Flamingo Japanese willow shrubs offer nice stem and foliage color in spring. However, they can be a lot of work considering that they lack year-round interest. Inform yourself of the qualities of these bushes before you decide whether to take the plunge and grow one.
Taxonomy and Botanical Type for Japanese Willows
Plant taxonomy classifies the Japanese willows (or "dappled willows") dealt with here as Salix integra Flamingo.
The cultivar name, Flamingo, refers to the pink color contained in some of the plants' new leaves at the tips of the branches. "Flamingo willow" is another common name for Salix integra Flamingo.
Plant Qualities, Landscape Uses
Flamingo willows are fast-growing shrubs with good leaf and stem color. Color may be better if shrubs are pruned regularly. These shrubs are foliage plants; they are not grown for their flowers, which are insignificant and appear on catkins (as with pussy willow). The attraction in growing Japanese willows is in their variegated leaves. But this is not just a plant with two-toned leaves; in spring, it is a tri-colored variegated plant, although not as striking as tricolor beech. Older leaves in spring are merely dappled (light green and white), but new leaves may contain a bit of pink. New branches display a red color, especially in spring.
They stand 6 feet tall or more (with a similar spread) at maturity if left unpruned, but you will almost surely want to prune them to maximize their coloration.
USDA Plant Hardiness Zones, Sun and Soil Needs
These shrubs are easy to grow and are not fussy about soil, although they prefer somewhat wet ground (but not constantly soaked) enriched with soil amendments. Add humus at planting time and supplement periodically thereafter with compost. Plant in a location with full sun. While these bushes can survive in partial shade, it is only in full sun that they will achieve their best color. Apply mulch to retain moisture.
Other Types of Willow
If you know someone who grows a Japanese willow, there is a very good chance that it is not the Flamingo type but, rather, Salix integra Hakuro Nishiki, which has been around longer. In fact, Flamingo is a sport (mutation) of Nishiki. Flamingo's color is supposed to be superior to that of Nishiki.
In addition to Japanese willows, there are other trees and shrubs in the Salix genus that are popular in landscaping. Just remember that, generally, Salix is not the genus you want to plant around septic systems, underground pipes, etc. The most famous are:
- Weeping willow (Salix babylonica)
- Pussy willow (Salix discolor)
- Goat willow (Salix caprea, the Old-World version of North America's pussy willow)
But besides these well-known trees and shrubs, related plants that have cultivars useful in landscaping are (all grow best in zones 4 to 8, in an area with full sun and moist soil):
- Salix alba
- Salix gracilistyla
- Salix matsudana
Salix alba's common name is "white willow," but it's the more colorful cultivars that are of the most interest. Coral bark willow (Salix alba subsp. vitellina Britzensis) is one of the best. Its new stems have an orange-red color in late winter. They can be even more colorful than those of red-twig dogwood (Cornus alba). Technically, this is a tree that would become up to 80 feet tall and 50 feet wide over time, but gardeners usually prune it back heavily every year to keep it shrub-like. Such pruning produces lots of the colorful new stems that give the plant its value. Prune the plant down to within 1 foot of the ground in late winter, then await the emergence of that colorful display so needed for winter interest in the Northern yard.
Salix gracilistyla is commonly called the "rosegold pussy willow" because the catkins on the male, which start out like regular pussy willows, later turn to pinkish, then orange, and, finally, yellowish.
Of even greater interest to those who enjoy using pussy willows in floral arrangements is the Melanostachys cultivar, which has catkins so dark that the bush is sometimes called the "black pussy willow." Both rosegold and Melanostachys are shrubs that become about 10 feet x 10 feet at maturity.
Salix matsudana has cultivars with twisted branches that go by such apt names as Tortuosa, Scarlet Curls, and Golden Curls. These are trees that grow 30 to 40 feet high.
Flamingo Can Be Somewhat High-Maintenance to Grow
There are lots of variations in the color of Japanese willow shrubs, some living up to the colorful name, "Flamingo," others having a rather mediocre coloration. As with many plants, such issues may be influenced by any of a number of factors, for example, how and how much you prune them, hours of sunlight received, watering, and soil conditions.
Trying to coax superior coloration via pruning means having to remember to perform the task, which is a problem for many gardeners. In fact, because it's a vigorous grower, Flamingo would not be considered a low-maintenance plant (if you're looking for a compact shrub) even if you didn't care about achieving optimal color: You would still have to prune it just to keep it within bounds. You may be motivated to prune in summer simply because its leaves at that time of year are not very attractive (green leaves predominate at this time, with variegated leaves taking a back seat).
Care for Japanese Willows
If left unpruned, the branches will assume more of an arching habit. But it should not be allowed to get that big. What you would gain in mass and gracefulness, you would lose in color, potentially. To achieve the best color, fertilize Japanese willows and maintain the following pruning regimen for them:
- Prune heavily in early spring, when still dormant.
- Prune again in late spring to early summer.
- Prune again in August.
Cut 1/3 of the older branches right down to the ground in spring, and trim back the top growth (remove a foot or so) on the remaining branches.
New shoots will emerge to take their place. You can even experiment with more drastic pruning because the Salix genus is very tolerant in this regard. This pruning advice pertains to growing Japanese willows as multi-branched shrubs. If you grow the plant as a standard (small tree), you will, of course, be unable to do such drastic pruning, as you will have only one main branch with which to work. But standard-growers will still be able to trim back the upper branches twice a year or more, to keep encouraging the development of fresh vegetation.
The idea behind all of this pruning is to generate new growth. It is the new growth that is most colorful. As a result of the last pruning you do in late summer, growers in warmer areas may be able to enjoy red stems on their Japanese willow during the winter, not unlike what you would expect from redtwig dogwood. Even in cooler areas, winter color might be a bit better on newer wood than on older. But the critical pruning is the one done in early spring. To help yourself to remember to perform this task, add it to your list of spring cleaning chores for the yard.