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Garden WiseNon-Invasive Plants for Your GardenWestern Washington Guide
Voluntary codes of conductFor the gardening public (annotated):In an effort to reduce the spread of invasive plants used forhorticultural purposes, experts have created the “VoluntaryCodes of Conduct,” a series of steps that nursery professionals,landscape architects, gardeners, and others can take to help curbthe spread of invasive horticultural plants. Ask for only non-invasive species when you acquire plants.Plant only environmentally safe species in your gardens.Work towards and promote new landscape design that isfriendly to regional ecosystems. Seek information on which species are invasive in your area.Sources could include botanical gardens, horticulturists,conservationists, and government agencies. Remove invasivespecies from your land and replace them with non-invasivespecies suited to your site and needs. Do not trade plants with other gardeners if you know theyare species with invasive characteristics. Request that botanical gardens and nurseries promote,display, and sell only non-invasive species. Help educate your community and other gardeners in yourarea through personal contact and in such settings as gardenclubs and other civic groups.For the full Gardening Codes of Conduct, or to learn aboutthe Codes of Conduct for Government, Nursery Professionals,Landscape Architects, and Botanic Gardens and Arboreta, pleasego to the Invasive.org, TNC’s Global Invasive Species Teamwebpage: l.Garden Wise is dedicated toAnn Lennartz
Garden WiseNon-Invasive Plants for Your GardenWhile most exotic plants are not problematic, a few have becomeinvasive in Washington State. When these plants spread towild areas, they cause serious problems. For example invasiveknotweeds, butterfly bush, and yellow flag iris are changing ourstreamsides and riverbanks; spurge laurel and Atlantic ivy arealtering our forests.This booklet represents the collaboration of nonprofitconservation groups, state and country government, and thenursery industry. We believe that preventing introduction is themost efficient way to reduce the spread and impact of invasivespecies. Whether you are looking for new and exciting plants toadd to your garden, or you are looking to replace invasive plantsin your yard, we hope this book will be a valuable resource.Working together, we can ensure that future generations enjoypristine wild areas in Washington State.Please note that this booklet is a product of an ongoing project.Visit www.nwcb.wa.gov for updates and to learn about otherproblematic plants and their alternatives. You can also learnmore from your local nursery, WSU Master Gardeners, and atwww.GreatPlantPicks.org.Full SunRegular WaterWell-DrainedSoilPart SunMedium WaterHeavy SoilFull ShadeLow duousGreat PlantPick
HerbaceousCommon Fennel - Foeniculum vulgareeivsvanINon-bulbing varieties ofRecommended Alternative 2 this herb are prized for theirtall, feathery, aromatic, andoften colorful foliage. However, thisperennial colonizes grasslands anddisturbed areas, including roadsidesand abandoned lots, where densestands can crowd out native flora.Fennel escapees are a seriousproblem in California, particularlyin natural, open lands and alongthe coast. Fennel invasions arebecoming a common sight inwestern Washington and may posean additional threat to our state’svanishing grasslands.Class B Washington State Noxious WeedFlorence Fennel, Finocchio, Bulbing FennelFoeniculum vulgare var. azoricumThis annual plant is most likecommon fennel, with the samefeathery foliage and is ideal forculinary uses. The flavor of foliage and seeds isvery similar to common fennel,and the swollen stem base isa crispy, flavorful vegetable usedin many cuisines. The foliage is green and has afeathery texture like commonfennel, but the plant is smaller instature (2-3 feet, not 4-6 feet). Like common fennel, Florencefennel likes full sun and welldrained soils. The yellow flowers attractbutterflies, and butterfly larvaefeed on the foliage. USDA zones 4-9
