The Ageless Aeonium

Today, we introduce the genus Aeonium, which includes 35 species, most of which are from the Canary Islands, northeast of Africa.

These plants are characterized by the development of rosettes of leaves on basal stems, i.e., stems that rise from the plant’s roots.

The generic name, Aeonium, comes from an ancient Greek word that means “ageless.” In fact, for most species, the rosettes die after producing a flower, although the entire plant lives. A few species are monocarpic, meaning that they produce a single rosette without a stem, and then the entire plant dies.

Popular Cultivars

  1. A. ‘Zwartcop’ (Black Rose), a cultivar of A. arboretum, develops rosettes with very dark reddish-purple, almost black leaves, on stems that can rise to four feet. This plant produces effective displays in the landscape or in a mixed container, especially when contrasted with yellow flowers like those of the plant’s own blossoms.
  2. A. ‘Sunburst’ (Copper Pinwheel), a cultivar of A. davidbramwellii, is a variegated form, with large rosettes with variegated green and white leaves edged in bright, coppery red. The stalks rise up to 18 inches. ‘Sunburst’, like other variegated plants, can provide pleasing contrast in the garden.

Aeonium 'Sunburst' best

  1. 3. A. nobile (Noble Aeonium) produces a single, stemless rosette up to nearly two feet in diameter, making it entirely distinctive among the aeoniums. The leaves are yellowish, with a reddish edge when grown in bright light. This is one of the monocarpic aeoniums: it dies after producing its reddish blossoms.
  2. A. tabuliforme (Saucer Plant, Dinner Plate Plant) is another monocarpic aeonium that provides a single, unique, nearly flat stemless rosette.

Cultivation

Aeoniums will be dormant during the summer months and resume growing in the early autumn.

They are very easy to grow in containers, where they flourish with their shallow roots and occasional watering. Use a normal potting soil, rather than a fast-draining cactus mix. In the Monterey Bay area, they prefer bright morning sun and afternoon shade. Fertilize only when the leaves become yellowish, indicating nitrogen deficiency. Too much fertilizer will promote too-rapid growth and weak stems.

When grown in the garden in this area, aeoniums require little care. As with container plants, avoid very rich soil and fertilizers.

Propagation

All aeonium species and hybrids can be propagated from seeds, but most are propagated easily from stem cuttings. This might be done to produce additional plants or to bring a rangy plant into a more compact form. During the plant’s normal growth period, from autumn to mid-spring, cut a rosette with up to five inches of stem (shorter for smaller, shrub-like forms) and place in a cool shady place for at least three days, to heal over. Then, place the cutting in a normal potting mix, in a small container, and in a shaded, windless location to reduce moisture loss. After the plant has established roots, place in a container or in the garden.

The monocarpic species are not propagated from stem cuttings, but from leaf cuttings, which are more successful with A. tabuliforme than with A. nobilis.

Aeoniums are drought-tolerant plants that are easy to cultivate and interesting additions to the garden.

Updating the Landscape

August might not be the best time of the year to work in your garden.

Even the Monterey Bay area’s temperate climate can be uncomfortably hot for digging (if that is among your priorities).

The early morning hours can be a fine time to keep up the chores, but using that time presumes readiness for an early start and control over the day’s schedule, which is not everyone’s situation.

Still, the lazy days of summer include opportunities for creative advances in the garden.

A priority task that is too often neglected, and could be pursued now in a timely way, is the annual assessment and adjustment of the home landscape.

The assessment process can involve a slow inspection walk through the garden, but ideally includes choosing a vantage point where a comfortable seat and a cool drink will support appraising each significant plant, and envisioning the renewal of the landscape.

Screen Shot 2015-08-15 at 11.01.27 AM

Take a little time for this important task, which can guide progress during cooler days, which are not far off, and chart longer-term improvements.

Right now is also a good time for your review of the landscape because in about two months, with optimism, we will begin our rainy season. At that time, we should have new plants in the ground, because the rains will keep them watered as they become established.

This review presents a good opportunity to recruit a fellow gardener to provide a second opinion. Invite reciprocal visits with someone who both respects the current restraints on your time and resources, and brings a creative perspective to the process.

When appraising the landscape, look for…

  • Plants that have been neglected, and consequently are struggling, dying or already dead.
  • Plants that are overgrown, and have begun intruding on walkways or crowding other plants.
  • Plants that need dividing to perform well. (Dig and replant irises this month and next.)
  • Plants that were misplaced originally, and would look better in another spot.
  • Areas that would be improved by the addition of a new plant of a particular size, blossom color or form.

