The Handbook on Oleanders

9

And since to took at things in bloom

 Fifty swings are little room,

 About the woodlands I wilt go

To see the cherry hung with snow.

A.E.Housman

A Shropshire Lad

Oleanders in the Landscape

In a letter to Clarence Pleasants in Norfolk, Virginia, in July of 1964, Donald J. u nre Superintendent of the Botanical Gardens in Bermuda wrote: "Bermuda is indeed famous for its oleanders. The plant is so prolific and well established that visitors may be forgiven for considering it a native, when in actual fact, it is an introduced subject.... Nathaniel Lord Britton, Ph.D, Sc.D., LL.D., one time Director-In-Chief of the New York Botanical Gardens, had this to say in his 'Flora of Bermuda, published in 1918 by Charles Scribner's Sons, New York: 'In nearly all situations except saline ones. Naturalized. Native of the Orient. Recorded as introduced to Bermuda in 1790, now one of its most beautiful floral features, blooming more or less throughout the year, most freely in Spring and Summer."' Mr. Moore went on to mention that plants grow rapidly in Bermuda, are evergreen and found in single, semi-double and double forms in a wide range of colors, the most common being a : "re pink and a pure white though the colour range extends through cream to deep red. Landscape uses of oleanders in Bermuda include hedges, individual specimens and colorful borders.

The oleander was perhaps not so loved in some areas of the United States in  earlier times as we learn from this entreaty from the Royal palm Nurseries in Florida, circa early 1900's:

So many people, we have found, objected to this subject because they have only been accustomed to seeing great, scraggly, big-caned, ugly specimens in deserted hedge-rows or odd corners, the miserable victims of unpardonable neglect. As a matter of fact, this is one of the very loveliest of all flowering shrubs for general Florida planting and along the Gulf Coast generally and the fact that it will grow in almost any soil and under almost any condition in the state makes it more than doubly valuable. It is truethat it will not be uninjured by cold in the more northerly sections, in severe freezes, but there is considerable difference in the relative hardiness of the different sorts and, even when killed down occa1es right back under good culture and flowers freely as

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before. The following varieties are more hardy than the others: Carneum, Frederick Guibert, Dr. Golfin, Savort, Single White, Dr. Brun.

While not suited for sheared hedge-work, they make splendid informal hedges — a double hedge of white Oleander background with single scarlet hibiscus foreground, or Carneum Oleander with pink Hibiscus foreground, and the like, make wonderfully effective enclosures for formal gardens, as screens for fences, and many other useful purposes. The flowers come in a wide range of color and in great profusion during the spring months, and some sorts bloom more or less throughout the summer. All shades make a splendid effect with the gray-green foliage which, even when there is no bloom, is attractive on properly kept specimens. The great trouble in the case of the Oleander — and indeed with most of our tropical shrubbery — is that the owner does not use the pruning shears! People who in the North would not think of neglecting their shrubs seem to take it for granted that under tropical conditions plants should grow and thrive and look well all the year round and under all conditions without any care. As a matter of fact they should receive as much attention here as elsewhere and under some conditions even more.

As the paragraph above suggests, the oleander is highly adaptable and tolerant of the most difficult conditions, including brackish water and heavy air pollution that would annihilate lesser plants. Epithets such as durable, tough, enduring and indispensable juxtaposed with terms such as splendid, long-flowering and handsome are commonly found in texts that mention the oleander as a mainstay in warm climate gardens throughout the world. Whether utilized as hedges or individually as focal point shrubs, pruned as single or multi-trunk standards, oleanders stand out against a backdrop of sea or sky, quickly cover fences,, hide unsightly buildings, spill over the tops of walls, rapidly form an effective windbreak when planted 3 to 4 feet apart and are perfect companions for small shrubs and perennials. Even when not in bloom, the fine to medium textured leaves are attractive in all seasons, giving the plants a billowy appearance.

Designing with Oleanders

Despite its known toxic qualities, the oleander remains one of the most popular ornamentals for warm climates. Bob Newding, in our interview, gave us extemporaneously  some of the most illuminating insights into designing with oleanders, particularly in Zones 9 and 10 but applicable to seasonal planting in cooler zones as well:

First of all, I think lots of people tend to think about oleanders in monoculture, either as mass plantings along highways or along a border of a parking lot, or maybe as accent plants you might find in someone s yard, and that's it. I like to think of oleanders as part of mixed plantings, mixed with other evergreens, both hardy evergreens and some tropical evergreens. And in doing so, choose the oleanders so that you have in

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the painting . . . tall background plants, plants that tend to be upright, plants that are intermediate-size in the foreground, maybe spreading or weeping varieties, and in the very near foreground possibly having some of the petites and mixing those with hardy evergreens like Pittosporum. And if you want color contrast with a lighter gray-green, there's Eleagnus; if you want texture contrast, the spreading form of the Coppertone Loquat that comes out of California, another Monrovia plant with large, dark green, waxy leaves that tends to mound on itself and has copper-colored new foliage; Sago Palms; even bulbs planted with various ground covers and annual or perennial flowers; Vinca, the Periwinkle, which is in the same family as the oleander and comes in various colors and can compliment the blooms [of the oleander], mixing colors [of oleanders] that go together and in some cases contrast with each other but are broken up by the textures and colors of the other plants that you put with them.

