that enable them to store water for long periods of time. Most are native to arid desert regions where they withstand intense sunlight and temperatures, and minimal water. Others grow in humid tropical rainforests, thriving in high humidity and dappled light.

Many succulents are frost-tender and are most often grown indoors as houseplants. They can only be grown in outdoor gardens in regions where winter temperatures stay above freezing. When grown in containers as houseplants, they can be moved outdoors during the warm summer months and brought back indoors before the first frost. 

There are also many varieties that can tolerate temperatures below freezing. These are the frost-hardy varieties that can be grown in the outdoor garden in regions with colder winters.

This article will introduce you to the world of succulents and show you why you’ll want to include them in your outdoor garden design or add them to your indoor home decor.

What Are Succulents?

A succulent is a plant that stores water in its fleshy leaves or stems. Most of them – with a few exceptions – are drought-tolerant and adapted to dry environments.

Succulents are native to a range of habitats, including deserts, grasslands (including alpine areas), and tropical regions. They each have internal biological adaptations to survive their specific growing conditions. These adaptations include differing root systems, water storage mechanisms, and leaf structures. 

Desert succulents have adapted to thrive in harsh environments with extreme temperatures, drought and well-draining nutrient-poor soils. They need low humidity, intense sunlight and infrequent watering. 

They either have deep root systems to seek out water underground or wide-spreading fibrous root systems to capture as much moisture at the surface as they can. Some also grow low to the ground where temperatures are less extreme. Examples of desert succulents include aloes, sedum and most cacti.

Grassland succulents have different adaptations than the desert succulents. They are adapted to more moderate temperatures, in environments with limited, inconsistent rainfall and well-draining, nutrient-poor soils. They have shallow root systems to quickly take up moisture before it’s lost to evaporation. Examples of grassland succulents include Echeveria and Crassula.

Tropical (or Forest) succulents are tolerant of moderate humidity, unlike their desert cousins, and prefer bright filtered or dappled sunlight (or part shade.) They need more frequent – but limited – watering than other succulents and need light, well-draining soil. Many of them are epiphytes, growing in crevices on other plants such as the branch forks of trees, rather than in the ground. They tend to be “understory” plants, growing beneath the cover of taller, denser vegetation. Examples of tropical succulents include hoyas, air plants and Christmas cactus.

For gardening purposes, succulents can be considered as one of two categories: The first is referred to as “cold hardy” (or “frost hardy”) and includes varieties that can be grown outdoors in zones where winter temperatures drop below freezing. This group is also sometimes referred to as the “outdoor” succulents.

The other category is known as the “Frost tender” succulents and includes varieties that can’t tolerate temperatures near or below freezing. They can be grown outdoors only in zones where temperatures stay safely above freezing all year. They are more often grown as houseplants, so this group is also known as the “Indoor” succulents.

Succulents vs Cacti vs Euphorbia

Succulents can be found in many plant families, including Cactacea (all cacti), Crassulaceae (e.g. Jade plant) and Asteracea (e.g. String-of-pearls). These and many other plant families include plants that have evolved to withstand dry conditions, with the succulent’s characteristic fleshy leaves and stems to store water. However, not all members of these families are succulents, with the exception of cacti (see below).

Cacti are their own botanical family, Cactacea. All cacti are succulents but not all succulents are cacti. Desert cacti have no or few leaves and along their stems. Instead, they have small structures called “areoles.” These areoles may be small indentations or small round bumps, where the cactus spines emerge. Areoles are what distinguish cacti from other succulent plants.

Euphorbias also make up their own botanical family, Euphorbiaceae. Their common name is “spurge.” The trait they all share is a milky sap that causes skin irritation and can be poisonous if ingested. Members of this family vary widely. Some – but not all – are considered succulents, and many have features similar to cacti.

Succulent Plant Characteristics

Leaves

What makes succulent leaves unique is that they can store water for extended periods of time. They are thick and fleshy, often with a waxy coating to minimize transpiration (loss of moisture through the leaves). Some succulents don’t have true leaves. Instead, they have flat fleshy segmented stems in which they store water.

In addition to storing water, the fleshy leaves and stems also store nutrients.

