Powdery Mildew
Podosphaera aphanis var. aphanis
598 host plants · Fungal
Last updated
Data Coverage 3 of 6 dimensions
A white or grayish powdery coating on leaves and stems is your first sign, starting on younger, developing foliage in summer and reaching peak severity in late summer. Unlike most fungal diseases, powdery mildew thrives in warm, dry conditions with high humidity (60-80% RH) but no free moisture on leaf surfaces, making it a problem even during dry spells. Young tissue is susceptible; as leaves mature, they become resistant. Look for tiny black pepper-like fruiting bodies embedded in the white mycelium by late season.
Powdery mildew weakens plants through reduced photosynthesis and can cause premature leaf drop, setting back flowering the next year. The disease spreads wind-blown, so dense plantings and poor air circulation are your biggest risk factors. Your primary defense is spacing plants widely for air movement and avoiding afternoon shade in the landscape. Resistant cultivars exist for many hosts like apples and crabapples. Early pruning of infected terminals and removing too many leaves damages the tree more than the disease itself, so resist the urge to aggressively prune.
Quick Reference
Agent Type
fungal
Causal Agent
Podosphaera aphanis var. aphanis
Host Plants
598
Spread
wind
Favorable Conditions
Favored by warm days (60–80°F), cool nights, high humidity (>60% RH); does NO...
Management
Vulnerability Window
Summer through fall; peak severity in late summer; youngest foliage most susceptible
What Triggers Infection
Favored by warm days (60–80°F), cool nights, high humidity (>60% RH); does NOT require free water on leaf surface unlike most fungi. Suppressed by temperatures >95°F and direct rainfall (PNW Gardeners Handbook Ch 17, 23).
Cultural Controls
- Disease-resistant cultivars of C. florida include Karen's Appalachian Blush, Jean's Appalachian Snow, Kay's Appalachian Mist, and Appalachian Joy.
- The C. kousa x florida hybrids 'Aurora', 'Constellation', 'Galaxy', 'Stardust', and 'Stellar Pink' are highly resistant.
- Improve air circulation to reduce relative humidity and accelerate drying of foliage.
- Space plants well and plant in more exposed areas; especially avoid planting in heavily shaded areas.
- Irrigate with microjet sprinklers or soaker hoses to avoid wetting foliage.
- If practical, prune out and destroy infected tissue as it appears early in the year.
Host Plants (598)
Acer buergerianum Trident Maple, Three-toothed Maple Acer campestre Hedge Maple, Field Maple, Common Maple Acer capillipes Red Stripebark Maple, Red Snakebark Maple, Hakkoda Maple Acer carpinifolium Hornbeam Maple Acer circinatum Vine, Maple Acer coriaceifolium Leatherleaf Maple Acer crataegifolium Hawthorn, Maple Acer davidii David Maple, Père David's Maple Acer freemanii Freeman Maple, Hybrid Red Maple Acer ginnala Acer ginnala Acer glabrum Rocky Mountain Maple, Rock Maple, Douglas Maple, Dwarf Maple Acer glabrum var. douglasii Douglas Maple, Dwarf Maple, Rocky Mountain Maple Acer grandidentatum Bigtooth Maple, Western Mountain Sugar Maple, Rocky Mountain Sugar Maple Acer griseum Paperbark Maple Acer henryi Henry's Maple Acer japonicum Fullmoon Maple Acer macrophyllum Bigleaf Maple Acer maximowiczianum Nikko Maple Acer miyabei Miyabe Maple Acer monspessulanum Montpellier Maple Acer negundo Boxelder Manitoba Maple, Ash-leaved Maple Acer nipponicum Nippon Maple Acer oblongum Evergreen Maple, Smooth Leaf Maple Acer oliverianum Oliver Maple Acer opalus subsp. obtusatum Bosnian Maple Acer palmatum Japanese Maple Acer palmatum var. dissectum Dissected Japanese Maple Acer pensylvanicum Striped Maple, Moosewood