Gardening : Heavily Scented Flowers, if Fragrance Is Your Forte
Most of us gardeners want more than just pretty flowers. We plan our landscaping and gardens with good scents as well as pleasing color, but some of those fragrances turn out to be more powerful than we bargained for.
Perhaps you have noticed a cloyingly sweet smell that steals through your open windows (and even through closed ones) on summer evenings lately. Undoubtedly, this powerful perfume is exuded by the blossoms of night-blooming Jessamine (Cestrum nocturnum), which releases its heady fragrance from tubular greenish-yellow flowers only after night falls.
This shrub was tops on my list of fragrant plants when we landscaped years ago, but I’m having second thoughts about it. It grows vigorously and its white, pea-sized berries delight birds in the garden. However, its knockout aroma is almost too potent for sensitive noses.
Pruning Advice
If you enjoy powerful perfume, plant Cestrum in a semi-shaded spot where it will have 5 to 10 feet to spread out. Expect it to reach 10 feet or more. During the growing season, prune selectively but not too heavily if you want ample fragrant flowers in July and August. After bloom ceases or after the berries drop, cut it back severely. In my garden, Cestrum grows so outrageously that I nearly have to lasso it to keep it home on the range.
A garden that features fragrance will naturally include some of the heavy scents and, after all, as the prolific and opinionated garden writer Beverly Nichols remarked: “To be overpowered by the fragrance of flowers is a delectable form of defeat.”
Another powerfully scented but delectable nose-grabber is “Star Jasmine” ( Trachelosperum jasminoides ). Like night-blooming Jessamine, it is not a true jasmine; however, its rich floral scent apparently suggested jasmine to admirers.
In addition to offering fragrance, “Star Jasmine” is attractive and amazingly versatile. Nurseries and garden centers stock “Star Jasmine” vines trained to grow on trellises, as ground covers, in hanging pots, as woody shrubs and into pillars. All it takes is judicious pruning.
This tractable treasure looks fine as a ground cover under trees but is especially successful cascading from raised planting beds. Although “Star Jasmine” tolerates full sun, its leaves may become scorched. Better to locate it in partial shade. The small white flowers are exceedingly fragrant in May and June, and a massed bed in full bloom is indeed a noseful.
Another powerful jasmine-like fragrance emanates from Gardenia jasminoides. My garden always will include a gardenia whether I like its fragrance (which I do) or not, because my first corsage was a gardenia, and both the flower and the fragrance have sentimental value. Gardenias also appeal to me because in colder parts of the world these coveted flowers are restricted to hothouses. As a transplanted Midwesterner, even after 25 years I continue to marvel at the horticultural gifts our moderate climate bestows.
Much as I admire gardenias, however, I regard them as I do cats: They are finicky and sometimes indifferent ingrates. My pampered “Veitchii” gardenia produces just enough blooms to prevent its replacement, but it never looks happy.
A non-gardening friend in Pacific Palisades, on the other hand, grows magnificent florist-quality gardenias on a 10-year-old plant that dazzles visitors. Her gardenia (probably “August Beauty” or “Mystery”) is in a raised planter on the northwest side of the house where it receives three hours of afternoon sunlight in the summer and none in the winter. She feeds it once a month during the growing season with an acid fertilizer and never lets it dry out. When the house was sandblasted a few years ago, the gardenia was cut back radically, but it rebounded and continues to bloom shamelessly.
Clearly, the keys to gardenia culture are good drainage, constant moisture, acid fertilizer and limited sunshine. The soil should be amended with plenty of redwood compost. Avoid peat moss, an old favorite, because this soil amendment is nearly impossible to moisten once it dries out. When planting, place the top of the gardenia root ball a little above the soil surface to improve drainage.
If gardenia leaves turn yellow, this may be, oddly enough, a sign of either overwatering or underwatering, because both conditions produce similar symptoms. To determine whether a plant is getting too much water or too little, use a moisture meter before and after watering. Or dig a small hole to inspect the root mass. Is the soil soggy or rather dry? My own gardenia probably is suffering from poor drainage, so in the fall I plan to move it to a raised planter bed.
All the powerful scent-makers described here are permanent shrubs that can be planted now or later in the month when the weather cools a bit.
