Angel’s Trumpet

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Powerful fragrance combines with docile color.

Human intervention has sustained the seven species of angel’s trumpet, Brugmansia, since their prehistoric extinction from the wild. They were likely endemic to tropical regions from Venezuela to Chile, and southeastern Brazil. Their extinction was likely a consequence of the natural extinction of animals that dispersed their seed. Most garden varieties are hybrids of the various species.

Angel’s trumpet is either a big shrub or small tree, with rather herbaceous stems. The more popular cultivars can get more than eight feet tall. Cultivars that might get twice as tall are rare. The soft leaves get about six inches long and half as wide. Leaves might get almost twice as long on vigorous growth. Some cultivars have slightly tomentous (fuzzy) foliage. A few have variegated foliage.

Although generally sporadic, and pastel hues of pink, orange, yellow or white, bloom is impressive. The pendulous trumpet shaped flowers are commonly longer than six inches, and half as wide. Double flowers are frilly. Several cultivars are delightfully fragrant, particularly in the evening. All plant parts are very toxic. Plants damaged by frost in winter are likely to regenerate from their roots.

Fragrant Flowers Have Ulterior Motives

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Demure daphne bloom is richly fragrant.

Many who enjoy gardening appreciate fragrant flowers. Many grow particular flowers specifically for their fragrance. Yet, not many consider why so many flowers are fragrant. Plants can not enjoy their own alluring floral fragrances any more than they can enjoy their own delightful floral colors and forms. They do not expect people to enjoy their bloom either. Human appreciation is incidental.

Floral fragrance is merely intended to attract pollinators. Flowers are inanimate, so rely on either wind or animate pollinators to exchange their pollen among other flowers. Animate pollinators are mostly insects, but may be birds, bats or other animals. Flowers do what they must to attract their preferred pollinators. Many use color and floral form. Many use fragrance. Some use both tactics.

Flowers that use both color and fragrance to attract pollinators are mostly endemic to densely forested ecosystems. There is more competition for pollinators within such ecosystems than there is within ecosystems of sparser vegetation. Otherwise, fragrant flowers are generally not as colorful as those that are not as fragrant. Likewise, the most colorful flowers are generally not so fragrant.

Angel’s trumpet is striking in bloom because the flowers are so large. Wisteria and lilac that bloomed last spring were spectacular because they were so profuse. The pastel hues of their blooms are no problem that their fragrance does not compensate for. Pink jasmine and mock orange are about as fragrant, even if their color range is more limited. Star jasmine is not always so profuse.

Pittosporum tobira and Pittosporum undulatum are even less visually impressive in bloom, but can be surprisingly fragrant. The tiny but richly fragrant flowers of sweet osmanthus, sweet box and night blooming jasmine are so obscure that other bloom is often credited with their fragrance. As the name implies, night blooming jasmine is powerfully fragrant after sunset during warm weather.

Freesia, hyacinth, narcissus, lily and some bearded iris are both colorful and very fragrant.

Dragon Lily

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Dragon lily is striking and stinky.

Dracunculus vulgaris make a sinister impression by botanical name alone. Common names include dragon lily, dragon arum, dragonwort, black dragon, snake lily, stink lily and voodoo lily. That makes it sinister enough to be compelling. Although rare in nurseries, dormant tubers are available in season by mail order. Alternatively, established colonies happily share a few dormant tubers.

Dragon lily is quite easy to grow. It appreciates rich soil and regular watering, at least until it gets established. Once settled in, it might be satisfied with only monthly watering until it goes dormant in late summer. Because it prefers humid climates, it wants shelter from wind here, and may like a bit of partial afternoon shade. It is so adaptable that it unfortunately naturalized in some regions.

The fragrance of dragon lily attracts insect pollinators that are drawn to dead animals. Those of us who enjoy unusual plants find it amusing. Everyone else thinks it stinks. Blooms that produce the fragrance are spectacular, with a big and flared purplish red spathe around a slender black spadix. They may stand nearly three feet tall, among lightly blotched and deeply lobed palmate leaves.

Stinky Flowers Serve Their Purpose

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Some beetles like stinky flowers too.

From a human perspective, flowers should not be stinky. They should be pretty and colorful, and perhaps delightfully fragrant. Many flowers in landscapes and home gardens actually are. After all, they are grown for their appealing bloom. Many plants that provide only foliage produce wind pollinated flowers. They are not particularly pretty, colorful or delightfully fragrant, but not stinky either.