This ability to store water and nutrients makes succulents extremely drought tolerant.

Flowers

Some succulents are grown indoors for their attractive foliage (e.g. Snake plant) and rarely flower as houseplants. On the other hand, some varieties such as hoya and Christmas Cactus, are grown for their attractive flowers.

Succulent flowers come in a variety of shapes and colors. As houseplants, they tend to flower less frequently than in their natural habitat but with the right care, they can be coaxed into bloom, sometimes several times a year.

Succulents grown in the garden outdoors produce flat clusters of small star-shaped flowers loved by bees and butterflies. Different varieties flower from spring through fall, providing several months of visual interest.

Roots

Succulents have diverse root structures based on their varied natural habitats.

Some desert succulents have shallow wide-reaching root systems to absorb as much of the infrequent rainfall as they can before it evaporates. Others have deep taproots to access water further underground.

Grassland and alpine succulents are native to regions with sparse but more frequent rainfall than arid deserts. These varieties generally have roots that extend about 6 inches (15 cm) deep into the soil and spread horizontally to capture maximum rainfall.

Tropical succulents are often epiphytes, meaning they grow on other plants, not in soil. Their root systems serve to anchor them into the crevices of trees. To absorb moisture and nutrients from the air, tropical succulents grow long aerial roots from along their stems.

Succulent Growing Conditions

Most succulents – with a few exceptions – are native to hot arid regions that receive little and infrequent rainfall. They have adapted to conditions that are hot and dry, with lots of sun, low humidity and gritty well-draining soil.

There are also a few varieties that are native to alpine regions, including Cliff Maids (Lewesia cotlyledon) and Hens n chicks (Sempervivum tectorum) These are among the cold hardy varieties. 

Then there is the well-loved Thanksgiving cactus (Zygocactus truncatus), often mis-named the Christmas cactus (which is another very similar plant.) This seasonal favorite is native to the rainforests of Brazil, where they grow in the crevices of trees, not in soil. They prefer their growing medium to be kept evenly moist, unlike most succulents that can go long periods between waterings.

Container Choice

One of the most important considerations for growing succulents indoors is the choice of container. It MUST have drainage holes in the bottom to allow excess moisture to drain away. Adding a layer of gravel to a pot with no drain holes will NOT provide proper drainage for any houseplant, but especially not for moisture-sensitive succulents.

Light

Succulents need at least six hours of direct sun to grow well. Indoors, a south-facing or west-facing windowsill is ideal. Plant lights can also be used to simulate sunlight if you don’t have a windowsill that can provide adequate natural light.

Succulents grown indoors benefit from being put outdoors during the summer (their active growing season).They will need to be transitioned gradually to the outdoors so as not to shock with the sudden change in temperature and light conditions. Don’t place your indoor succulents in outdoor spots that get the intense mid-day sunshine. 

Soil (indoor and outdoor)

Whether growing succulents in containers as houseplants or planted out in the garden, the key to success is well-draining soil.  If the soil retains too much moisture, you’ll find your succulents will quickly succumb to root rot. 

For succulents grown in containers, use a potting mix that contains plenty of gritty material such as coarse sand or perlite. Commercial potting mixes labeled specifically for succulents or cactus are best. Avoid mixes that are mostly peat moss or coconut coir. 

You can also make your own potting mix by blending equal parts regular potting mix and coarse sand or perlite.

In the outdoor landscape, choose locations that have good drainage and gritty soil. Succulents are great choices for rock gardens or landscapes with naturally sandy soil. 

Watering

The most common mistake of succulent care is over-watering. Most succulents are drought tolerant and need infrequent watering. Too much moisture will quickly lead to root rot.

There are a few exceptions to the rule, though, so always check the needs of your specific variety.

Succulents need regular watering during their active growing season (spring and summer). In winter, indoor plants go through a resting period and need far less frequent watering.

Container plants should be watered when the soil is completely dry. Then the container should be given a thorough deep watering. Add room-temperature water to the soil surface slowly, a little at a time, until it starts to flow out the pot’s drainage holes. This way you know the soil through the whole pot is well-soaked.

