Culture
Multiflora rose is classified as a noxious weed in the State of Missouri. It may not be sold in commerce, and each Missouri county has the authority to adopt programs requiring mandatory control of the plant. The plant grows best in deep, fertile, medium moisture, well-drained soils in full sun. Best flowering and disease resistance occur in full sun. Plants have better tolerance for some shade than most other types of roses. Consistent moisture (avoid overhead watering), good air circulation and summer mulch help promote best growth.
Noteworthy Characteristics
Rosa multiflora, called multiflora rose, is native to Japan and Korea. It is a rambling rose that is noted for its arching and spreading habit. It was first introduced into the U. S. in 1886 for use as a rootstock for cultivated roses. In the 1930s, the U.S. Soil Conservation service began encouraging use of the rose to fight soil erosion. It also became popular both for fence rows to control livestock and for wildlife cover. Unfortunately this rose turned out to be much more invasive than originally thought, and it has over time naturalized throughout many rural areas in the eastern and central U.S., forming dense impenetrable thickets that tend to eliminate native plants and in some cases render land virtually unusable. It is today considered to be a serious weed problem for agricultural/rural areas such as pastures, fields and unplowed land. Multiflora rose spreads through self-seeding, root sprouts and arching stems that root in the ground. Plants feature coarse, prickly, arching canes that typically can grow to 15’ tall. Small (.75 to 1.5” across), aromatic, white to light pink roses in pyramidal to globular clusters (to 30 flowers per cluster) explode into bloom in one profuse June display. Flowers give way to small red hips (to 3/8” long) in early fall which persist into winter. Pinnately compound, medium green leaves typically have 7-9, toothed, oval leaflets each. Common name and specific epithet are in reference to the prodigious flowering.
Genus name comes from the Latin name for rose.
Specific epithet means many-flowered.
'Grevillei', called seven sisters rose, is a multiflora hybrid rambler which is an extremely vigorous, spreading shrub with coarse, arching canes typically growing to 15' tall. Features small, variably colored, fragrant flowers in clusters (25-30+ flowers per cluster) which explode into bloom in one profuse June display. No repeat bloom. Flowers open purple and progress through various stages of bloom (purple to lilac to pink to almost white). Wrinkled, light green foliage. Flowers give way to small red hips which persist into winter. Synonymous with and formerly known as Rosa multiflora 'Platyphylla'.
Problems
Roses are generally susceptible to a large number of disease problems, the most common of which are black spot, powdery mildew and rust. Although good cultural practices are the first line of defense in disease control, regular preventative fungicide applications throughout the growing season are often required, particularly in humid climates with regular rainfall such as the St. Louis area. Watch for rose rosette, which requires more aggressive action. Potential insect problems include aphids, beetles, borers, scale, thrips, leafhoppers and mites. Invasiveness is a serious problem. See "Notice" below.
Uses
This rose should not be planted or grown in the State of Missouri, except when grown or used solely as an understock for cultivated roses.