Marin Master Gardeners
University of California
Marin Master Gardeners

Succulents: little effort, big reward

succulents
Succulents are a low water choice for the garden that asks very little of the gardener. Some succulents contribute colorful flowers, while others add striking foliage or sculptural forms. They may be planted in decorative pots, borders, or in the hard-to-water corners of the garden.

More than 60 plant families include plants with succulent characteristics, distributed among 300 genera and thousands of species. Many come from the arid regions of South Africa, Central and South America, and right here in California. All require the same thing: good drainage, deep but intermittent watering (allow soil to dry out between waterings), bright light/full sun, and good air circulation. They grow best in an open and airy soil that’s relatively low in organic matter. Cold, waterlogged soil presents a challenge for succulents. For this reason, it’s often helpful to plant succulents on a slope or on top of mounded soil.

Succulents are made for water conservation
Succulents require little or infrequent water because they store large quantities of water and food in the spongy tissue in their leaves, stems, or roots, which they release when needed. Those that store water in their leaves often have thick, fleshy leaves covered with a tough skin, such as aloe vera. Plants that store water in their trunk often have small branches and leaves. Cacti are examples of stem succulents: their leaves have been reduced to spines. Other plants store water in their leaves and stems, for example jade plants. Water-conserving features shared by succulents include:

  • Leaves that are cylindrical or spherical in shape, reduced in size, or absent
  • Fewer stomata (the openings in the leaves that allow transpiration)
  • Form of growth that is compact, columnar or spherical
  • Shallow roots to absorb moisture from light rain or heavy dew
  • Waxy, hairy or spiny outer surfaces that create humid micro-habitats, reducing air movement and water loss

Geophytes, plants that die back during part of the year to their bulbs, tuberous roots, corms or rhizomes, are also considered succulents. Amaryllis, bromeliads and hyacinths are example of this type of succulent. Epiphytes, plants that live in the air, unattached to the ground, are succulents that depend on their ability to store water obtained from rain and fog. Some succulents are highly tolerant of salt and other chemicals and can live along the seacoast, in dry lakes or in highly polluted soil.

How to create and maintain a mixed succulent container
Nurseries offer an increasing array of unusual and colorful selections. Many are prime choices for pots. Succulents look fantastic in every type of container imaginable: large seashells, watering cans, baskets, tires, rubber boots, shelving units, wire-wreath forms, teacups, wooden crates, hollowed out logs, old dishes — the list is endless. If you can drill a hole in it to let excess water drain out, you’ve got yourself a container.

Start by looking at samples at nurseries, peruse images online, or check out the large succulent garden at the Falkirk Cultural Center in San Rafael. What do you see? What looks good? Nine times out of ten, what makes a combination sing is contrast — and lots of it. Tiny pea-like leaves make interesting bedfellows with giant spiky leaves. Plump bright white petals look smashing cupping slim upright wands of coral pink flowers. Deep purple tones shine against chartreuse. When it comes to designing with succulents, it’s hard to overdo it with contrast.

Here’s a recipe for succulent success:

  1. Gather a collection of succulents of varying shapes, textures, and colors.
  2. Make sure whatever container you’ve chosen lets excess water drain out. (Drill a small hole at the bottom if it doesn’t.)
  3. Fill container with a mixture of half potting soil and half lava rock.
  4. Plant succulents of different shapes, sizes, textures and colors.
  5. Use small stones or gravel as a mulch on the bare soil.
  6. Place the container in sun or, preferably, where there’s a little afternoon shade. (If your container is indoors, be sure it gets plenty of indirect light, preferably near a window.)
  7. Water when the soil is almost dry. Stick your finger in the dirt to test. Water until the excess drains out. In summer, you may end up watering weekly. Don’t worry if you occasionally forget; your succulents will forgive you.
  8. In winter, move containers inside if possible, or place under eves or other protected area. Many succulents don’t like freezing weather.
  9. When the “pups” start popping out — that is, new baby succulents — share them with friends.
  10. Get another container and do it again. It only takes one time to feel like a pro.

Propagating from cuttings
Succulents tend to reproduce very easily: a stalk, or even a leaf of a plant, may root itself and grow into a new plant. You might want to ask a friend to give you a piece of one of their plants – or a “pup” – a small root-bearing leaf cluster that will grow into a new plant after you pot it.

A dozen succulents for Marin County gardens
Here are some common succulents that are often found in nurseries due to their ease of growing, low-water use, and attractiveness.

