Distinctive Broadleaf Evergreens

compact Carolina laurel cherry (Prunus caroliniana 'Compacta')

compact Carolina laurel cherry (Prunus caroliniana ‘Compacta’)

This is the time of year when flowers disappear and deciduous trees are denuded of their foliage.
For serious plant watchers, it’s the time of year when foliage of evergreen trees, shrubs and ground covers takes center stage.
Growing up in Chicago, I thought that evergreen referred exclusively to needled or scaly conifers – to pine, fir, spruce, cedar, cypress and juniper. I had no idea there was such a thing as leafy, broadleaf evergreens, of which Valley gardens predominantly consist. Any broadleaf evergreen – meaning any plant that keeps its leaves year-round other than a conifer – is an anomaly in cold winter areas such as the Midwest.
Whenever I see an olive tree in fall and winter, I appreciate its distinctive aesthetic foliar qualities. Olive trees seem to shine more brightly in cooler weather, under overcast skies, especially after a rain.
Olive is a broadleaf evergreen tree of antiquity. I have seen specimens in Jerusalem that are at least 1,000 years old. Those grizzled trees are never watered, except by winter rain, which is often sparse in the olive’s Levantine or Eastern Mediterranean habitat.
An olive tree may seem somewhat drab up close but, from a distance, it glistens. This effect is achieved by its unique foliage, dark green on its upper side and grayish white underneath. Olive foliage imparts a uniquely fresh and unblemished look, even where a trunk is aged and gnarled.
Depending on the light and the time of day, olive foliage may appear dull green, silvery blue, silvery green or just plain silver. If you are in the market to purchase an olive tree, you will soon recognize that the value of this species is proportional to its age and to the gnarliness of its trunk. Due to the slow rate of olive tree growth, a mature specimen is more costly than that of most other trees.
If you are looking for an ornamental, medium-sized broadleaf evergreen that stays lush throughout the year, ideal both as an accent and as a hedge, you should consider a compact cultivar of Carolina laurel cherry (Prunus caroliniana ‘Compacta’ or ‘Bright ‘n Tight’). A compact Carolina laurel cherry grows to a height of 10 feet and holds its symmetrical shape quite well. It requires a minimal amount of pruning throughout its life. It can grow in full sun or partial shade and does exceptionally well in sunny interior courtyard planters.
There are a number of compact magnolias whose reassuring evergreen presence and large, fragrant white flowers are enhanced by moderate growth and a mature height of around 20 feet.
One popular variety is Magnolia grandiflora ‘Little Gem,’ but there are many others available. Boething Treeland, located just east of the entrance to Hidden Hills, has a selection of compact evergreen magnolia varieties you can examine. Plant the largest specimen you can afford since magnolias can be slow to establish.
Michelia (my-KEE-lee-uh) is a magnolia relative that is deserving of wider recognition and use. It requires partial sun in the Valley and well-drained soil. Once these conditions have been met, it has no rival where gorgeous foliage and aromatic flowers are concerned. Its foliage is reminiscent of an avocado tree’s and its flowers are pungently fragrant. Perhaps there is a tree more beautiful than Michelia, but I have yet to encounter it.
In the Valley, carrotwood is a nearly ubiquitous medium-sized evergreen. It is a dependable, if not terribly glamorous, tree with nondescript flowers and has long been utilized for its toughness, although I have seen it fail where its roots are restricted in narrow planters.
Carrotwood (Cupaniopsis anacardioides), so called because its wood is orange, is not a classic shade tree, but with a mature height of more than 30 feet it will definitely block the sun. It is a reasonably clean tree but may produce nuisance fruit. To minimize fruit production, select a specimen with larger-than-average leaves, water it regularly and prune it on a regular basis. Pruning of any tree stimulates vegetative or foliar growth at the expense of fruit formation.
Evergreen oaks are known as live oaks and a number of species are seen, here and there, in the Valley. Southern live oak (Quercus virginiana) is tolerant of a wide variety of soils and climates. I have seen it used as a street tree on Vesper Avenue opposite Van Nuys Middle School, between Albers and Clark streets.
I have always been an admirer of evergreen pepper trees. California pepper tree (Schinus molle) has delicate, weeping foliage and a distinctive trunk that become contorted and distinguished with age.
It can be appreciated in Hidden Hills, where it is a mainstay of the parkways there. Brazilian pepper tree (Schinus terebinthifolius), an enormously popular selection in the Valley, is more tropical than the California pepper tree and ornamental in a different way, its beauty derived from an umbrellalike canopy of lush, dark-green foliage year-round which, in late fall, is highlighted by large clusters of bright red fruit. Like the olive, pepper trees should not be planted in lawns because of their susceptibility to soil-borne fungi.
Other evergreen trees that bear consideration for their moderate, controllable growth include tanbark oak (Lithocarpus densiflorus), primrose tree (Lagunaria patersonii), and Catalina ironwood (Lyonothamnus floribundus). Lemon bottlebrush (Callistemon citrinus) is actually a large shrub that is frequently trained as a tree. Its scarlet flowers are abundantly displayed as it reaches a mature height of 25 feet.
Two warnings
Nick Kurek of Granada Hills emailed a warning regarding croton, discussed in last week’s column. Croton (Codiaeum) is toxic and should not be accessible to pets or children.
Kitty Venne of Santa Clarita emailed a warning concerning cocoa shell mulch. This mulch is attractive to dogs which, should they consume it, may become violently ill or die.
Tip of the week
Melaleuca trees, from Australia, are not only evergreen but have a variety of ornamental qualities and considerable drought tolerance as well. Many have furrowed, peeling or spongy bark including, most notably, paperbark tree (Melaleuca quinquenervia). Lilac melaleuca (Melaleuca decussata) has caterpillar flowers as does the red granite bottlebrush (Mellaleuca elliptica). Pink melaleuca, or showy honey-myrtle (Melaleuca nesophila), has lavender pink pompon flowers. All of these trees may develop iron deficiency-induced chlorosis or yellowish leaves in our alkaline soil, so add lots of compost when planting and keep a layer of mulch on the soil surface at all times. If yellowing should still occur, fertilize with any product recommended for acid-loving plants.

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