Succulent Propagation

Succulents are some of the easiest plants to propagate. They can be grown from seed, although it can be challenging. Instead, they’re most often propagated from pieces of existing plants, a process known as vegetative propagation.

Vegetative propagation of succulents can be done using different parts of the plants:

• Leaf cuttings
• Stem cuttings
• Offsets or plantlets 

Which method you choose to use will depend on the variety of succulent. Leaf cuttings work best for varieties with distinct fleshy leaves like Jade plants or echiveria. Stem cuttings are easier for upright or spreading succulents like sedums.

Leaf Cuttings

Leaf cuttings are complete leaves that have been removed from the parent plant. To remove a leaf, hold it between your thumb and forefinger and gently twist it until it snaps off. After the leaf is removed, it is left to callus off  (form a dry skin over the cut) before being planted.

The leaf cutting method is good for plants that have distinct individual leaves such as Jade plant or Echeveria.

Stem Cuttings

Stem cuttings can either be taken by cutting off the growing tip of the stem or a whole stem may be cut into smaller pieces. Each of these pieces should have several leaves attached. Two or three leaves are kept on one end and the rest of the leaves removed.

The stem cutting method is good for succulents that have grown tall and “leggy” with a cluster of leaves at the top of a bare stem.

Offsets/Plantlets

Many varieties of succulents naturally multiply themselves by growing new plants (or offsets) around the base of the original plant. Others grow tiny new plants (plantlets) along the edges or at the tips of their mature leaves.

When offsets grow at the base of the mature plant, they develop their own roots and can be separated (divided) from the parent plant and planted directly into fresh soil.

Plantlets that grow from the tips and edges of leaves on the mature plant will often develop aerial roots.The plantlet can then be gently removed from the mature leaf and planted with their aerial roots in soil. Sometimes the plantlets will naturally drop off the leaves onto the soil below where they eventually root into the soil. 

 Why Grow Succulents?

There are many benefits to growing succulents, especially indoors. They are a great choice for beginners because they’re so low maintenance and don’t need frequent watering. They can tolerate a lot of neglect!

They have plenty of other benefits too:

• Lots of different sizes, leaf shapes and colors for indoor and outdoor designs
• Pest-resistant in the outdoor garden
• Improve indoor air quality
• Some have medicinal properties (e.g. aloe vera, yucca)

There are so many different types of succulents, both for growing indoors as houseplants or outdoors in the garden. Some stay under 12 inches (30 cm), while others in the garden can grow to several feet (meters) tall. Their foliage can be deep green or pale green, bluish-grey or shades of purple, pink and orange.

Most succulents, grown indoors or in the garden, are pest-resistant. Cacti with their spines and members of the euphorbia family with irritating milky sap aren’t very tempting for animals to nibble.

A study released by NASA in 1989 found that several varieties of houseplants can contribute to improved indoor air quality by absorbing chemicals such as formaldehyde. The succulents Aloe vera (Aloe barbadensis) and Snake plant (Sanseveria sp) were two of the plants they studied.

Many succulents are toxic to people and pets but others have potential medicinal properties. Aloe vera is well known for treating skin conditions as well as an internal treatment for digestive issues. Certain species of Yucca are also known to have many potential health benefits, including support for the immune system and easing pain associated with arthritis.

Popular Varieties of Succulents

There are so many interesting and attractive succulents to choose from. Some are cold hardy and can be grown outdoors in the garden in regions where the temperatures don’t get colder than a few degrees below freezing.

Others are frost tender and can only be grown outdoors where temperatures stay well above freezing all year. Otherwise, these varieties are grown indoors as houseplants .

Here’s a list of some of the popular succulent varieties you may have seen growing in your local gardens or for sale at garden centres.

Cold Hardy (Outdoor)

Garden Sedums: There are lots of different sedums (aka stonecrops) to choose from for the outdoor garden. Some grow tall, like Sedum telephium ‘Purple Emperor’ It has deep purple fleshy leaves and grows up to 2 feet (60 cm) tall and wide.  It produces umbrella-shaped bunches of small pinkish-white flowers that bees love later in the season.