Flowers do what they must to pollinate each other. Since they are inanimate, they rely on pollinators or wind to disperse their pollen. Those that rely exclusively on wind produce an abundance of very fine pollen, but waste no effort on attracting pollinators. All other flowers use customized combinations of colors, patterns, textures, fragrances and flavors to attract their preferred pollinators.

There are all sorts of pollinators. Bees are the most famous. There are many other insects too. Hummingbirds and butterflies are very popular. Bats do their work at night while no one is watching. Of all the pollinators though, flies are likely the least popular. Many of the flowers that produce fragrance to attract them are not exactly popular either. Alas, fly pollinated flowers are stinky flowers.

Stinky flowers are naturally uncommon. Apparently, not many flowers want to rely on flies. Stinky flowers are even more uncommon in home gardens and landscapes, for the obvious reason. Paw paw and carob production relies on stinky flowers. A few of the various arums grown for dramatic bloom are stinky too. Philodendron bloom is quite stinky, but very rare among foliar houseplants.

Pear and hawthorn do not rely on flies, so are only incidentally and mildly stinky.

Fortunately, stinky flowers are not often a problem. Paw paw trees are rare here. Carob trees bloom somewhat briefly. If philodendrons bloom at all, they produce only a few flowers which can get pruned off. Regardless, fragrances of stinky flowers are generally not as strong as appealing floral fragrances. They neither disperse as efficiently, nor linger as long. Some are too faint to offend.

Horridculture – Stinky Flowers

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Rhody was not impressed, and he is an expert on fragrance.

Dracunculus vulgaris – dragon lily. It was featured in the gardening column for next week, both as an illustration for the main topic, and as the ‘highlight’ species. It is as unappealing as the name and the pictures suggest, but it sure is interesting. It has several more equally unappealing common names. We know it as ‘death arum’ because that is the first name we came up with.

Besides, it smells like death. Yes, it stinks. It does so to attract flies for pollination. Actually, it attracts quite a few annoying insects. I can not explain why, but insects who congregate around stinky flowers are as unappealing as the fragrance that draws them. They are certainly very different from the appealing bees and butterflies who pollinate flowers with appealing fragrance.

The first of these death arums mysteriously appeared in the garden of a colleague several years ago, and promptly multiplied by both seed and disbursement of tubers. There are now a few expansive colonies that continue to expand. Cutting down the foliage does not slow them down much. The fragrance, which is not too bad individually, is getting to be bothersome collectively.

My colleague brought me one of the tubers to confirm the identity. I got a picture of it since it was here, but then did not know what to do with it. I did not want to toss it aside into the forest like I do with so much other greenwaste. It could have grown into a problem. I did not want to discard it either, since it was viable and healthy. So, I canned it and put it aside in the nursery.

This is the result. It is not as stinky as I expected it to be. I still do not know what to do with it.

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These unidentified beetles that I had never noticed here before arrived promptly for the stinky bloom.

 

 

 

Sweet Box

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Foliage of sweet box outdoes flowers.

While bloom cycles of most plants are accelerated by the unusually warm winter, sweet box, Sarcococca ruscifolia, seems to be blooming a bit late. It should have bloomed sometime in winter, and finished a month ago. The tiny pale greenish white flowers are certainly nothing to look at, but they produce a remarkably rich fragrance that seems like it would be delicious with coffee.

The foliage is very glossy and dark green, like that of English holly, but the leaves are small and lack spines. Red berries sometimes develop, but are only abundant enough to be notably colorful on plants that are distressed. Sweet box may take a few years to get established and grow to only about three feet high and wide, although it can slowly get a bit larger.

Since it is naturally an understory plant, sweet box prefers at least a bit of shade. Harsh exposure fades foliage. Because of its tolerance of partial shade, as well as its low and dense growth, sweet box is ideal for obscuring foundations. After the first few years, it does not need too much water. It gets established more efficiently in rich soil.

Good Looks Are Not Everything

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Less color can mean more fragrance.

More flowers bloom as winter becomes early spring than at any other time of year. For many flowers, bloom is significantly accelerated this year because winter was so very warm. Flowering cherry, purple leaf plum and most of the stone fruit trees (such as almond, cherry, apricot, nectarine, peach, plum, prune and all their various hybrids) have already bloomed.

Color is what gets noticed first. After all, that is what all the flashy colors are intended for, to get the attention of pollinators. Yet, there is more to the indirect mating strategies of flowers than color. Because flowers lack the mobility to pollinate each other, they do what they must to attract others to disperse their pollen for them. Some use fragrance.