Maple Acer pentaphyllum Acer pentaphyllum (no common name) Acer pictum Painted Maple Acer platanoides Norway Maple Acer pseudoplatanus Planetree Maple, Sycamore, Maple Acer rubrum Red Maple Acer rufinerve Redvein Maple, Honshu Maple Acer saccharinum Silver Maple Acer saccharum Sugar Maple Acer sempervirens Cretan Maple Acer shirasawanum Shirasawa Maple Acer spicatum Mountain Maple, Moose Maple Acer tataricum Tatarian Maple, Tartarian Maple Acer tataricum subsp. ginnala Amur Maple Acer tegmentosum Manchurian Stripebark Maple, Manchustriped Maple Acer triflorum Three Flowered Maple Acer truncatum Purpleblow Maple, Shantung Maple Acer velutinum Velvet Maple Adenium obesum Desert Rose, Desert Azalea, Mock Azalea Aesculus californica California Buckeye, California Horsechestnut Aesculus chinensis Chinese Horsechestnut, Chinese Buckeye Aesculus flava Yellow Buckeye, Sweet Buckeye Aesculus glabra Ohio Buckeye, Fetid Buckeye Stinking Buckeye Aesculus glabra var. arguta Texas Buckeye, White Buckeye Aesculus hippocastanum Horse Chestnut Aesculus parviflora Bottlebrush Buckeye Aesculus pavia Red Buckeye, Red-flowering Buckeye Aesculus sylvatica Painted Buckeye, Georgia Buckeye Allium Tapertip Onion Alnus alnobetula Circumpolar alder group Alnus alnobetula subsp. crispa American Green Alder, Mountain Alder, Green Alder Alnus alnobetula subsp. sinuata Sitka Alder, Wavy Leaf Alder Alnus cordata Italian Alder Alnus glutinosa Common Alder, European Alder, Black Alder Alnus incana subsp. rugosa Speckled Alder Alnus incana subsp. tenuifolia Thinleaf Alder, Mountain Alder Alnus japonica Japanese Alder Alnus rhombifolia White Alder Alnus rubra Red Alder Alnus rubra f. pinnatisecta Cutleaf Red Alder Alnus sinuata Sitka Alder Aquilegia Columbine Arbutus unedo Strawberry Tree, Killarney Strawberry Tree, Madroño Asimina triloba Common Pawpaw Custard Apple Aster Alpine Aster Begonia Hardy Begonia Berberis aquifolium Oregon Grape, Oregon Grape Holly, Tall Oregon Grape Berberis buxifolia Berberis buxifolia Berberis darwinii Darwin Barberry Berberis emerald Berberis emerald Berberis fremontii Fremont Barberry, Fremont Mahonia Berberis gladwynensis Berberis gladwynensis Berberis jamesiana James Barberry Berberis julianae Wintergreen Barberry Berberis mentorensis Mentor Barberry Berberis nervosa Longleaf Mahonia Cascade Mahonia Berberis pinnata California Barberry, California Holly Grape Berberis pruinosa Pruinosa Barberry Berberis repens Creeping Mahonia Berberis replicata Evergreen Barberry Berberis stenophylla Rosemary Barberry Berberis thunbergii Japanese Barberry Berberis thunbergii var. atropurpurea Purple (Red) Leafed Japanese Barberry Berberis triacanthophora Threespine Barberry, Wisley Barberry Berberis verruculosa Warty Barberry Betula lenta Sweet Birch, Cherry Birch, Black Birch Buddleia davidii Butterfly Bush, Summer Lilac Centaurea montana Mountain Bluet or Perennial Cornflower Chrysanthemum coccineum Chrysanthemum Clematis armandii Evergreen Clematis, Armand Clematis Clematis cirrhosa var. balearica Fern-leaved Clematis Clematis hybrid Hybrid Clematis Clematis montana var. rubens Pink Anemone Clematis Clematis tangutica Golden Clematis Clematis terniflora Sweet Autumn Clematis, Sweet Autumn Virginsbower, Leatherleaf Clematis, Japanese Clematis Clematis viticella Italian Clematis Cornus alba Tatarian Dogwood, Tartarian Dogwood Cornus alternifolia Pagoda Dogwood Cornus amomum Silky Dogwood Cornus canadensis Bunchberry Cornus capitata Evergreen Dogwood, Bentham's Cornel, Himalayan Strawberry Tree Cornus controversa Giant Dogwood Cornus drummondii Rough-leaved Dogwood Cornus eddies Cornus eddies Cornus elwinortonii Cornus elwinortonii