Powdery Mildew-Resistant Woody Ornamentals
ID
450-616
Powdery mildew is a common fungal disease of many ornamental plant species. Although plants are not often killed by the disease, they may become unsightly when heavy fungal growth develops on leaves and flowers. Controlling the disease on susceptible plants usually requires multiple sprays of an appropriate fungicide. Use of resistant cultivars in new plantings can significantly reduce plant maintenance related to powdery mildew control. Assembled below are lists of species, cultivars, and/or hybrids of some of the more popular woody landscape plants that are reported to have resistance to powdery mildew (Tables 1-5). This information was compiled from several different landscape and field studies in which resistance to powdery mildew was evaluated.** Although the exact level of powdery mildew resistance exhibited by an individual cultivar may vary depending on where the plant is grown, all the plants listed should have moderate to excellent resistance and a reduced need for fungicide sprays. For more information on powdery mildew, refer to VCE Publication 450-603W, Powdery Mildew of Ornamental Plants.
| Table 1. Powdery mildew-resistant dogwood cultivars | ||||
|---|---|---|---|---|
Flowering Dogwood (Cornus florida) Rutger's Hybrids (Cornus florida x Cornus kousa) | Kousa Dogwood (Cornus kousa) Angustata Autumn Rose Benji Fuji Big Apple Blue Shadow China Girl Chinensis Bodnant Doubloon Emerald Star Form Gay Head Greensleeves Hart #3 Julian Milky Way | Milky Way Select Miss Satomi Moonbeam National Radiant Rose Rochester Snow Flake Speciosa Summer Majesty Sunsplash Temple Jewel Trinity Star Triple Crown Weavers Weeping Wilton Wolf Eyes | ||
| Table 2. Powdery mildew-resistant rose cultivars | ||||||||
|---|---|---|---|---|---|---|---|---|
Floribundas Grandifloras | Hybrid Teas Bobby Charlton Bride's Dream Canadian White Star Cary Grant Chablis Dainty Bess Duet Electron Elina Elizabeth Taylor Elmhurst Folklore Helmut Schmidt Keepsake Konrad Henkel Lady Lady Rose Lady X Las Vegas Maid of Honor Mikado Miss All American Beauty | Modern Art Miniatures | Anytime Beauty Secret Black Jade Centerpiece Cinderella Cuddles Deep Velvet Ginny Green Ice Heartland Jean Kenneally Jennifer Kathy Robinson Linville Loving Touch Magic Carrousel Mary Bell Minnie Pearl Old Glory Peacesetter Puppy Love Queen City Red Flush Simplex | Singles Better Shrub Roses | ||||
| Table 3. Powdery mildew-resistant lilacs (Syringa species and hybrids) | ||
|---|---|---|
| S. diversifolia S. emodi S. henryi 'White Summers' S. josiflexa 'Anna Amhof' S. josiflexa 'Royalty' S. julianae S. meyeri 'Palibin' S. microphylla S. microphylla 'Superba' S. oblata var. dilatata | S. patula 'Miss Kim' S. persica (=S. x persica) S. refexandowii S. reticulata 'Summer Snow' S. swegiflexa (=S. x swegiflexa) S. villosa S. yunnanensis S. x prestoniae 'Donald Wyman' S. x prestoniae 'James McFarlane' S. x prestoniae 'Minuet' | |
| Table 4. Crape myrtle cultivars tolerant or resistant to powdery mildew | ||||||||
|---|---|---|---|---|---|---|---|---|
| Cultivar | Flower | Twig/Bark/Inner Bark | Fall Color | Form | ||||
| Acoma | white | purple/brown/lt gray | orange | semi-dwarf | ||||
| Apalachee | lt lavender | red/gray brown/cinnamon | dull orange | upright lg shrub | ||||
| Biloxi | pale pink | gray brown/dk brown | yellow to red | tree | ||||
| Catawba | dk purple | tan/buff | orange-red | globose | ||||
| Cherokee | bright red | - | - | globose | ||||
| Comanche | coral pink | brown/gray brown/ gray orange | dk orange to dk purple | sm tree | ||||
| Hopi | pink | red/gray brown/lt gray | orange-red | shrub | ||||
