Bridal wreath spirea (Spiraea prunifolia) is a medium-sized deciduous shrub with an upright arching habit, featuring thick sprays of white double flowers that create a focal point in the landscape. In the spring blooming season, bridal wreath spirea creates a cascading waterfall of white, with clusters of small white flowers that bloom all the way down the arching stems that have not yet developed leaves. The flowers are followed by 1- to 3-inch-long oval leaves, which transition to attractive hues of yellow-orange or purplish brown in the fall.
Spirea is a fast-growing shrub, and it usually achieves full size within a single growing season. Like many shrubs, this native of China, Korea, and Taiwan is best planted early in the growing season as a container-grown nursery plant, which will allow the shrub's root system plenty of time to become established before winter. If you must plant in the fall (this sometimes is when nurseries are discounting available stock), try to do it with enough time so the shrub's roots can settle in and begin growing before winter weather sets in.
|Common Name||Bridal wreath spirea|
|Botanical Name||Spiraea prunifolia|
|Plant Type||Deciduous shrub|
|Mature Size||4-8 ft. tall, 4-8 ft. wide|
|Soil pH||Acidic, neutral|
|Hardiness Zones||4-9 (USDA)|
Bridal Wreath Spirea Care
This shrub is very easy to grow in any average soil in a full sun location. It will tolerate some shade, and once established, it has a decent tolerance for occasional drought. Like most shrubs, it should be planted in a carefully prepared hole, at the same depth it was growing in its nursery pot. If planting in a row or mass, space the plant at least 3 feet apart, or 4 to 6 feet apart for a looser mass.
Although Spiraea prunifolia is not included on any state lists of dangerously invasive plants, it has been known to accidentally naturalize in some regions. Planting of any spirea should be done cautiously, as many types—such as Japanese spirea (S. japonica)—are recognized as being invasive. Keep in mind that bridal wreath spirea is not a native North American plant, and as such should not be planted where it might accidentally naturalize into wild areas.
This shrub will do best in a spot in your garden that receives full sun; it will tolerate part shade, though with slightly reduced flowering. When planting young bridal wreath spirea shrubs, make sure to provide plenty of room between them: They will grow and can block each other's light if planted too close together.
This plant is not picky about the soil it's planted in, and can thrive in clay, loam, and even acidic soils. Its biggest need is soil that's well-draining, so the roots never sit in water.
Bridal wreath spirea prefers to grow in well-drained moist soil, though it is able to withstand some periods of drought. Water the plants once a week during the summer whenever rainfall is less than 1 inch. Keep the plants well-watered as they are becoming established—that is to say, for the first full growing season after planting them.
Temperature and Humidity
This plant is quite hardy, surviving both cold winter and hot summer temperatures in its defined range. It thrives in any climate conditions within its USDA hardiness zones (4 to 9). It has no preference for humidity conditions.
Every spring, add a 2-inch layer of compost over the soil under the shrub. This is usually sufficient to feed the plant, and it will also help to retain moisture and prevent weeds. Additional fertilizing is not necessary, and may even reduce flowering.
Types of Bridal Wreath Spirea
- The bridal wreath spirea offered for sale is usually S. prunifolia 'Plena'. The pure species, as well as a a naturally occurring single-flowered form (Spiraea prunifolia var. simpliciflora) are rarely found for sale. Spiraea prunifolia is a very old landscape specimen, in cultivation since 1864 and regarded by some as inferior to modern cultivars. But it can still be a very dependable and easy-care shrub for more informal landscapes, and it is often seen around farmhouses and rural residences.
- The common name "bridal wreath" is also sometimes applied to a hybrid shrub, Spiraea x vanhouttei, which is a cross between S. trilobata x S. cantoniensis. This hybrid is very similar to S. prunifolia, but is a somewhat larger specimen, growing as much as 12 feet across, and is hardy to zone 3. It is a very common nursery offering. There are several good cultivars of S. x vanhoutttei, including 'FiregoldTM', 'Gold Fountain', and 'Pink Ice.'
This plant tends to spread through suckering, so ground suckers will need to be trimmed off if you want to keep the shrubs confined.
If desired, the shrubs can be pruned for shape or size immediately after the spring flowering period. Always use clean, sharp pruning shears. A good pruning routine is to remove all dead wood, as well as some of the oldest stems all the way to ground level. This will open up the center of the shrub to sunlight to reinvigorate it. Tips of branches can also be trimmed to control the size of the shrub.
Propagating Bridal Wreath Spirea
The best way to propagate bridal wreath spirea shrubs is by rooting softwood cuttings during the active growing season. To do so:
- Cut segments of flexible stem tips 6- to 8-inches long. Remove the bottom leaves from these trimmed segments. Dip the cut end into powdered rooting hormone.