Cornus florida Flowering Dogwood Cornus kousa Kousa Dogwood Cornus mas Corneliancherry Dogwood Cornus nuttallii Pacific Dogwood Cornus officinalis Japanese Cornelian Dogwood Korean Cornelian Dogwood, Chinese Cornelian Dogwood Cornus porlock Porlock Dogwood Cornus racemosa Gray Dogwood, Red Panicle Dogwood Cornus rutgersensis Cornus rutgersensis Cornus sanguinea Bloodtwig Dogwood Cornus sericea Cornus sericea Cornus sericea subsp. occidentalis Western Dogwood, Creek Dogwood Cornus stolonifera Redosier Dogwood Cornus torreyi Western Dogwood, Creek Dogwood Cornus venus Venus Dogwood Corylus americana American Hazel, American Filbert Corylus avellana Common Filbert Corylus chinensis Chinese Hazel Corylus colurna Turkish Hazel Corylus cornuta var. californica Western Hazel, California Hazel, Western Beaked Hazel Corylus heterophylla Siberian Hazelnut Asian Hazel Cosmos atrosanguineus Chocolate Cosmos Cotinus coggygria Common Smoketree Smokebush Cotinus obovatus American Smoketree, Chittamwood Crataegus ambigua Russian Hawthorn Crataegus autumn Crataegus autumn Crataegus columbiana Columbia Hawthorn Crataegus crus Crataegus crus Crataegus douglasii Black Hawthorn Crataegus germanica Medlar Crataegus laevigata English Hawthorn Crataegus lavallei Lavalle Hawthorn, Carrierei Hawthorn Crataegus monogyna Singleseed Hawthorn, Common Hawthorn, English Hawthorn Crataegus phaenopyrum Washington Hawthorn Crataegus punctata Dotted Hawthorn, Flat-topped Hawthorn Crataegus viridis Green Hawthorn,Southern Hawthorn Daphne cneorum Garland Daphne, Rock Daphne, Rose Daphne Daphne genkwa Lilac Daphne Daphne laureola Spurge Laurel Delphinium Larkspur Eucalyptus cinerea Silver Dollar Eucalyptus, Silver Dollar Gum Argyle Apple Euonymus alatus Euonymus alatus Euonymus americanus American Euonymus, Hearts-a-Burstin', Strawberry Bush Euonymus atropurpureus Eastern Wahoo Euonymus europaeus Common Spindle Tree, European Euonymus Euonymus fortunei Wintercreeper Euonymus, Wintercreeper Euonymus japonicus Japanese Spindle Euonymus kiautschovicus Euonymus kiautschovicus Euphorbia Wood Spurge Fragaria \u00d7 ananassa garden strawberry Fragaria chiloensis Beach Strawberry Sand Strawberry, Chilean Strawberry Galium odoratum Sweet Woodruff Geum Chilean Avens Gleditsia macracantha Large Spined Honeylocust Gleditsia triacanthos Honeylocust Gleditsia triacanthos var. inermis Thornless Honeylocust Helianthus Suncredible Saturn Sunflower Hibiscus syriacus Rose, of Sharon Shrub, Althea Hydrangea anomala var. petiolaris Climbing Hydrangea Hydrangea arborescens Hydrangea, arborescens Hydrangea macrophylla Bigleaf Hydrangea Hydrangea paniculata Panicle Hydrangea Hydrangea quercifolia Oakleaf Hydrangea Kerria japonica Japanese Kerria Japanese Rose Lagerstroemia acoma Acoma Crape Myrtle Lagerstroemia chekiangensis Crape Myrtle Lagerstroemia fauriei Lagerstroemia fauriei Lagerstroemia floribunda Asian Crape Myrtle, Malayan Crape Myrtle, Thai Crape Myrtle Kedah Bungor Lagerstroemia hybrid Hybrid Crape Myrtle Lagerstroemia indica Common Crape Myrtle, Crepe Myrtle Lagerstroemia subcostata var. fauriei Japanese Crape Myrtle Lagerstroemia zuni Zuni Crape Myrtle Leucothoe axillaris Coast Leucothoen Coastal Doghobble Fetter Bush Leucothoe davisiae Western Leucothoe, Sierra Laurel, Mountain Laurel, Black Laurel Leucothoe fontanesiana Drooping Leucothoe, Upland Doghobble Leucothoe grayana Hana-hirinoki (Japan) Leucothoe racemosa Sweetbells Leucothoe, Swamp Doghobble Fetterbush Lonicera ciliosa Western Trumpet Honeysuckle, Orange Honeysuckle Lonicera fragrantissima Winter Honeysuckle, Sweet-Breath-of-Sping January Jasmine Lonicera hispidula Pink Honeysuckle Hairy