Recommended AlternativeDillAnethum graveolensThe foliage of this plant is alsofeathery and reaches 3-4 feet. With a wonderful featheryfoliage, dill offers a fennel-likehazy texture, although the plantis slightly smaller in stature. Dill is easy to grow in sunny, welldrained sites. This annual will self-sow in yourgarden, so remove spent flowerheads before seeds scatter. Flat yellow flowers appearabout the same time as thoseof fennel, attracting butterflies,and butterfly larvae feed on thefoliage. USDA zones 3-7Recommended AlternativeCosmosCosmos bipinnatusCosmos foliage is ferny likecommon fennel, but its daisy-likeflowers differ. This annual has a long bloomtime, from summer into autumn. It can add pink, purple or whitecolor to the garden. The profuse, 3-inch daisy-likeflowers, create a different effect inthe garden than fennel. Easy to grow and care for, cosmoscan be deadheaded to prolongflowering. Cosmos prefers well-drainedsoils and needs sunny sites, likecommon fennel. USDA zones 3-10Image courtesy of Trois HelvyMore choices: Amelanchier alnifolia, Cornus stolonifera (syn. Cornus sericea),Holodiscus discolor, Hydrangea macrophylla, Physocarpus capitatus, Woodwardiafimbriata, and Calamagrostis x acutiflora ‘Karl Foerster’ all of which areWashington natives except for Hydrangea and Calamagrostis. 3 Courtesy of Deborah Jordan, Solas Gardens
HerbaceousItalian Arum - Arum italicumeivsvanIIntroduced to gardens for itsbright orange berries and variegatedleaves that form a groundcover,Italian arum is agarden escapeethat is invadingnatural areasin Washington.While new plantscan grow from theberries dispersedby birds, plant infestations rapidly multiplyby their underground tubers. These tubers areeasily spread to new locations in contaminatedsoil. This toxic plant is extremely difficult tocontrol once established and new populationsBottom image courtesy of Timare continually discovered.Recommended Alternative 4 Miller, WSU-NWRECClass C Washington State Noxious WeedDull Oregon GrapeMahonia nervosa (syn. Berberis nervosa)This beautiful, evergreen lowgrowing shrub is native toWashington. Plants spread by rhizomes to forma loose groundcover. Leaves are compound, made upof dark green, leathery leaflets,having toothed margins and asomewhat dull surface. Slender clusters of bright yellowflowers bloom in the spring andform deep blue, waxy berries. Able to grow in part sun andshade, dull Oregon grape isdrought tolerant once established. USDA zones 5-9Image courtesy of Great Plant Picks
Recommended AlternativeWhite Fawn LilyErythronium oregonumThis native fawn lily producesbeautiful white flowers andmottled leaves. This perennial grows from a corm,typically producing a pair oflance-shaped leaves at the base ofthe flower stem. Like Italian arum, white fawn lilyhas interesting coloring on itsleaves. One to three nodding, whiteflowers bloom on stems that areup to 12 inches tall. Ideal for woodland gardens, it cangrow in full sun to part shade andprefers well-draining soil. USDA zones 7-9Recommended AlternativeInside-out FlowerVancouveria hexandraThis native perennial forms a lovelygroundcover of light green leaves. The compound leaves are madeof lobed leaflets that emerge inspring. Small, white delicate flowersbloom in the spring, appearing asif they’ve been turned inside-out.Each stem forms 10 to 30 flowers Plants grow from rhizomes inmoist to somewhat dry soils. Itis fairly drought-tolerant onceestablished. USDA zones 5-9Image courtesy of Walter Siegmund, CC BY-SA3.0, commons.wikimedia.orgMore choices: Kinnikinnick, (Arctostaphylos uva-ursi) and Beesia (Beesiadeltophylla). 5 Courtesy of Richie Steffen, Great Plant Picks
HerbaceousPoliceman’s Helmet - Impatiens glanduliferaeivsvanIPoliceman’s helmet has pretty pink-to-purple flowers andRecommended Alternative 6 is unusually tall for an annual plant, reaching amaximum height of 10 feet. A garden escapee, thisprolific, self-seeding plant has heavily colonizedlowland riparianareas, includingforests, streambanks, androadsidethickets,where it dominates nativeplant communities. Althoughconsidered a serious problem inGreat Britain, and on the WSDAquarantine list, it is still oftenillegally exchanged amongstImage courtesy of King County NWCBgarden groups in Washington.Class B Washington State Noxious WeedMilky BellflowerCampanula lactiflora ‘Loddon Anna’An upright long-bloomingperennial for a well-drained, sunnyto partly shady site. This easy-to-grow perennial willlast in your garden to add colorand texture over many years. The upright habit, reaching up to4 to 5 feet, adds similar textureand height to the garden. Beautiful light lilac-pink starshaped flowers in panicles aresimilar in color, but not form, topoliceman’s helmet. Blooms mid-summer, trim backfading flowers to encourge rebloom later in the season. USDA zones 5-8Image courtesy of Ann Chapman