- Fill a 6-inch pot with moist potting mix, then plant four or five prepared stems around the inner edge of the pot, embedding the exposed nodes into the potting mix. Cover the pot with a large plastic bag and seal it.
- Place the pot in a dappled shade location and allow the cuttings to root over the next few weeks. Check periodically to make sure the potting mix remains moist.
- After about four weeks, you should see new, green growth on the stems, indicating that roots are forming. At this point, repot the cuttings into their own individual containers, then tuck the pots into a sheltered location and allow them to continue growing until they go dormant in winter. The next spring, transplant the rooted cuttings into the garden. It generally takes no more than a single year in the pot before these plants are ready for garden use.
Remember that it is technically illegal to propagate trademarked or patented cultivars. If you are planting a named cultivar, check the plant labels for indications that the plant has been granted or is pending any kind of copyright protection. If so, it should not be propagated in any way.
How to Grow Bridal Wreath Spirea From Seed
Although not common, seed propagation is possible. It's best to sow the seeds collected from seed clusters in the spent flowers immediately after you collect them. But seedlings will take several years to grow into mature landscape plants, which is the reason why propagation is usually through vegetative means, such as softwood cuttings (see above).
These hardy shrubs generally require no winter protection against cold. Their spiny stems make them fairly resistant to deer browsing, but rabbits sometimes nibble on them when the plants are young, so a protective screen of wire mesh is a good idea for young shrubs.
Common Pests & Plant Diseases
There are no serious pest or disease problems for the bridal wreath spirea, but they can be mildly susceptible to many of the diseases and insects that attack other members of the rose family. These include leaf spot, fire blight, powdery mildew, root rot, aphids, leaf roller, and scale.
How to Get Bridal Wreath Spirea to Bloom
Bridal wreath spirea typically blooms robustly in spring before the stems leaf out. The flowers are small, grouped in clusters of three to six, white with a tinge of green. Flowering is minimal with new shrubs, but after a year you should experience good flowering, provided the shrub is getting plenty of sunlight.
This is not a plant that blooms more robustly if you fertilize it. In fact, excessive fertilizer may well lead to fewer flowers. Pruning at the wrong time can also remove the flower buds and cause a temporary loss of flowers. These shrubs bloom on the previous year's wood, so they should be pruned immediately after they flower. If you prune too late in the fall or in early spring, you likely will be removing the stems containing the buds that will produce spring flowers.
Common Problems With Bridal Wreath Spirea
Bridal wreath spirea is a mostly care-free plant, The chief complaint, mostly among gardeners who haven't researched the plant before choosing it, is that it can be a somewhat shaggy, unkempt shrub—not the elegant, cascading plant they are expecting from a spirea. If you want that kind of shrub, you are better off planting one of the S. japonica cultivars or hybrids. Bridal wreath spirea is a better choice for large yards where you need an easy-care background shrub that provides a natural, woodsy transition to adjoining property.
How should I use this plant in the landscape?
Bridal wreath spirea makes a great specimen plant set at the back of a large yard, or planted in masses as a screen. It also works well in foundation plantings for large homes, such as farm-house style residences, but should be kept well away from entrances. It is excellent when planted in the sunny margins abutting woodland areas, similar to the way azaleas are often used. Make sure to plant this shrub where it will not scratch human passers-by—unless you are planting it with the intention of discouraging intruders.
How long does bridal wreath spirea live?
This shrub can happily live in a favorable location for many decades. Hundred-year-old specimens are common, and are plentiful around historical farmhouses across the Midwest and East.
What about wildlife?
Although no shrub is entirely safe from browsing by hungry deer or rabbits, the thorny nature of spirea (it is a member of the rose family) makes it largely free of serious damage from creatures. However, when young, the shrubs can be susceptible to serious browsing by rabbits. And this shrub is very attractive to butterflies and other pollinators during its bloom season. Its dense growth habit and thorny protective stems make it a favorite nesting spot for small birds.
Are there any native plant alternatives to bridal wreath spirea?
If you prefer a native white-flowering species, try Spiraea alba, a native plant of the Eastern U.S. and Midwest. It grows to about 4 feet tall, flowers in summer, and is hardy to zone 3.
Is there a bridal wreath spirea with colored flowers?
No. This is a white-flowered species. Most spireas with colored flowers (usually pink or purple) are cultivars of S. japonica, Japanese spirea.
Dirr, Michael. Spiraea prunifolia. Dirr's Encyclopedia of Trees & Shrubs. Timber Press, 2011.
Japanese Spiraea. USDA National Invasive Species Information Center.
Dirr, Michael. Manual of Woody Landscape Plants, Stipes Publishing, 1998..