Honeysuckle, California Honeysuckle Lonicera involucrata Twinberry, Black Twinberry, Inkberry Lonicera japonica Japanese Honeysuckle Lonicera maackii Amur Honeysuckle, Bush, Honeysuckle Lonicera nitida Box Honeysuckle Lonicera pileata Privet, Honeysuckle Lonicera tatarica Tatarian Honeysuckle, Tartarian Honeysuckle Magnolia acuminata Cucumber Magnolia, Cucumbertree Magnolia, Mountain Magnolia Magnolia black Magnolia, black Magnolia butterflies Butterflies Magnolia Magnolia caerhays Magnolia, caerhays Magnolia campbellii Campbell's Magnolia, Campbell Magnolia Pink Tuliptree Magnolia denudata Yulan Magnolia Magnolia elizabeth Elizabeth Magnolia Magnolia ernestii Yellow Lily, Tree Magnolia galaxy Galaxy Magnolia Magnolia grandiflora Southern Magnolia Magnolia insignis Red Lotus Tree Magnolia kobus Kobus Magnolia Magnolia liliiflora Lily, Magnolia Magnolia loebneri Loebner Magnolia Magnolia lotungensis Eastern Joy Lotus Tree Magnolia macrophylla Bigleaf Magnolia Magnolia randy Randy Magnolia Magnolia salicifolia Willowleaf Magnolia, Anise Magnolia Magnolia sargentiana Sargent's Magnolia Magnolia sieboldii Siebold Magnolia, Oyama Magnolia Magnolia soulangiana Saucer Magnolia Magnolia star Magnolia, star Magnolia stellata Star Magnolia Magnolia sunsation Sunsation Magnolia Magnolia tripetala Umbrella Magnolia Umbrella Tree, Elkwood Magnolia virginiana Sweetbay Magnolia Malus 'Adirondack' Adirondack Crabapple Malus 'Coralcole' Coralburst Crabapple Malus 'Donald Wyman' Donald Wyman Crabapple Malus 'Indian Magic' Indian Magic Crabapple Malus atrosanguinea Carmine Crabapple Malus brandywine Brandywine Crabapple Malus floribunda Japanese Flowering Crabapple Malus fusca Pacific Crabapple Malus hupehensis Tea Crabapple Malus prairifire Prairifire Crabapple Malus pumila Apple Malus robusta Cherry, Crabapple Malus sargentii Sargent Crabapple, Pigmy Crabapple Malus snowdrift Snowdrift Crabapple Malus transitoria Transitoria Crabapple Menziesia ciliicalyx var. multiflora Mock Azalea, Menziesia Menziesia ferruginea Rusty Menziesia, Fool's Huckleberry, False Azalea Nandina domestica Heavenly Bamboo Sacred Bamboo, Nandina Parthenocissus quinquefolia Virginia Creeper Woodbine Parthenocissus tricuspidata Boston Ivy, Japanese Creeper Japanese Parthenocissus Photinia ×fraseri Red Tip Photinia Photinia davidiana Chinese Stranvaesia Photinia davidiana var. undulata Wavy-leafed Chinese Stranvaesia Photinia glabra Japanese Photinia Photinia serratifolia Chinese Photinia Taiwanese Photinia Photinia villosa Oriental Photinia Physocarpus capitatus Western Ninebark Pacific Ninebark Physocarpus malvaceus Mallow Ninebark, Mountain Ninebark Physocarpus opulifolius Common Ninebark Platanus acerifolia London Planetree Platanus mexicana Mexican Sycamore Platanus occidentalis American Sycamore, American Planetree Buttonwood Platanus racemosa California Sycamore, Western Sycamore Poa pratensis Kentucky Bluegrass Populus alba White Poplar European White Poplar, Silver Poplar Populus angustifolia Narrowleaf Cottonwood, Mountain Cottonwood Populus balsamifera Balsam Poplar Populus canescens Gray Poplar Populus deltoides Eastern Cottonwood Populus fremontii Fremont Cottonwood, Western Cottonwood Populus grandidentata Bigtooth Aspen Populus nigra Black Poplar Populus tremula European Aspen European Trembling Aspen European Quaking Aspen Populus tremuloides Quaking Aspen Populus trichocarpa Black Cottonwood Prunus americana Wild Plum American (Red) Plum August Plum, Goose Plum Prunus armeniaca Apricot Prunus avium Sweet Cherry Prunus besseyi Sand Cherry, Western Sand Cherry Prunus blireiana Blireiana Plum Prunus caroliniana Carolina Cherrylaurel American Cherrylaurel