Recommended AlternativeDelphinium, LarkspurDelphinium parishii ‘Sky blue’and Delphinium x elatumAn upright, taller herbaceousperennial for a sunny site. The flower color ranges fromwhite to deep lavenders and blues. Some cultivars reach heightssimilar to policeman’s helmet. Spurred flowers on long spikesattract butterflies. This deciduous perennial growsback stronger each year. Checkwith your local nursery fordisease-resistant cultivars. USDA zones 4-7Recommended AlternativeCardinal FlowerLobelia cardinalis & cultivarsAn upright herbaceous perennialfor a moist, sunny to partly shadysite. Cardinal flower grows in similarconditions as policeman’s helmet:moist soils and part shade. Showy flower spikes can reachheights of 3 feet, shorter thanpoliceman’s helmet. Blooms are generally brightcrimson, though color can rangefrom orange-red to fuschia topurple in some cultivars. A popular choice for attractinghummingbirds. USDA zones 3-10Image courtesy of Erv Evans,North Carolina State UniversityMore choices: Cleome species, flowering tobacco (Nicotiana mutabilis), Japanese primrose(Primula japonica), Thalictrum delavayi ‘Hewitt’s Double’, and natives: western meadow-rue(Thalictrum occidentale), bleeding heart (Dicentra formosa), western blue flax (Linum perenne),monkeyflowers (Mimulus guttatus and M. lewisii), and inside-out flower (Vancouveria hexandra). 7 Image courtesy of Monrovia Nursery
HerbaceousevsiavInTall or Purple Verbena - Verbena bonariensisTall verbena has been a popular addition to gardenborders for its lavender, tubular flower clusters borneatop elevated flower stalks. Although attractive inthe garden, thisvigorously selfseeding perennial israpidly spreading intofields and open areasaround the world,including the state ofOregon, and is on its way to beinga problem in western Washington.The prickly hairs on the stem makethis weed difficult to hand pull.Identify it early and nip it in thebud!Recommended Alternative 8 Image courtesy of John Randall,The Nature ConservancyWashington State Monitor SpeciesNative Penstemon speciesPenstemon speciesThere are many beautiful, nativepenstemon species that can growin your garden. Penstemons are typically shortlived perennials that producebeautiful clusters of flowers, ofcolors including pink, violet, andwhite. Penstemons have opposite leavesand five-petaled flowers, whichare fused and form a tube withtwo ‘lips’ at the top. These species will attractpollinators to your garden. Check your growing conditions tomake sure you plant in the rightplace. USDA zones vary, many 5-9Image of coast penstemon (Penstemonserrulatus) courtesy of Ben Leger
Recommended AlternativeFrikart’s AsterAster frikartii ‘Mönch’This prolific bloomer grows in amounded form in full sun. The long flowering period (JulyOctober) offers lavender-blueflowers throughout the season. A more densely branched habitthan tall verbena, Frikart’s astergrows 1.5 to 3 feet tall, prefersfull sun but can grow in partshade. Provides color in the landscapewhen other plants are dying backin autumn. Its 2.5 inch flowers attractpollinators such as butterflies. USDA zones 5-8Recommended AlternativePincushion FlowerScabiosa caucasica ‘Ultra Violet’An ever-blooming perennial for awell-drained, sunny site. This cultivar’s bright violetpincushion-shaped flowers areperched on thin stems to 2 feettall Pincushion flower is not onlygreat for cutting, but it alsoattracts butterflies in the garden. ‘Ultra Violet’ is a new cultivarwith greater disease resistancethan past offerings. USDA zones 4-9Image courtesy of Kennedy HarrisMore choices: Homestead purple verbena (Verbena ‘Homestead Purple’) and nativecamas (Camassia quamash). 9 Image courtesy of Bellevue Botanical GardenSociety, Great Plant Picks
HerbaceousKnotweeds - Polygonum & Persicaria specieseivsGiant, Bohemian, Japanese, & HimalayanvanIFeathery white flower heads, largeRecommended Alternative 10 foliage, and tall, bamboo-like stems oncemade this group of knotweeds popular asgarden ornamentals. Native to Asia, knotweedshave become a serious problem worldwideand areincreasinglyprevalent inWashington. They rapidly invaderiparian zones: blocking sunlight,disturbing nutrient cycling, andfacilitating stream bank erosion.These knotweeds are a seriousproblem along Washington Statewaterways where they degradehabitat for wildlife and fish speciesincluding salmon.Image courtesy of Whatcom County NWCBClass B Washington state noxious weed’sGoat’s BeardAruncus dioicusThis robust perennial nativeprovides height to your garden. Like knotweed, goat’s beardthrives in moist soil. It produces a panicle of creamcolored flowers similar toknotweeds, though foliagetexture is finer. Blooms in June and July, a littleearlier than knotweeds. Goat’s beard grows up to 6 feettall. USDA zones 3-7Image courtesy of Erv Evans,North Carolina State University