| Lipan | med lavender | red purple/gray/green-mottled white | orange | upright shrub | ||||
| Miami | dk pink | gray brown/gray green/ dk brown | orange to red | tree | ||||
| Muskogee | lt lavender | med brown | red | sm tree | ||||
| Natchez | white | dk cinnamon | orange | shrub/sm tree | ||||
| Osage | pink | red purple/gray brown/ chestnut brown | red | sm tree | ||||
| Pecos | pink | red/gray/dk brown | maroon | globose shrub | ||||
| Powhatan | lt lavender | - | - | globose | ||||
| Seminole | pink | - | - | globose | ||||
| Sioux | dk pink | dull red/gray brown/ lt gray brown | maroon to red | upright sm tree | ||||
| Tuscarora | dk coral pink | lt brown | orange-red | sm tree | ||||
| Tuskegee | dk pink-red | gray/tan | orange-red | broad | ||||
| Wichita | lt magenta | red purple/gray/ dk mahogany | russet/ mahogany | tree | ||||
| Yuma | med lavender | red purple/gray/lt gray | yellow to orange | sm tree | ||||
| Zuni | med lavender | red/gray/lt brown | dk red | semi-dwarf | ||||
| Table 5. Powdery mildew-resistant crabapple cultivars | ||||||
|---|---|---|---|---|---|---|
| Cultivar | Bud/Flower Color | Fruit Color | Form | |||
| Adirondack | carmine/white | orange-red | sm columnar | |||
| Ames White | pink/white | yellow | round | |||
| Autumn Glory | red/white | orange-red | upright | |||
| Baskatong | dk red/lt purple red | dk purple red | tree | |||
| Beauty | rose pink/white | dark red | fastigiate | |||
| Coral Cascade | coral red/white | coral pink | med weeping | |||
| David | pink/white | scarlet | round | |||
| Donald Wyman | pink/white | bright red | upright | |||
| Gibb's Golden Gage | pink/white | yellow | sm rounded | |||
| Golden Raindrops | pink/white | golden yellow | sm rounded | |||
| Gwendolyn | pink/pink | red | - | |||
| Harvest Gold | white/white | gold | upright | |||
| Indian Summer | red/rose red | red | broad/globe | |||
| Molten Lava | red/white | red-orange | spread wide/weeping | |||
| Mount Arbor Special | carmine/pink | red | - | |||
| Naragansett | red/white | cherry red | small rounded | |||
| Prariefire | red/dk red | red-purple | rounded | |||
| Professor Sprenger | pink/white | yellow-pink | upright-spreading | |||
| Purple Prince | carmine/red | bl-purple | rounded | |||
| Red Snow | orange-red/pink | bright red | sm arching | |||
| Tina | red/white | red | dwarf, low spreading | |||
| Wies | pink/pink | dark red-purple | upright | |||
**The information presented in Tables 1-5 was complied from surveys and field trials conducted in Tennessee, Maryland, and North Carolina between 1990-1996. Information from a 1980 crabapple survey conducted in Pennsylvania is also included.
Selected References
Dirr, M. A. 1998. Manual of Woody Landscape Plants, 5th ed. Stipes Publishing, Champaign, IL. 1187 pp.
| Disclaimer Commercial products are named in this publication for informational purposes only. Virginia Cooperative Extension does not endorse these products and does not intend discrimination against other products which also may be suitable. |
Rights
Virginia Cooperative Extension materials are available for public use, re-print, or citation without further permission, provided the use includes credit to the author and to Virginia Cooperative Extension, Virginia Tech, and Virginia State University.
Publisher
Issued in furtherance of Cooperative Extension work, Virginia Polytechnic Institute and State University, Virginia State University, and the U.S. Department of Agriculture cooperating. Alan L. Grant, Dean, College of Agriculture and Life Sciences; Edwin J. Jones, Director, Virginia Cooperative Extension, Virginia Tech, Blacksburg; Jewel E. Hairston, Administrator, 1890 Extension Program, Virginia State, Petersburg.
Date
May 1, 2009