Prunus cascade Prunus cascade Prunus cerasifera Cherry, Plum Prunus cistena Purpleleaf Sandcherry Redleaf Sandcherry Cistena Sandcherry Cistena Plum Prunus dream Prunus dream Prunus emarginata Bitter Cherry, Wild Cherry, Quinine Cherry Prunus first Prunus first Prunus fruticosa Steppe Cherry, European Dwarf Ground Cherry, Mongolian Cherry Prunus glandulosa Dwarf Flowering Almond Prunus ilicifolia Hollyleaf Cherry, Holly-leaved Cherry Prunus laurocerasus Cherry, Laurel Prunus lusitanica Portugal Laurel Prunus maackii Amur Chokecherry Amur Cherry, Manchurian Cherry Prunus mume Japanese Apricotc Japanese Flowering Apricot Japanese Flowering Plum Prunus newport Newport Flowering Plum Prunus okame Okame Flowering Cherry Prunus padus European Birdcherry Common Birdcherry Prunus prostrata Rock Cherry, Mountain Cherry Prunus sargentii Sargent Cherry, Sargent's Cherry Prunus serotina Black Cherry, Rum Cherry Prunus serrula Birchbark Cherry, Paperbark Cherry, Tibetan Cherry Prunus serrulata Japanese Flowering Cherry Prunus snow Prunus snow Prunus subcordata Klamath Plum, Sierra Plum, Pacific Plum Prunus subhirtella Higan Cherry Prunus subhirtella var. autumnalis Autumn Flowering Higan Cherry Prunus tai Prunus tai Prunus virginiana Prunus virginiana Prunus virginiana var. demissa Western Chokecherry Prunus virginiana var. virginiana Common Chokecherry, Eastern Chokecherry Prunus yedoensis Yoshino Cherry, Somei-yoshino Cherry, Tokyo Cherry Pyrus calleryana Callery Pear Pyrus communis Common Pear Pyrus fauriei Pyrus fauriei Pyrus salicifolia Pyrus salicifolia Quercus acutissima Sawtooth Oak Quercus agrifolia Coast Live Oak Quercus alba (Eastern) White Oak Quercus arizonica Arizona Oak, Arizona White Oak Quercus berberidifolia California Scrub Oak, Scrub Oak, Inland Scrub Oak Quercus bicolor Swamp White Oak Quercus bimundorum Two Worlds Oak, Bimundors Oak Quercus castaneifolia Chestnut-leaved Oak, Chestnutleaf Oak, Persian Oak Quercus cerris Turkey Oak Quercus chrysolepis Canyon Live Oak Quercus coccinea Scarlet Oak Quercus douglasii Blue Oak, California Blue Oak Quercus durata Leather Oak Quercus emoryi Emory Oak, Black Oak, Blackjack Oak Quercus engelmannii Engelmann Oak, Mesa Oak Quercus frainetto Hungarian Oak, Italian Oak Quercus gambelii Gambel Oak, Rocky Mountain White Oak Quercus garryana Oregon White Oak Quercus garryana var. breweri Brewer's Oak Quercus glandulifera Konara Oak Quercus glauca Japanese Blue Oak, Ring-cupped Oak Quercus hypoleucoides Silverleaf Oak, Whiteleaf Oak Quercus ilex Holly, Oak, Holm Oak Quercus ilicifolia Bear Oak Quercus imbricaria Shingle Oak Quercus kelloggii California Black Oak Quercus leana Lea's Oak Quercus lobata Valley Oak, Roble Oak, California White Oak Quercus macrocarpa Bur Oak, Mossycup Oak Quercus marilandica Blackjack Oak, Jack Oak Quercus mongolica Mongolian Oak Quercus montana Mountain Chestnut, Oak, Chestnut, Oak, Rock Chestnust Oak Quercus muehlenbergii Chinkapin Oak, Chinquapin Oak, Yellow Chestnut, Oak Quercus myrsinifolia Chinese Evergreen Oak, Bamboo-leaf Oak Quercus nigra Water Oak, Possum Oak Quercus palustris Pin Oak, Swamp Spanish Oak Quercus petraea Sessile Oak, Durmast Oak, Irish Oak Quercus phellos Willow, Oak Quercus prinoides Dwarf Chinquapin Oak, Dwarf Chestnut, Oak, Scrub Chestnut, Oak Quercus robur English Oak Quercus rubra Northern Red Oak Quercus sadleriana Sadler Oak, Deer Oak Quercus stellata Post Oak Quercus suber Cork Oak Quercus turbinella Scrub Live Oak Quercus undulata Wavyleaved Oak Quercus vaccinifolia Huckleberry, Oak Quercus velutina Black Oak Quercus virginiana Southern Live Oak, Live Oak Quercus wislizeni Interior Live Oak, Chapparal