Living Sculpture

When talking about a garden recently, my friend David commented that it needed more sculpture. To be precise, he said it needed more Sculpture. I was imagining a feature like Rodin’s Thinker, but what he meant was that it needed more living sculpture, or plants with a particularly dramatic (dare I say Architectural?) presence. Since we are both from California, we bemoaned the fact that we couldn’t plant our favorite sculptural plants here in New Mexico. It is too hot in the summer, too cold in the winter for tall palms, Phormiums, Astelia, Strelitzia, Cereus, Aloe, Dicksonia, Cordyline, Ensete, Gunnera…the list went on and on. Given that these plants cannot be grown here, what options do we have? The first is accepting that the character of the high desert is not that of subtropical areas. Here we live in an area of brushy, mounding grays and browns. Frankly, that is the character of this region and even why we love it. Why not embrace it? A second option is seeing what plants we do have, that have the sculptural character that we crave, but are more appropriate for this region.

I asked David what he meant by “Sculpture,’ and he began with the genus Agave. There is not doubt that Agave are sculptural, and although many are subtropical, there are also many that are hardy here. Agave parryi is the best known in Albuquerque, and for good reason. It is easy to grow, easy to find and plants are of good size and form. They slowly grow to form 3 foot high and wide (or more) gray-green rosettes. After a good 12-20 years, a flower stem like a mammoth asparagus stalk forms. It grows what seems two feet a day until 25 feet tall, branches and produces clumps of yellow brush-like flowers loved by both birds and bees. The plant then dies (but pups live on, so don’t dig them all out in the meantime). Now that’s fireworks.

You might think that the hardy agave are variations on a theme after seeing Agave havardiana (slightly bigger), but don’t be so quick. Agave scabra has similar leaves, and looks similar as a tiny plant, but leaves aren’t as broad and grow longer. Frequently they have a graceful curve to them that produces a plant that has the appearance of a many-petaled lily tulip. This one won’t wilt after a week. Agave lechuguilla isn’t called shin-digger for nothing. It is the right height (12 inches or so) that if you are tromping around them without protection, it’ll give you a reminder you won’t forget. The plants have few leaves that are yellow-green swords held staunchly upright. They may be dangerous to the unaware, but the staunchly upright swords in clusters are impressive. Agave parrasana is a wickedly spined (and strikingly beautiful) artichoke. In case you need further clarification, Yucca-Do Nursery has one called ‘Meat Hook.’ I started looking for a place to put one the moment I set eyes on it. For a completely different look, set your sights on Agave striata and the closely related Agave stricta. Looking like sea anemones, these are said to have “pencil-like” leaves, but I would be more likely to compare them to skewers.
Yucca can be similar to agave in form, and are in fact more woody lilies. But most Yucca don’t die after bloom (Y. whipplii does), they produce a white or nearly white flower, and many species form trunks that put that plant at tree height. There’s probably no need to introduce these, since the Soaptree Yucca (Yucca elata) is the state flower of New Mexico. The flowers are incredible towers of white flowers, but since these last only a couple of weeks, count on the sculpture of the plants instead. There’s also the huge Yucca faxoniana, which you see around UNM. A friend in Socorro has one that is at least 25 feet tall with a fifteen foot leaf-spread. Look also to Yucca rostrata, the Beaked Yucca, or yucca rigida (the Blue Yucca) for tree sized sculpture in fine leaves or steely blue. The yucca that don’t form tall trunks can be sculptural also. Consider Yucca baccata, the Banana yucca at an easy 5 foot diameter of thick green leaves and short trunks when very old. Or the relatively diminutive Yucca harrimaniae. All these yuccas are dramatic when lit at night. Don’t bother with the frequently seen Yucca recurvifolia or Yucca filamentosa if you are looking for sculpture. Although safer to be around, those soft leaves droop and flop, losing the drama.

More spiny plants for sculpture (this is the desert after all), include Opuntia. Lest you groan with boredom at the thought of common Opuntia phaeacantha, look also to Opuntia engelmanii with its dramatic foot-plus pads and four-by-five foot plants. As are many opuntia, this is very dramatic when night-lit. Remember also that common is not equivalent to bad. Take for example Cylindropuntia imbricata (Tree Cholla). What could be more sculptural? What could be more indicative of the high desert? For a different kind of spiny sculpture, ocotillo is thought of as a low desert plant, but I’ve seen many fine specimens around town. The red flowers on spindly stems are a give-away.

Just because I’ve mentioned all spiny plants so far, not all sculptural plants need to be health hazards. The bare branches of some trees with a backdrop of winter sky is as dramatic as anyone can ask for. The sparse branches of Rhus glabra come to mind, and this small tree has the added advantage of brilliant fall color, which is uncommon in the desert, and great drought tolerance. Be aware of the tendency to sucker, however, a fact that I ignored until it abruptly came to my attention.
Two trees that seem to come directly out of Tim Burton’s movies are Crataegus crus-galli and Celtis reticulata. You’d never guess how dramatic they become if all you saw was the cute young saplings in gallon cans, or the pictures in books. The mature Celtis reticulata in my neighbor’s yard has your basic “tree shape” in the summer, but come winter, the sinuous branches lined with short branchlets come to the fore. I stopped my car in the middle of the road the first time I saw it. If you get a chance, look at the Crataegus crus-galli in the Denver botanic garden. Black trunks and stems that are low branching at odd angles and long 4 inch spines (sorry, but I had to mention another “health hazard” plant) make an imposing picture. The Nightmare Before Christmas indeed.

The much-maligned juniper makes an artistic silhouette. In addition to the famous Hollywood Juniper (Juniperus chinensis ‘Torulosa’), there is exclamation point of Juniperus scopulorum ‘Skyrocket’ or my favorite kid-in-a-ghost-costume Juniperus scopulorum ‘Moonglow.”

Grasses can make for striking structure in the garden as well. Choose the 10-foot tall Erianthus ravennae for its starkly upright culms over the formless Pampas Grass (Cortaderia selloana) any day. Vertical is the rule with Panicum virgatum ‘Heavy Metal’ and Calamogrostis x acutifolia ‘Karl Foerster.’ Both form a nice contrast to the mounded forms of many native plants such as Eriogonum jamesii. Planted together, ‘Heavy Metal’ has more upright leaves than Karl, and are glaucous blue-green compared to Karl’s mid-green fountains. Karl also grows and blooms rapidly in the spring, with fluffy green-purple flowers that fade to the slim beige spikes that we know so well. Heavy Metal takes the summer to put on growth, the diaphanous red seed panicles forming in the fall. Both take a bit of water in this climate.

Other non-native plants that produce dramatic sculpture in the garden are contorted forms of plants. This could include the twisted black locust (Robinia pseudoacacia ‘Tortuosa’), Hollywood juniper (Juniprus chinensis ‘Kaizuka’) or contorted flowering quince (Chaenomeles speciosa ‘Contorta’). I’m curious to try the contorted form of bitter orange (Poncirus trifoliata ‘Flying Dragon’).
So who wants to be in California anyway? Here we have the beauty of the high desert, with its mesmerizing rhythms of rounded forms and muted color palette. But if you want something with the dramatic impact of a Rodin sculpture, you have options here. Ever see a Yucca elata look as good in California? With sculptural plants such as these, we can keep our sense of place, and we can have the sculpture too.