The last appraisal listed above will require study to identify the right plants for addition to the garden. This could involve visits to the local garden center, or reviews of printed catalogs or websites. A neighborhood stroll is always a practical approach to finding plants that would work well in your garden and flourish your local growing conditions. When you see a desirable plant, ask the homeowner to name the plant so you could search the web for its cultivation needs.

Summarize the findings of the appraisal in a task list with target dates for needed adjustments.

Regular reviews and adjustments of your landscape will keep it looking fresh and interesting. Such reviews could be done annually, as proposed here, or at the beginning of each season.

Our gardens please us because they are alive and always changing, so gardening succeeds best when gardeners interact with Nature.

Water Storage Tricks

With our persistent drought, and the possibility that it signals a long-term change in our climate, gardeners are becoming interested in succulent plants. They warrant a closer look.

All plants store moisture in various parts of their anatomy. Succulent plants store more moisture than plants in general, having adapted to surviving in areas of irregular rainfall.

Succulence is a characteristic of plants, rather than a taxonomic category. As a result, identifying succulent plants can be an arbitrary exercise. For example, some gardeners will group succulents apart from geophytes and cacti, although both store moisture. That’s OK, because “succulent” is not a formal definition, but it’s still appropriate to think of geophytes and cacti as good at storing moisture.

Succulents are found in about sixty plant families, and a wide range of genera within those families.

One unusual group of succulent plant is the caudiciforms, which store moisture in a caudex, which is a woody stem structure that typically develops just under the surface of the soil. Gardeners who enjoy growing these caudiciforms in containers often adjust them to display the caudex above (or partially above) the soil surface. The caudex, also called a “lignotuber,” is not attractive in the conventional sense, but by any name it is an ingenious adaptation of the plant to unreliable moisture conditions.

My garden includes two caudiciform plants. One is a Ponytail Palm (Beaucarnea recurvate), from Mexico, which is not really a palm. The cultivation advice for this plant is to never water. This might seem harsh, especially for gardeners who equate watering regularly with nurturing the plant, but it indicates that the plant is epiphytic, meaning that it derives moisture and nutrients from the air, rain, and sometimes from debris that accumulates around it, and that’s why storage water is so important for this, of course the storage facility that is used is necessary to be in the right condition, if it presents any problems, getting leak sealing services is the best option for this.

Ponytail Palm

Ponytail Palm (Beaucarnea recurvate). Click to enlarge the photo, and make more visible the caudex at the base of the plant.

Screen Shot 2015-08-02 at 8.30.44 PMMy other caudiciform plant is a Beautiful Serpent (Agapetes serpens), which is from the Himalayan mountain range north of India. It is in the Ericaceae (Heath) family. The plant’s specific name refers to the snaky growth of its stems, but its blossoms are more distinctive, in my view.

I have not seen the common name, Beautiful Serpent, online, but that’s what I call this plant.

Screen Shot 2015-08-02 at 8.31.19 PMMy plant is A. ‘Ludgvan Cross’, which is a cross of A. serpens and A. rugosa, both from the Himalayas. This hybrid has distinctive chevron markings on the blossoms.

Both photos of Agapetes serpens are from Strange Wonderful Things: Rare and Exotic Plants which is a fine website for gardeners to visit.

I found this rather rare (or at least uncommon) plant in a local garden center, then found online cultivation advice that emphasized bright but cool conditions, with protection from the afternoon sun. This seemed appropriate for a plant from the Himalayas, so I put in a container of about 1.5-gallon size, filled with good potting soil, placed the pot in a bright shade location, and watered it regularly.

The plant grew well enough, but has produced few stems and blossoms, compared to photos I have seen online. It didn’t seem happy.

With a bit more research, I learned for the first time that this plant is a caudiciform. The caudex is below soil level, so this was a surprise. Then with further research, I learned that it is also epiphytic! This is a game-changer.

Not all caudiciform plants are epiphytic, but they use available moisture very efficiently, so irrigation should at least be limited.

My cultivation plan for this plant now involves keeping it in the same bright shade location, and discontinuing irrigation. Reportedly, it prefers humid conditions, so I might mist it occasionally.

The first takeaway from my experience with this plant is to find more than one source of information on unusual plants that you bring to your garden. The Internet holds an amazing wealth of information of value to gardeners, and we should draw upon it routinely.

An important first step in researching a plant is to learn its botanical name. A search based on a common name often will lead to good information, but the botanical name is more accurate and preferable.

Try one or more caudiciform plants among the succulents in your garden. A rich source of information on these plants is the website bihrmann.com. Hint: when you browse to the home page, click on the image immediately after “.com.”

Incidentally, you might enjoy exploring this website, which has many images of flora and fauna, in several categories. The author, identified only as Bihrmann, has travelled extensively, taken an enormous number of photographs and lived a rich life. Some of the pages are in Danish.

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