Oak Rhamnus alnifolia Alder Buckthorn, Glossy Buckthorn, Breaking Buckthorn Rhododendron 'Purple Gem' Purple Gem Rhododendron Rhododendron airy Rhododendron, airy Rhododendron alabamense Alabama Azalea Rhododendron alice Alice Rhododendron Rhododendron anah Rhododendron, anah Rhododendron anna Rhododendron, anna Rhododendron april Rhododendron, april Rhododendron arboreum subsp. cinnamomeum Cinnamon Rhododendron Rhododendron argosy Argosy Rhododendron Rhododendron augustinii Augustine Rhododendron Rhododendron auriculatum No common name (R. auriculatum) Rhododendron beauty Rhododendron, beauty Rhododendron bibiani Bibiani Rhododendron Rhododendron blue Rhododendron, blue Rhododendron boule Rhododendron, boule Rhododendron bow Rhododendron, bow Rhododendron bric Rhododendron, bric Rhododendron bureavii Bureau Rhododendron Rhododendron campylocarpum subsp. coloxanthum Coloxanthum Rhododendron Rhododendron catawbiense Catawba Rhododendron Rhododendron cheer Cheer Rhododendron Rhododendron chevalier Rhododendron, chevalier Rhododendron christmas Rhododendron, christmas Rhododendron cinnabarinum Cinnabar Rhododendron Rhododendron concinnum Concinnum Rhododendron Rhododendron cotton Rhododendron, cotton Rhododendron crater Rhododendron, crater Rhododendron crest Crest Rhododendron Rhododendron cunninghams Rhododendron, cunninghams Rhododendron cynthia Cynthia Rhododendron Rhododendron daphnoides Daphnoides Rhododendron Rhododendron dauricum Dauricum Rhododendron Rhododendron davidsonianum Davidsonianum Rhododendron Rhododendron day Rhododendron, day Rhododendron deciduous Rhododendron, deciduous Rhododendron defines Rhododendron, defines Rhododendron delaware Rhododendron, delaware Rhododendron dora Rhododendron, dora Rhododendron dreamland Dreamland Rhrododendron Rhododendron el Rhododendron, el Rhododendron elisabeth Rhododendron, elisabeth Rhododendron elizabeth Elizabeth Rhododendron Rhododendron falconeri subsp. falconeri Falconer Rhododendron Rhododendron fantastic Fantastic Rhododendron Rhododendron formosum var. formosum Formosum Rhododendron Rhododendron forrestii subsp. forrestii Forrest Rhododendron Rhododendron fortunei subsp. discolor Fortune Discolor, Discolor Rhododendron Rhododendron frilly Rhododendron, frilly Rhododendron gartendirektor Rhododendron, gartendirektor Rhododendron girards Rhododendron, girards Rhododendron goldflimmer Goldflimmer Rhododendron Rhododendron grace Rhododendron, grace Rhododendron groenlandicum Labrador-tea, Labrador Tea Rhododendron haematodes subsp. haematodes Haematodes Rhododendron Rhododendron hallelujha Hallelujah Rhododendron Rhododendron hanceanum Hanceanum Rhododendron Rhododendron hardijzer Rhododendron, hardijzer Rhododendron harry Rhododendron, harry Rhododendron hino Rhododendron, hino Rhododendron hinode Rhododendron, hinode Rhododendron hippophaeoides var. hippophaeoides Hippophaeoides Rhododendron Rhododendron hodgsonii Hodgson Rhododendron Rhododendron honourable Rhododendron, honourable Rhododendron horizon Rhododendron, horizon Rhododendron hotei Hotei Rhododendron Rhododendron irroratum Irroratum Rhododendron Rhododendron jock Jock Rhododendron Rhododendron johnstoneanum Rhododendron, johnstoneanum Rhododendron kaempferi Torch Azalea Rhododendron keiskei Keiskei Rhododendron, Keisuki Rhododendron Rhododendron ken Rhododendron, ken Rhododendron kiusianum Kiusianum Azalea, Kyushu Azalea Rhododendron lacteum Lacteum Rhododendron Rhododendron lees Rhododendron, lees Rhododendron lems Rhododendron, lems Rhododendron lights Rhododendron, lights Rhododendron loderi Rhododendron, loderi Rhododendron luteiflorum Luteiflorum Rhododendron Rhododendron lutescens