I also mix in plants that have fragrance; the oleanders that have fragrance I mix also with Night-blooming Jasmine and, of course, the Carnation of India is fragrant, especially in the morning when the blooms are fresh they smell somewhat like gardenia. The idea is to use the oleander in combination. If you have a major freeze or you have a problem with disease you can lose a lot of your oleanders, but if you use plants that have different hardiness, different bloom times, you've always got some beautiful oleander that's blooming as an accent, as part of the collage. And even in the winter when they're not blooming, you have the difference in color, texture and the size of the leaves, for instance, in combination with other plants. If one would take the time to study oleanders, [one would find that] oleanders are relatively inexpensive, relatively easy to grow, relatively easy to prune and maintain. I think one of the preferable ways to grow oleanders is in combination with other plants.

Oleanders are commonly seen as hedges used as screens around a yard, as windbreaks in places exposed to constant and often strong winds and to reduce traffic noise, but they are superb when planted as single specimens or as tree forms. (See section on Pruning in Chapter 8.) In fact, they are so versatile that many landscape formats such as massed plantings of mixed species incorporate oleanders of different sizes and flower colors, and on slopes and hillsides they are especially desirable for their full, bushy habit and their fibrous root system which provides excellent erosion control. Of course, for hedges, windbreaks and sound barriers, choose only the most cold hardy varieties.

Ted Turner, Sr. tells us that much of the landscape design currently in vogue in Corpus Christi consists of starting with larger plants as background, then scaling down to an intermediate size and finally to a ground cover type in front. Thanks to the Turners' work in developing more varieties with smaller growth habits, oleanders can play a greater role in this type of landscape design. When the free-blooming petites are mixed with other plants, especially evergreens, and used in the foreground, they are never overbearing and add a splash of color during the summer when other plants are past peak bloom.

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An important observation Bob Newding makes is that oleanders, although salt and wind tolerant and exhibiting no problems growing around Galveston Bay or along the estuaries, often incur serious wind and salt burn on their leaves when planted along the ocean front. He illustrated this by taking me to beachfront planting that were most unsightly because the majority of their leaves were burned and brown with one-third to one-half of the leaf affected. To alleviate this he suggests the following landscape technique:

In planting oleanders on the ocean front with prevailing breezes and salt mist, they must be protected in some way. And, believe it or not, it doesn't mean they have to be planted behind something. Oleanders planted on the ocean front that are right in front of buildings do fine because the wind doesn't blow through the leaves. The physics of the shape of the building behind it changes the wind flow such that the plant is fairly protected. Another way that I recommend is to plant salt tolerant evergreens in front [on the ocean side] of the oleanders such as Pittosporum, for example, then plant the oleanders just on the other side, or downwind from them. The oleanders will actually go up higher than • the Pittosporum so you can see the blooms, but those hardy evergreens will change the flow of the wind so that it comes up over the top of the plants behind them, thereby protecting them. Any time you can create a ramp of plants in front of an oleander planting you will be redirecting the wind flow.

Companion Plants

In addition to the "Family Members" mentioned in Chapter 1 and the suggestions by Bob Newding, there are many possibilities for companion plants in warmer climates. Lantanas — a good choice would be a variety called 'New Gold' for its exceptional flowering qualities — set among rocks around a multi-trunk oleander create a stunning sight with both plants in bloom from spring until fall. Ground cover Sedum spp. are also extremely attractive. In flower beds, street medians and large planters there are many low-growing annual flowers that may be used to create a carpet of any hue to harmonize or contrast with the color of the taller oleander. An idea that is often overlooked is the use of flowering vines as groundcovers. Compact, shrub-form Bougainvilleas make an especially good choice as they will not tend to climb the stems of the oleander and have similar cultural requirements. Literally hundreds of perennial plants and herbs would make colorful and fragrant companions with the only exception being those with very different cultural needs.

Selecting an Oleander for Your Area

The major goal of oleander hybridizing during the past ten years has been development of compact varieties, petite and dwarf forms, and free-blooming c vars, shifting away from utilitarian screens and windbreaks to more ornamental uses.