Generally, flowers prefer one tactic or the other. This is why the most colorful flowers lack fragrance, and the most fragrant lack color. Gardenia (which is not easy to grow locally), star jasmine, honeysuckle, Pittosporum tobira, Pittosporum undulatum and night blooming jasmine are not exactly colorful while blooming. The powerfully fragrant flowers of sweet osmanthus and sweet box barely get noticed.

Pink jasmine and mock orange (Philadelphus spp.) are flashier, only because their blooms are so profuse. Southern magnolia has spectacularly big flowers, but they are mostly obscured by dense foliage high above view. Cereus cactus and moon flower are likewise spectacular, but bloom at night to attract nocturnal moths for pollination.

Only a few flowers are both colorful and fragrant. Lilac and wisteria are among the more familiar. Both bloom early in spring, with a similar color range of lavender, blue, pink and white. Lilac is shrubby. Wisteria is an aggressive vine. ‘Charles Grimaldi’ angel’s trumpet is a big shrubby perennial that blooms rich yellow, but may only be fragrant at sundown.

Freesia, hyacinth, lily and bearded iris are flashy and fragrant flowers grown from bulbs, although hyacinth and most lilies rarely bloom a second year, and many lilies and bearded iris lack fragrance. Sweet alyssum is a mildly fragrant annual that blooms white, pink or lavender.

Winter Daphne

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Simple daphne flowers produce complex fragrance.

While winter weather is still cool and damp, winter daphne, Daphne odora, provides an alluringly fresh fragrance of spring. It is easy to dismiss the abundant but rather small domed trusses of tiny pastel pink flowers as the source of their formidable fragrance. Like so many fragrant blooms, daphne bloom is visually demure. Nevertheless, blooming stems are delightful with other cut flowers.

‘Aureomarginata’ is the most popular cultivar of daphne, and is the only cultivar available in many regions. The handsomely glossy evergreen foliage is variegated with yellowy white or light yellow margins. Mature plants get about two feet tall and about twice as wide, with a delightfully tame hemispherical form. They may get slightly taller with slightly less refined form where partially shaded.

Daphne prefers rich and loose soil, and with sufficient organic matter, will tolerate rather sandy soil. Partial shade might inhibit bloom somewhat, but is otherwise not a problem. Proper placement is important. Established daphne recover slowly from transplant. It is also important to be aware that even the healthiest of plants may live for only five years, and rarely live for more than ten years.

Gardenia

40917It seems that everyone who has ever experienced the seductive yet powerful fragrance of gardenia, Gardenia jasminoides, wants to grow it, but very few actually can. Gardenias like warmth, but prefer more humidity than they get here, which is why they seem to be happier in partial shade, in atriums, or in urns that can be moved out of harsh exposure during summer. In such sheltered spots, aphid, scale and sometimes whitefly can be problematic.

Gardenias want their own space, where their roots will not be bothered by excavation or roots of more aggressive plants. They do not even want annuals around them, because annuals need such regular cultivation. Docile ground cover plants or simple mulch is best. Gardenias like rich soil and acid fertilizer or fish emulsion to be applied regularly as long as the weather is warm.

The creamy white flowers that fade to French vanilla can seem mundane relative to their alluring fragrance and handsomely glossy foliage. The largest flowers rarely get to three inches wide. ‘Mystery’, which can slowly get four feet tall, is the most familiar cultivar, even though it does not bloom so much after spring. ‘Veitchii’, which can eventually get three feet tall and twice as wide, has small inch-wide flowers, but is still blooming. Modern cultivars bloom just as late, but with larger flowers.

Star Jasmine

90619There is some debate about the origin of the common name of Confederate jasmine. Some attribute it to its popularity in the former Confederate States of America. Others believe it originated in the Malay Confederacy, much closer to its native range. That is irrelevant here, where we know this popular vine with very fragrant flowers simply as star jasmine, Trachelospermum jasminoides.

One might think that it is too common, but there are reasons for that. The dark green foliage is so delightfully glossy all year. As appealing as it is alone, it is even better as a contrasting backdrop for the small but strikingly white star shaped flowers that bloom in profusion about now, and continue to bloom sporadically for much of the rest of the year. The lavish fragrance is totally awesome!

The twining vines climb luxuriantly to about the height of first floor eaves. They can climb much higher, but higher growth takes a while to get as billowy as lower growth. However, it is more often grown as a shrubby ground cover, only about two feet deep. The simple leaves are two to three inches long, and one to one and a half inches wide. The clustered flowers are about an inch wide.