Lutescens Rhododendron Rhododendron luteum Pontic or Pontica Azalea Rhododendron macabeanum Macabeanum Rhododendron Rhododendron macrophyllum Pacific Rhododendron Rhododendron moonstone Moonstone Rhododendron Rhododendron mrs Rhododendron, mrs Rhododendron mucronulatum Rhododendron, mucronulatum Rhododendron myrtifolium Myrtifolium Rhododendron Rhododendron niveum Niveum Rhododendron Rhododendron northern Rhododendron, northern Rhododendron occidentale Western Azalea Rhododendron orbiculare subsp. orbiculare Obiculare Rhododendron Rhododendron orchid Rhododendron, orchid Rhododendron oreotrephes Oreotrephes Rhododendron Rhododendron oudijks Rhododendron, oudijks Rhododendron pachytrichum Pachytrichum Rhododendron Rhododendron peekaboo Peekaboo Rhododendron Rhododendron pink Rhododendron, pink Rhododendron pioneer Rhododendron, pioneer Rhododendron pjm P.J.M. Rhododendron Rhododendron point Rhododendron, point Rhododendron ponticum Rhododendron, ponticum Rhododendron president Rhododendron, president Rhododendron prinophyllum Roseshell Azalea, Pinkshell Azalea Rhododendron prunifolium Plumleaf Azalea Rhododendron quinquefolium Quinquefolium Azalea Rhododendron racemosum Racemosum Rhododendron Rhododendron ramapo Ramapo Rhododendron Rhododendron rosamundi Rosamundi Rhododendron Rhododendron roseum Rhododendron, roseum Rhododendron rosy Rhododendron, rosy Rhododendron roxieanum var. oreonasters No common name Rhododendron rubiginosum Rubiginosum Rhododendron Rhododendron sappho Sappho Rhododendron Rhododendron scarlet Rhododendron, scarlet Rhododendron schlippenbachii Royal Azalea Rhododendron serpyllifolium Wild Thyme, Azalea Rhododendron serpyllifolium var. albifolrum White Wild Thyme, Azalea Rhododendron sinofalconeri Sinofalconer Rhododendron Rhododendron sinogrande Sinogrande Rhododendron Rhododendron smirnowii Smirnow Rhododendron Rhododendron snow Rhododendron, snow Rhododendron stenopetalum Rhododendron, stenopetalum Rhododendron taurus Taurus Rhododendron Rhododendron temple Rhododendron, temple Rhododendron thomsonii subsp. thomsonii Thomson Rhododendron Rhododendron tri Rhododendron, tri Rhododendron trilby Trilby Rhododendron Rhododendron unique Unique Rhododendron Rhododendron vulcan Vulcan Rhododendron Rhododendron wardii Ward Rhododendron Rhododendron white Rhododendron, white Rhododendron wiltonii Wilton Rhododendron Rhododendron winsome Winsome Rhododendron Rhododendron yakushimanum Yak Rhododendron Ribes aureum Golden Currant, Buffalo Currant Ribes cereum Wax Currant Ribes davidii ge ye cha biao zi (革叶茶藨子) (Chinese name) Ribes divaricatum Coast Black Gooseberry, Straggly Gooseberry Ribes gordonianum Gordon's Currant Ribes malvaceum Chaparral Currant Ribes nevadense Mountain Pink Currant, Pink Sierra Currant, Sierra Currant Ribes odoratum Golden Currant, Missouri Currant, Clove Currant, Buffalo Currant Ribes roezlii Sierra Gooseberry, Roezl's Gooseberry, Mountain Gooseberry Ribes sanguineum Red-flowering Currant Rosa acicularis Wild Prickly Rose Rosa gymnocarpa Little Wood Rose, Wood Rose, Baldhip Rose Rosa multiflora Multiflora Rose Rosa nutkana Nootka Rose Rosa pisocarpa Clustered Rose, Swap Rose Rosa rubiginosa Sweetbriar Rose, Eglantine Rose Rosa rugosa Rugosa Rose, Beach Tomato, Sea Tomato Rosa woodsii Woods' Rose Rubus allegheniensis Allegheny Blackberry Rubus armeniacus Himalayan Blackberry Armenian Blackberry Rubus calycinoides Crinkle-leaf Creeper Creeping Raspberry Yü-shan raspberry Rubus dicolor Himalayan Blackberry Armenian Blackberry Rubus hayata Rubus hayata Rubus laciniatus Evergreen Blackberry Cutleaf Blackberry Rubus leucodermis Blackcap, Western Raspberry Rubus lineatus Silky-leaved