Joshua Siskin writes the garden column each week.
Fall is the best time to plant and flowering woody perennials.
Those that bloom in the fall are among the most desirable garden selections and warrant special attention in this season. Being woody, they generally survive without much water, even if they originate in areas whose annual rainfall exceeds our own. In any event, here is a list of some of my favorite woody perennials that flower around this time:
1. The cigar or firecracker plant (Cuphea ignea) is a robust, highly floriferous woody perennial. Its one-inch-long tubular flowers are orange, tipped in yellow; hence its common name. It may bloom at any time of the year but it really lights up in the fall. Its mass of cylindrical orange flowers with yellow tips glow brightly under autumn’s darkening skies. The leaves are diamond-shaped and glossy green. It grows slowly to a height and girth of three to four feet and only needs pruning to keep it in bounds on an occasional basis. It flowers so heavily that shoots have been known to bend over and flop under the weight of their blooms. Hummingbirds flock to it. While resistant to drought once established, it will flower more heavily when soaked once every other week in hot weather. Propagation is by shoot tip cuttings which is easily accomplished in fall or spring. Cigar plant grows well in both full or partial sun.
2. Orange cestrum (Cestrum aurantiacum) is a bold pillar of a plant that can reach up to ten feet tall and is covered with tangerine-colored blooms at summer’s end. Red cestrum (Cestrum elegans) has wine-red flowers that can bloom at almost any time but are especially noticeable under gray November skies. Red cestrum inflorescences, each of which consists of more than 20 upward-facing tubes, explode on shoot terminals like a Fourth of July fireworks extravaganza. Lastly, there is night jessamine (Cestrum nocturnum) whose myriad flowers have no color but make up for this deficiency with an intoxicating perfume that migrates at night.
3. There are many plants known as butterfly bush. Some have this name because they attract butterflies and others have flowers that look like butterflies themselves. Cassia bicapsularis is a butterfly bush in the latter category as its pale yellow flowers suggest lepidopteran creatures. There is some controversy regarding whether this is a shrub or a tree since it may grow from 5 to 25 feet tall, depending on the circumstances. Mine was around two feet tall when I brought it home from the nursery exactly three years ago and today it is six feet tall. This is a treasure of a plant due to its plethora of blooms yet sparse growth habit so that you need not do anything as far its care is concerned other than watch it grow.
4. Russian sage (Perovskia atripliciolia) is a tough, versatile shrub that is covered with lavender-blue flowers from summer into fall. It grows rampantly to five feet but may be cut back radically – since its thick accumulation of interior stems may die and need to be cleaned out – before new growth starts again in the spring. Like many of the plants in this list, it makes a stunning hedge during its period of heavy bloom.
5. Glossy abelia (Abelia x grandiflora) is an unsung hero of the partial sun-to-light shade garden. It flowers at virtually any time of the year with small tubular white flowers. Its shiny leaves are always a welcome sight, resembling those on the aforementioned cigar plant. Resist the temptation to prune its wayward stems which arch romantically into the air to a height of six feet or more. There are smaller Abelia cultivars with pink flowers or variegated foliage but they are weak performers that cannot compete with the durability or flower power of the classic Abelia.
6. Heliotrope (Heliotropium arborescens) is one of the most fragrant woody perennials. Its flowers have an aroma that combines hints of licorice, anise, marzipan, and vanilla. Flowers are purple and born in clusters above dark green foliage. It is native to Peru and generally recommended for sunny exposures but in Southern California, except along the coast, it must be protected from afternoon sun. Height of mature plants is around four feet.
7. Dwarf plumbago (Ceratostigma plumbaginoides) is a stunning selection for the fall garden. At this time of the year, its true blue flowers — true blue is extremely rare among flowers — are on display, offset by foliage that takes on a reddish cast. This could in all fairness be classified as a ground cover, yet its distinctive look is so arresting that it easily earns the status of a stand alone selection, especially in a container. It only grows about one foot tall but spreads for many feet. When it starts to look piqued, you can remove the declining portions of the plant; where its stems touch the ground, they will have rooted and so you can leave these rooted portions in place or transplant them to other parts of the garden.
California native of the week: Elymus condensatus ‘Canyon Prince’ is a variety of native California wild rye that lends itself to parkway planting. It is highly attractive underplanted to the two classic California native shrubs: manzanita (Arctostaphylos species) and California lilac (Ceanothus species), with its contrasting blue foliage. It also produces attractive two-foot blue flower stalks that stand up well in vase arrangements. It prevents erosion when planted on slopes and is drought tolerant although it can tolerate irrigation. You will want to cut it back every now and then to keep it compact and aesthetically pleasing.
If you have a flowering woody perennial to recommend, please let me know about it by writing to joshua@perfectplants.com. Readers are encouraged to send me questions and comments about any plant or gardening practice. Suggestions for plant care and solutions to garden problems are always welcome, as are your photos, with horizontal orientation, for possible publication.