Others grow more like ground cover, such as White sedum (Sedum alba). This one has green fleshy foliage that develops reddish tinges in the fall. It has white flowers in summer.

Yucca: There are dozens of different types of yucca and many – not all – of them are hardy down to about 10 degrees F (-12 C). They can grow anywhere from 3 to 15 or more feet (1- 4.5 m) tall. They have long spiny leaves so it’s best to plant them well away from walkways or patios. Also, their root systems can be invasive, so yuccas shouldn’t be planted near buildings or sidewalks.

Hens n chicks (Sempervivum tectorum): This sedum grows its pointy-ended leaves in a tight rosette. It self-propagates by growing many small new plants (offsets) from around its base (hense its common name hens n chicks). It’s a great choice for sunny dry garden spots with poor soil.

Prickly pear cactus (Opuntia sp): There are many varieties of prickly pear cactus. It’s the state plant of Texas, where several varieties can be found. Two cold-tolerant varieties are the Plains prickly pear (Opuntia polycantha) native to North America, and the Eastern Prickly pear (Opuntia humifusa) native to the Eastern US. Both of these are hardy to USDA zone 4.

Prickly pear cacti vary in size from the 12 inch (30 cm) O. humifusa to the 15-foot domesticated-crop variety Opuntia ficus-indica (Cactus Pear). They all have broad, flat, edible green pads with white spines. Their yellow flowers are followed by an edible red fruit. 

Frost Tender (Indoor)

Aloe vera (Aloe barbadensis): This tropical succulent commonly grown as a houseplant is well known for the medicinal and cosmetic properties of the gel in its thick fleshy leaves. The long narrow fleshy leaves can reach 18 inches (45 cm) long and grow in a dense rosette. They are grey-green and have small white spines like teeth along the margins.

Jade (Crassula argentea or C. ovata): This familiar succulent has glossy dark-green spoon-shaped fleshy leaves. The leaves grow directly from a tree-like trunk. It’s commonly grown as a houseplant, reaching a size up to 3 feet (90 cm) tall.

String-of-pearls (Senecio rowleyanus): This is a popular houseplant sought-after for its unique foliage. The silvery-grey pea-sized leaves grow tightly along trailing stems, giving the plant its common name. It can be grown in a hanging basket or in a pot and left to trail over the sides.

Air plants (Tillandsia sp): Air plants have become a popular fixture of the houseplant market. They’re easy-care and unique-looking, suitable for all sorts of decor schemes. You’re sure to see them in garden centres and houseplant outlets displayed in hanging glass globe terrariums, attached to pieces of driftwood or even glued to seashells.

They’re native to tropical and sub-tropical areas of North and South America, including some US states like Florida, California and Texas. 

Instead of growing in soil, they grow roots to cling onto other plants, like tree trunks or branches. Some even grow on cacti in the desert. They can also cling onto rocks or even buildings. They don’t get any nutrients or moisture through their roots. Instead, they absorb all they need from the air (hence their common name), through specialized growths (called trichomes) on their leaves.

Air plants grow in a rosette of long leaves that form a wide bulb at the base and get thinner towards the tips that are often curly. Many of them look like silvery squids with lots of tentacles, while others are flatter and fan-shaped.

Snake Plant (Sansevieria sp): This popular houseplant seems to break the general rules of succulents. Its tall sword-shaped leaves are dark green and leathery but  aren’t as fleshy as other succulents. In addition, it can tolerate low-light conditions. Like other succulents, it can go long periods between waterings.

Christmas cactus (Schlumbergera bridgesti) Thanksgiving cactus (Zygocactus truncatus) and Easter cactus (Rhipsalidopsis gaertneri):  These three cacti are very similar-looking and easily confused. They all have flat segmented stems with pointy edges on each segment. Their flowers, in shades of white, pink or red, grow from the stem tips.

They get their common names from the time they come into bloom. Most people will be familiar with the name “Christmas cactus”, but it’s usually mis-named. The flowering plant available on the market from late November through January is actually the Thanksgiving cactus. The true Christmas cactus, Schlumbergera, isn’t as readily available for sale because it blooms too late for the traditional Christmas season.