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There are several factors to consider when choosing an oleander for your garden If you live in a sub-tropical region, you naturally have a much greater choice . because plants can be grown in the ground year round. Nonetheless, ultimate size is ,.n a determining factor, as is growth habit, hardiness, color selection, flower size, ipneth of flowering season and how profusely the plant blooms. If you live in a ..operate area, from the cooler areas of Zone 8 to Zone 4, you will probably want a plant suited for container culture. Although many varieties described in the list of selected cultivars in Chapter 5 will grow well in containers, we would recommend beginning with some of the free-blooming petites or dwarfs. Tree form oleanders are successfully grown in containers in colder areas as well, as long as they are given protection from freezes. If you intend to grow a tree form oleander in the ground in Zone 9 or 10, be certain you have chosen a hardy variety so if you do get a freeze your plant will survive. Remember that if a tree form freezes to the ground it will come back as a shrub! One frost-free area where oleanders do not do well is along coastlines where fog is prevalent much of the year. Here growth is generally thin and leggy and flowering is sparse. Oleanders in hot, humid climates with heavy rainfall such as southeast Asia often have a difficult time performing at their best. Interestingly, many sources agree that the double-flowered varieties provide a better display than the single-flowered types in situations such as these where conditions are less than ideal.

In speaking with Dr. Jerry Parsons, I learned some interesting facts about the San Antonio, Texas, area. Since no one can exactly paraphrase Dr. Parsons and do him justice, we quote in full:

You see, there's not really that much work being done with oleanders. It's a very underused plant, mainly because nobody's interested in it north of here, because it will freeze. Of course, we've got a situation here. A lot of people don't realize it in these urban areas, but one of the big problems we have is deer. The deer population is just terrible. And somebody calls and says, "I want an evergreen shrub for a screen that's green all winter and that blooms in the summer and is drought tolerant. What can I plant that the deer won't eat?" Well, what is that? It's the oleander. And people say, "I don't like the oleander." Well, you better learn to like the oleander, its the only damned thing you've got to plant out there. They'll [the deer] eat the hell out of everything else!... they'll eat the first new leaves of an oleander in the spring but they don't eat 'em very long!

Growing Oleanders in the Ground in Temperate Climates

We are fortunate to have the experiences of Clarence Pleasants as guidelines r growing oleanders in the ground as far north as Norfolk, Virginia. During his years at the Norfolk Botanical Garden, he developed a thorough knowledge of oleander cultivation in an area that, during the 1950's and 60's recorded average low , Features in the upper 20's and rarely dipped below 19°, and then only for a few 's. Freezing temperatures in this range would last for several days and would

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occur every 2 to 3 years. Oleanders might grow to a height of 6 or 8 feet and then a freeze would kill them to the ground, thereby limiting their ultimate size. As Clarence said, "Mother Nature did the pruning."

In temperate climates full sun exposure is even more critical for plants to flower well. Clarence observed that the best locations were against a wall or building where they were exposed to maximum sunlight and heat and protected from the wine} During the years he collected cuttings from the eastern part of the United States, he noticed significant differences in cultivars with some varieties much more wind tolerant than others and a few displaying greater cold tolerance than those commonly grown in the area. A fascinating report (appearing in a recent issue of Nerium News) is from an enthusiast in Villas, New Jersey, who has been growing oleanders for about 35 years and has amassed a collection of several thousand plants. Even more astounding is that he is growing them out of doors in the ground year-round! Located near the southern tip of Cape May County near the Atlantic Ocean and only blocks from Delaware Bay, he finds the location to be a microclimate with conditions similar to Zone 8 or 8B and is also able to grow other relatively tender plants such as palms and gardenias without winter protection.

Oleanders are often grown in large tubs in the Norfolk area, usually planted in heavy clay soil. Gardeners would tell Clarence how much work it was to move plants indoors in fall and out again in the spring. (This is another reason to grow oleanders in lightweight, highly organic soil mixes!) For oleanders grown in the ground, Clarence recommended the addition of organic matter for root development and good drainage but cautioned that in colder areas overly rich soil conditions should be avoided. It was his contention that if plants are discouraged from growing rapidly and putting on extensive growth they will go dormant earlier and increase in-hardiness.

Oleanders Grown as Annuals in Colder Areas

Oleanders are excellent grown as annuals in areas too cold for successful overwintering or if one hasn't a greenhouse or sunroom in which to keep them throughout the winter months (or a desire to haul them in and out of a cellar). The dwarf and petite forms are especially good choices as they are very early to bloom and with regular care and fertilizing will continue until the first frost. There are not many exotic plants that will flower for such a length of time and the cost of an oleander is in the same range as many tropical hibiscus which are often treated as annuals parks and gardens in the north.

I never saw a garden from which

I did not learn something.

Page Russell,

The Education of the Gardener

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The petite oleander. Carnival, flanked by companion plants From left Cestrum nocturnum (Night-blooming Jasmine) in heavy bud, Cycas revoluta (Sago Palm), Tabernaemontana divaricata (Crepe Jasmine, Carnation of India), photographed at Bob Newding's home.

Some Sources for Oleanders

Retail

Numerous retail nurseries and garden centers throughout the u.s. offer oleander plants during spring and summer.

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