Berry Rubus odoratus Flowering Raspberry Purple-flowering Raspberry Rubus parviflorus Thimbleberry Western Thimbleberry Rubus rolfei Creeping Raspberry, Crinkle-leaf Creeper Rubus spectabilis Salmonberry Rubus tricolor Creeping Bramble Korean Raspberry Rubus ursinus Trailing Blackberry Western Blackberry California Blackberry Dewberry Sedum Stonecrop Solanum aviculare Kangaroo Apple Spiraea betulifolia Birch-leaf Spirea, Shiny-leaf Spirea, White Spirea Spiraea densiflora Rose, Meadowsweet, Mountain Spirea, Subalpine Spirea Spiraea double Spiraea, double Spiraea douglasii Rose, Spirea Spiraea fritschiana Korean Spirea Spiraea japonica Japanese Spirea Spiraea japonica var. alpina Daphne, Spirea Spiraea miyabei Miyabe Spirea Spiraea nipponica Nippon Spirea Spiraea prunifolia Spiraea, prunifolia Spiraea splendens Mountain Spirea, Rose Meadowsweet, Subalpine Spirea Spiraea thunbergii Thunberg Spirea Spiraea vanhouttei Van Houtte Spirea, Bridal Wreath Spirea Stachys Bella Grigio Stachys Symphoricarpos albus Common Snowberry Symphoricarpos doorenbosii Doorenbos Snowberry, Doorenbos Coralberry Symphoricarpos mollis Spreading Snowberry, Creeping Snowberry, Mountain Snowberry Symphoricarpos orbiculatus Indiancurrant Coralberry Buckbrush Symphoricarpos rotondifolius Roundleaf Snowberry, Huckleberry-flowered Snowberry Symphytum Axminster Gold Variegated Russian Comfrey Syringa chinensis Chinese Lilac Rouen Lilac Syringa hyacinthiflora Early Flowering Lilac, Early Hybrid Lilac Syringa josikaea Hungarian Lilac Syringa laciniata Cutleaf Lilac Syringa meyeri Syringa meyeri Syringa microphylla Syringa microphylla Syringa patula Syringa patula Syringa pekinensis Peking Lilac Chinese Tree, Lilac Syringa prestoniae Preston Lilac, Canadian Lilac Syringa reticulata Japanese Tree Lilac, Giant Tree Lilac Syringa vulgaris Common Lilac Tolmiea menziesii Piggyback Plant Trifolium tridentatum Tomcat Clover Verbena Purple Vervain Veronica American Brooklime or American Speedwell Viburnum awabuki Sweet Viburnum Viburnum bodnantense Viburnum, bodnantense Viburnum bracteatum Bracted Viburnum, Limerock Arrowwood Viburnum Viburnum burkwoodii Burkwood Viburnum Viburnum carlesii Koreanspice Viburnum Viburnum cassinoides Witherod Viburnum, Northern Wild Raisin Viburnum cinnamomifolium Cinnamon Viburnum Viburnum davidii David's Viburnum Viburnum dentatum Arrowwood Viburnum Viburnum dilatatum Linden, Viburnum, Linden, Arrowwood Viburnum edule Mooseberry Highbush Cranberry, Moosewood Viburnum, Squashberry Viburnum ellipticum Oregon Viburnum, Western Wayfaring Tree Viburnum farreri Fragrant Viburnum Viburnum juddii Judd Viburnum Viburnum lantana Wayfaringtree Viburnum Viburnum lantanoides Hobblebush Viburnum lentago Nannyberry Sheepberry Viburnum nudum Possumhaw Smooth Witherod Northern Wild Raisin Viburnum opulus var. americanum American Cranberrybush Viburnum Viburnum opulus var. opulus European Cranberrybush Viburnum, Guelder-rose Viburnum opulus var. sargentii Sargent Viburnum Viburnum plicatum var. plicatum Japanese Snowball Viburnum Viburnum plicatum var. tomentosum Doublefile Viburnum Viburnum pragense Prague Viburnum Viburnum prunifolium Blackhaw Viburnum Viburnum rafinesquianum Downy Arrowwood Viburnum, Rafinesque Viburnum Viburnum rhytidophyllum Leatherleaf Viburnum Viburnum rufidulum Rusty Blackhaw Viburnum, Southern Blackhaw Viburnum setigerum Tea Viburnum Viburnum suspensum Sandankwa Viburnum, Sandanqua Viburnum Viburnum tinus Laurustinus Viburnum trilobum American Cranberrybush Viburnum Vinca major Large Periwinkle Viola Hookedspur Violet Vitis californica Vitis californica Vitis coignetiae Crimson Glory Vine Vitis vinifera European grape