5 succulents to consider planting in your garden
As fall approaches, Autumn Joy comes to mind.
In truth, the plant known by this name begins to bloom in summer but is distinctive among succulents in flowering through the fall season. Domed flower clusters in pink, burnt orange or red – and up to six inches in diameter – hover above round, blue-green leaves. Flowers fade to an attractive dark brown and will hold their form throughout the winter.
As a member of the stonecrop or Crassulaceae family of plants, Autumn Joy, a Sedum hybrid, does not ask for much. Stonecrop refers to a capacity to grow out of stones or rocks, a characteristic especially evident among Sedums. Crassula means “thick” in Latin and refers to the thick, watertight foliage belonging to members of the family. In addition, they share a metabolism common to other dry climate plant groups, as well as to epiphytes (tree dwellers) such as orchids and bromeliads, that can go long periods without water.
Whereas the vast majority of plants have stomata or leaf pores that open during the day, stonecrops keep their leaf pores closed during the day and open them at night. This helps them survive droughts since plants that open their leaf pores during the day lose water through these same pores and are more susceptible to drought stress.
It is important to keep in mind that plants are autotrophs, meaning they manufacture their own food. In order for this to happen, leaf pores must open up and take in carbon dioxide. But there is a trade-off since when these pores open, water escapes and, in dry weather, leaves may wilt. Photosynthesis is a series of biochemical reactions that combine carbon and oxygen from carbon dioxide (taken in through leaf pores) with hydrogen (in the water taken up by roots) to produce carbohydrates, the sole food and energy source of plants. Plants need light (the “photo” in photosynthesis) since it is light energy that splits water molecules into its component parts of hydrogen and oxygen. While the hydrogen in water assumes its role as a building block of carbohydrates, the oxygen in water – sometimes called the waste product of photosynthesis – exits through plant leaves; this our sole source of oxygen and without it we could not survive.
An aside: As indicated above, plants are autotrophs, meaning they manufacture their own food. What we call “plant food” or fertilizer consists of minerals whose elements – especially nitrogen, phosphorus and potassium – make photosynthesis possible. Such elements are constituents of pigments and enzymes that are vital to the biochemical reactions in the photosynthetic process.
It sometimes seems that gardeners belong to one of two groups: Those who like succulent plants and those who dislike them. Succulents are especially popular among beginning gardeners because they are easy to grow and propagate. Succulents are designed for people with little time or money to care for plants, or for those with an appreciation for sculpture, of which cacti. stonecrops, and many other succulents are living examples. People who don’t like succulents complain that they grow too slowly, that their bloom time is too short, that there is nothing lush or dynamic about them. Finally, gardeners are a rebellious lot and may not be interested in plants, such as succulents, that are not necessarily a challenge to grow.
Yet one thing is certain: Until you have seen massive and diverse succulent displays, such as those at The Huntington’s botanical gardens in San Marino, you have no right to pass judgment on these plants. Admission to The Huntington is free on the first Thursday of each month. You will need to make reservations in advance beginning the last Thursday of the month for the following week. Visit huntington.org for complete details.
I have a few favorite species among some of the stonecrop genera that you might wish to consider planting in your own garden or containers, as follows:
Sedum. Other than Autumn Joy, you may want to consider pork and beans (Sedum rubrotinctum) whose leaves are shaped like jellybeans and turn reddish bronze. While acceptable as a ground cover, this species excels as a subject for container growing. Sedum nussbaumerianum is unique in being the only succulent – to the best of my knowledge – with orange leaves. Sedum confusum is the ground cover of my dreams and might be of yours. It grows quickly, but is not invasive. It smothers most weeds. Its roots hold the soil well, but it can be removed permanently with a gentle tug. When you come upon Sedum confusum for the first time, you will want to touch it to make sure its luminescent leaves are not made of porcelain, jade or glass. If I had to gaze at a single plant for all eternity, I might choose this sedum. It is the essence of serenity, spreading smooth and green over the earth. It reminds you that a bench is an essential garden appurtenance; without the means of sitting back and leisurely enjoying your garden’s beauty, why have a garden at all?
Kalanchoe. Flapjack or paddle plant (Kalanchoe thyrsiflora/ luciae) has large, distinctively shaped leaves with a strong infusion of red along their upper margins. while their prevailing green color may turn a chalky blue. This is a species that begs to be grown in containers where it can be viewed regularly at close range; its colorful and whimsical presence is a source of unparalleled ocular delight. Copper spoons (Kalanchoe orgyalis) is a standout species with bronze leaves and yellow flowers. Flower dust plant (Kalanchoe pumila) is a ground cover that features long-blooming pink flowers against a backdrop of downy gray foliage.
Echeveria. The foliage of Echeveria ‘Afterglow’ may be described as lavender in color, yet it has pink and blue and violet and even gray in it. The oversized rosettes are pleasantly soft to the touch and the bright orange to red flowers complete the profile of this highly memorable succulent.
Aeonium. Each leaf of Aeonium ‘Sunburst’ has a broad, spatulate green center with rounded, golden yellow bands on either side, circumscribed by leaf margins tinged with pink.
Dudleya. The various species in this genus, many of which are California natives, referred to collectively as chalk liveforevers, are definitely stonecrops as they may be found growing in cracks of vertical rock faces. Waxy gray to blue-gray foliage has the form of a rosette, which should rot be watered overhead since moisture that settles in the tight crevices between its leaves may overstay its welcome and cause the plant to rot. To irrigate, soak the soil around it. Six species of Dudleya are for sale at the Theodore Payne Foundation (theodorepayne.org) in Sun Valley; five of them are available in 3-gallon containers.
California native of the week: There are more than 30 species and subspecies of Sedum native to California. From everything I have seen, these species have diminutive leaves that may be red, blue, gray, or green. They are so small and slow growing that a flower pot environment would probably be the best for them. For example, Pacific or cascade stonecrop (Sedum divergens) is grown by a nursery in Fulton, north of Santa Rosa, that describes it as follows: “This is a little beauty. Mat-forming and evergreen. Tolerant of wet winters, the shiny round bead-like leaves turn a dark red in full sun. Stays compact and slowly spreads, 2-4 inches tall, reaching about 18 inches in diameter. Blooms starry yellow flowers in summer. Great in rock gardens, planters, useful as an edge plant. Adapts to many soil types. Fully hardy and drought tolerant once established.” Unfortunately, our native Sedums are rarely encountered in the Southern California nursery trade and if anyone knows of a local nursery that grows them, please advise. I did find cascade stonecrop available on eBay for $7.
If you have any stonecrop tales to tell, please send them along to joshua@perfectplants.com. You are also invited to send questions, comments, or gardening practices or problems regarding any plant species and your photos are always welcome, too.