Succulent Plants: An Overview
Succulents are surging in popularity because they are low-maintenance, low-water and cool to look at and collect. They grow well in containers and add year-round color and interest to frost-free gardens. Neglect them, and chances are they’ll be fine. But your succulents will be more lush and will grow faster if you give them regular water, good soil, and bright but not harsh sunlight.
The succulent plants listed here are popular with designers and are readily available (or becoming so).
Note: The photo that accompanies each is one example; other species will look different.
Aeonium — Rosettes typically resemble big, fleshy-petalled daisies. Colors include green, yellow and garnet. Leaves of Aeonium ‘Sunburst’ are striped with yellow or cream. Aeonium ‘Zwartkop’, another show-stopper, is magenta-black. There exist many hybrids (like the Aeonium urbicum hybrid shown here). Some species are shrub-forming; all produce rosettes at the tips of ever-lengthening stems. Frost tender.
Agave — These rosette-shaped succulents are native to the Americas. There are dozens of species of agaves, including many that are small and beautifully suited to pot culture. Agave victoria-reginae is a favorite; it grows to the size of a soccer ball over time. With the notable exception of Agave attenuata, most agaves tolerate temperatures into the mid-20s F; some—such as Agave parryi ‘Truncata’ shown here—go much lower.
Aloe — Dramatic flower spikes, mid-winter through spring, are hot hues of orange or yellow. This photo shows aloes in bloom at the Huntington Botanical Gardens in January. Gel-filled, tapered and serrated leaves of many aloes form starfish-like rosettes. Species range from a few inches in diameter to tall trees. Aloe arborescens, a common garden plant throughout Southern California, is an excellent fire-retardant succulent for wildfire-prone areas. Frost-tender.
Cactus — This general category refers to succulents—usually from desert climates—with spines, which are modified leaves that radiate from central points (aureoles). Some are columnar, others round or have pads. Small cacti suitable for pots have a huge following with collectors. Do consider using golden barrels (shown here) in your succulent garden; they are an unmatched textural enhancement. Many but not all cacti tolerate some frost.
Crassula — There are two main forms: branching and stacked. I chose a stacked crassula (Crassula perforata) to show here, but there are many lovely and unusual shrub-forming ones. Plain jade (Crassula ovata) is quite common; others are silvery gray, bright yellow, and variegated cream-and-green—often with red margins. Use jades as mounding shrubs and grow stacked crassulas, which are great cascaders, in terraces and hanging baskets. Frost tender.
Echeveria — Those with tight rosettes tend to form hen-and-chicks clusters. Echeverias that resemble cabbages usually grow atop ever-lengthening stalks. Ruffled varieties like those in the photo are among the showiest of succulent plants. All are ideal for containers, in fact, I discourage people from growing echeverias in garden beds as the leaves are easily marred. Echeveia subrigida is among those that tolerate a few degrees below freezing.
Euphorbia — This immense genus includes many nonsucculent plants; all have in common a milky sap that can be irritating, even toxic. Columnar species such as Euphorbia ingens suggest statuesque cacti. Unlike cacti, which have satiny flowers, those of euphorbias are beadlike. Designers like Euphorbia tirucalli ‘Sticks on Fire’ (shown here) which turns brilliant sunset hues. Droll Euphorbia obesa is a spherical succulent plant with subtle herringbone stripes. Frost tender.
Haworthia — These windowsill succulent plants, which seldom get larger than a softball, thrive indoors and do well in pots. I don’t recommend growing them in the garden as they readily sunburn and might be stepped on. Besides, it’s a shame not to enjoy them close-up. Haworthias are easily hybridized—a hobby enjoyed by enthusiasts worldwide.
Ice plants — These groundcover succulents have brilliant blooms; few sights can compare to a hillside massed with iceplant flowers. Ice plants need no mowing, require very little maintenance, and once established keep weeds at bay. Ice plants would make ideal lawn substitutes if they could tolerate foot traffic. But you can grow ice plants on steep, rocky slopes, something not possible with a lawn.
Kalanchoe — These succulent plants are prized for their colorful or felted leaves and their flowers. Kalanchoes come in a variety of shapes and sizes. Most common is Kalanchoe blossfeldiana (shown here), which is sold in supermarkets; numerous hybrids produce long-lasting blooms in crayon colors. Surging in popularity is Kalanchoe luciae; its paddle-like leaves are sometimes wavy, and turn from teal to bright red when grown in full sun. Frost tender.
Sedum (stonecrop) — These trailing succulent plants with stacked and concentric or bean-shaped leaves produce masses of star-shaped blooms in summer. Plant sedums in rock gardens and use them as fillers for containers and as ground covers. Unlike other genera of succulent plants, most sedums (especially smaller ones) prefer cool summers and winters and tolerate temperatures well below freezing.
Sempervivum (hen and chicks) — Like sedums, sempervivums are cold-climate succulent plants; they do not do well outdoors in the heat of a Southwest summer. Semps resemble echeverias but rosettes have thinner, pointed leaves and a more compact, spherical form. Most produce offsets that create appealing clusters. Tuck sempervivums into the niches of a rock wall and let them overflow the openings of a strawberry jar. Frost-tolerant.
Senecio — Groundcovers Senecio mandraliscae and Senecio serpens form drifts of blue and are striking juxtaposed with red- and orange-leaved succulent plants (such as Aloe cameronii or Euphorbia tirucalli ‘Sticks on Fire’). Let Senecio rowleyanus (string of pearls), which has pea-like leaves, cascade from a dry fountain or birdbath; it’ll suggest droplets of water. Most senecios will tolerate a few degrees below freezing.