Q. We are looking for a tree to replace our large magnolia that provides good shade – in addition to fallen leaves that last an eternity. We’d like a tree that will grow fairly quickly and that will top out at 15 to 25 feet, with a spread of 15 feet, or so. We also need a tree that does not require a lot of maintenance. – Steve Higbee, Banning
You may wish to replace your existing magnolia — whose “fallen leaves that last an eternity” reveal its identity as a southern magnolia (Magnolia grandiflora) — with a saucer magnolia (Magnolia x soulangeana).
No matter your mood, your soul will brighten at the sight of a saucer magnolia in full bloom; its flowers are fresher, cleaner, and more refined than those of any other tree. The deciduous saucer magnolia’s floral display is enhanced by the fact that flowering takes place when the tree is still leafless as winter ends. In this state, you see what looks like, at the moment of anthesis (when flowers open), hundreds of brilliantly burning lamps on an arboreal candelabrum.
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These barely opened blooms have also been compared to tulips, goblets, and water lilies. A few days later, all petals lay down flat and the flowers do briefly take on the look of saucers. Actually, it is only the outside of magnolia petals that have color, while the inside of the petals is white so that when they drop to the ground and distribute themselves evenly around the base of the tree, they could be mistaken for a thin layer of freshly fallen snow.
Saucer magnolia has other features that set it apart from most trees. Its leaves are large, flat, oblong and lime green in color. Unlike the leathery leaves of the southern magnolia that defy decomposition, these leaves are thin and make an excellent mulch. Its fat, fuzzy flower buds, likened to certain insect antennae, have unique charm. Bark is a tawny gray and, at maturity, this tree’s branching structure is a highly symmetrical dome that requires little if any pruning. If you should have to cut a wandering shoot or stem, prune it all the way back to the trunk; a stem cut in the middle may have trouble healing from its surgery and provide entry to disease organisms. With a height and spread of 25 feet, saucer magnolia is ideal for small spaces and, for strictly ornamental purposes, may be grown up a trellis on the facade of a house or other structure.
Of course, the most outstanding ornamental assets of this tree are the aforementioned flowers which appear in every version of pink and purple with milky white varieties available as well. An added bonus of the saucer magnolia is its cold tolerance. It flowers just as brilliantly in New York City as it does in Los Angeles. The problem growing it in low-humidity areas such as our own is that its foliage begins to crisp around the edges as weather warms and may be completely burnt when summer ends.
Saucer magnolia is a hybrid, indicated by the “x” between its genus and species names. Although both parents are from China, their seeds were brought to Europe and hybridized in France. In fact, the genus Magnolia is named for the French botanist Pierre de Magnol, while the Soulangiana species name is meant to honor Etienne Soulange, the Parisian hybridizer of this species.
Another small to medium-sized tree to consider is the gold medallion tree (Cassia leptophylla). The mature height and spread of a mature gold medallion tree is around 25 feet. In the shade below, you can place a picnic table for having lunch al fresco on a summer day. Gold medallion flowers are a brilliant yellow and open in large clusters in June and July. Faded flowers are followed by long chocolate brown pods, which impart considerable ornamental interest of their own. These pods may grow up to two feet in length. Kids enjoy shaking them like castanets since the seeds inside make noise as they rattle around. Attractive dark, fissured bark is showcased when leaves drop off, if only briefly, during the winter. Although native to Brazil and considered a tropical species, gold medallion trees can survive temperatures in the mid-20s and are highly drought tolerant, too.
The ideal small shade tree is a Japanese maple (Acer palmatum). The species — as opposed to most named varieties that never exceed 10-15 feet in height —eventually grows up to 20 feet tall or more with an equal spread but you will need to wait a while for it to reach this size. A Japanese maple of these dimensions is currently on display at the Huntington Gardens in San Marino and I also saw one growing in the Reseda garden of horticulturist Loren Zeldin. Its leaves invariably turn crispy in summer which deters some people from growing it but while those leaves are on the tree they provide sufficient aesthetic virtue to justify the Japanese maple’s garden presence. Protect it from strong winds and grow it shielded from the hottest summer sun or on the east or north side of your house.
The chaste tree (Vitex Agnus-castus) is a fast-growing species that, at maturity, reaches dimensions of 25 feet in height and girth. Flowers are bluish-violet and crushed leaves emit a pleasant fragrance. California redbud (Cercis occidentalis) grows to 20 feet tall and wide. However, you will need to remove suckers so that it channels its growth into a single trunk whose branches will eventually provide shade. Where fruit trees are concerned, both the loquat and the persimmon will grow 20-25 feet tall with equal spread.
A final tree that provides shade while staying of moderate size is the silk tree or mimosa (Albizia julibrissin), with a habitat that stretches from Japan to Iran. It rapidly reaches a mature height of 25 feet with a wider spread and has a distinctive umbrella canopy. Its flowers are highly decorative, feathery pink and white, resembling badminton shuttleco*cks with an alluring fragrance. The problem is the litter that flowers and seed pods that follow them create. The silk tree is not long-lived with a lifespan of two or three decades. Still, due to its tolerance of summer heat and rapid growth, it remains highly popular in our part of the world.
California native of the week: There are several California sunflowers that you might want to plant when it comes to pollinator plants, as they are especially attractive to California native pollinating bees. Interestingly enough, the classic sunflower species (Helianthus annuus) that we associate with Kansas — since it has the status of state flower there — is also native to California. No, you will not see the more familiar giant sunflowers, which are intensely hybridized, growing wild here or, for that matter, in Kansas, but this annual species, often growing in a clump, is native to 48 states. It is also the only North American native plant that has worldwide commercial importance. You can find annual California sunflower seeds at the Theodore Payne Foundation Nursery (theodorepayne.org) in Sun Valley. Depending on the strain, flowers may only be several inches across but they are abundant while plant height is highly variable.
Do you have a recommendation for a tree that is around 25 feet tall and wide at maturity? If so, please send it to joshua@perfectplants.com. Your questions and comments, of course, as well as gardening problems or gardening tips, are always welcome.