Sedum

Sedum
or stonecrop may be used as edging or planted between paving stones or along footpaths. Different types of this popular succulent vary in size and shape from fine-leaved ground covers only 2 in. in height to shrublike border plants, which can be 2 ft. or more. Starry, brightly colored flowers are borne in stemmed clusters in late summer.



Sansevieria


Sansevieria
, otherwise known as snake plant or mother-in-law's tongue, is an undemanding plant, which tolerates low light, high or low heat, and erratic watering. Sansevieria thrives outdoors in a Mediterranean climate and its stiff straight leaves can add welcome contrast to soft, flowering borders.



Aloe
Aloe come in all shapes and sizes from stemless miniatures to large trees. Most are excellent choices for container plantings. Differing from agaves whose leaves unfurl, aloe rosettes are formed as fleshy, pointed leaves grow from the center. Leaves may be banded or streaked with contrasting colors and can become suffused with red in poor soils and arid conditions. Long flower stalks bear clusters of red, orange or yellow tubular blooms. Many species flower in winter or early spring.


Echeveria

Echeveria
is a large genus of succulents characterized by lovely rosettes of fleshy leaves. They reproduce freely by offsets, tiny plants that grow around the edge of the mother plant. One of the most popular is Echeveria secunda, also known as Hen and Chicks. Depending on the species, Echeverias may be green, gray, silver, violet or even rose-hued. They are grown mostly for their foliage, although some species and cultivars develop stalks with flowers that are also quite attractive, for example Echeveria 'Blue Curl.'


Cotyledon


Cotyledon
are shrubby succulents are grown for their handsome foliage and colorful flowers. The stalked, paddle-shaped leaves are borne in opposite pairs forming a compact clump. Flowering usually occurs in late summer and autumn. Flowers are tubular to bell-shaped with curled tips producing copious amounts of nectar that attracts aphids. Easily propagated from cuttings.



Graptopetalum
Graptopetalum (“ghost plant”) resemble echeveria with pointed leaves that form compact rosettes along branching stems. Leaves vary in color from grayish green to lavender pink with reddish margins and are often covered with a powdery film. Plants prefer bright light but may scorch in hot sun. Can be used as ground cover in areas that receive no foot traffic or in rock gardens and hanging baskets.


Kalanchoes



Kalanchoes are succulents with showy flowers that can add a bright splash to the drought-tolerant garden.




Crassula


Crassula
is home to the jade plants, also known as money plants because their thick leaves resemble coins. They can be grown in pots near the front door of the house. According to practitioners of feng-shui, this welcoming plant in the entryway will bring prosperity to the homeowner.

 


Agave
Agave are sculptural plants that bear fleshy, rigid leaves arranged in rosettes, usually with a sharp terminal spine and toothed margins. Once the rosette is mature, which may take many years, an impressive flower stalk emerges from the center bearing creamy white, yellow, or green funnel- shaped flowers. In most species, rosettes die after flowering, leaving the offsets to mature and flower in subsequent years. There are many relatively small agave species that make wonderful design accents in the garden.


Sempervivum

Sempervivum
are small alpine succulents that form neat rosettes of tightly packed, pointed leaves. They are available in a wide variety of forms colors and textures. All spread by little offsets on slender stems that nestle around the mother plant. Small, star-shaped flowers arise on fleshy stems up to 10 inches tall. After flowering, the central rosette dies and offsets live on. Good in rock gardens, crevices in walls and pots. Give plants excellent drainage and light shade in hot summer climates.


Dasylirion

Dasylirion
have thick woody stems that bear clumps of narrow grass-like leaves that shimmer and sway in the wind, creating a dramatic statement in gardens. With great age, some species develop trunks up to 10 ft. tall. Male and female flowers, borne on separate plants, appear along tall spikes in summer and resemble pipe cleaners.

 



Dudleya

Dudleya
are West Coast natives that form low-growing, dense rosettes of ovate-linear leaves with pointed tips. Rosettes may be on prostrate stems or form clumps. Flowers borne on vertical or inclined stems are star-shaped, colored yellow, white or red. Water very little or not at all in summer when dudleyas are dormant; they do most of their growing in late winter.

 


Original articles by Marie Narlock and Barbara Euser for the Marin IJ, and Anne Lowings, Rosemary McCreary, and Sara Malone for the Sonoma Master Gardeners
Edited by Marie Narlock
Photos courtesy of Gardensoft

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