Fothergilla majorThis is a deciduous shrub withgorgeous fall foliage. Small, fragrant white flowersbloom in spring, unlike the laterblooming knotweeds. Green foliage in summer turns tospectacular fall color, as opposedto less colorful knotweeds. Like knotweeds, fothergilla sportslarge leaves up to 5 inches long. Shrub grows up to 9 feet tall. Cultivar ‘Mt. Airy’ grows 5 to 6feet tall and is a Great Plant Pick. Also known as witch-alder, thisshrub prefers moist, well-drainedsoils. USDA zones 4-8Image courtesy of Victor CarranoFalse Solomon’s SealMaianthemum racemosum(syn. Smilacina racemosa)This plant is a shade-loving, earlyblooming native perennial withgracefully arching stems. Clusters of delicate, creamy whiteflowers appear in mid-spring,before knotweed blooms. The flowers are lightly fragrant. Lance-shaped leaves reach lengthsof 8 inches. It grows to around 3 feet in heightand spreads to create a large patchin the right place. It prefers partial shade and adaptswell to a variety of soils. USDA Zones 4-9.Image courtesy of Pat Breen,Oregon State UniversityMore choices: Western serviceberry (Amelanchier alnifolia), ocean-spray (Holodiscus discolor),giant chain fern (Woodwardia fimbriata), red osier dogwood (Cornus sericea), all of whichare Washington natives, as well as bigleaf hydrangea (Hydrangea macrophylla) and giantfleeceflower (Persicaria polymorpha). 11 Recommended AlternativeRecommended AlternativeFothergilla
GroundcoverYellow Archangel - Lamiastrum galeobdoloneivsvaStriking variegated leavesnIand the ability to thriveRecommended Alternative 12 in shady areas makes yellowarchangel a popular ornamentalplant for groundcoverand hanging baskets.Unfortunately,this trailing planteasily establisheswild populations, inmany cases as theresult of improperdisposal of gardencuttings or hangingbaskets. Yellow archangel forms dense,homogenous mats in forests and parksand is a serious problem in BritishColumbia and western Washington.Class B Washington State Noxious WeedWintercreeperEuonymus fortunei ‘SilverQueen’& ‘Emerald Gaiety’This is a low-growing evergreenplant with attractive foliage. The variegated leaves ofwintercreeper provide contrast inthe low light preferred by yellowarchangel. Wintercreeper will tolerate fullsun as well as the shade thatyellow archangel prefers. USDA zones 4-8Image courtesy of Monrovia Nursery
Recommended AlternativeHeucheras & HeucherellasHeuchera & Heucherella speciesLow-growing perennials, somenative to the Northwest. These plants produce small, airyflowers above ornamental leavesin a variety of colors and patterns,rivaling the foliage of yellowarchangel. Heucheras and heucherellastolerate sun to light shade. Their delicate flowers are alsoattractive to hummingbirds. USDA zones 4-9Recommended AlternativeWild GingerAsarum caudatumEvergreen groundcover growing inpart to full shade. Beautiful deep green, heartshaped leaves smell of lemonginger when crushed. Unique purple-brown flowers thatmay be covered by leaves, unlikethe insignificant flowers of yellowarchangel. Grows in a variety of gardenconditions and is drought tolerantonce established. Grows by rhizomes and slowlyforms expanding mats. USDA zones 7-9Image courtesy of Richie Steffen, Great Plant PicksMore choices: Bleeding heart (Dicentra formosa), wild lily-of-the-valley (Maianthemumdilatatum), three-leaf foamflower (Tiarella trifoliata), all of which are Washington natives, aswell as barrenwort (Epimedium) species, sweetbox (Sarcococca hookeriana var. humilis), andminature London pride (Saxifraga ‘Primuloides’). 13 Top Heuchera Image : Victor CarranoBottom Heuchera Image: Terra Nova Nurseries
GroundcovereOld Man’s Beard & Silverlace VineivClematis vitalba & Polygonum aubertii (Fallopia baldschuanica)svanIClimbing vines such asRecommended Alternative 14 old man’s beard and silverlacevine are commonly used onarbors and trellises. Yet these vinescan establish in forests and alongriverbanks where they can smothershrubs and trees and form densemats in the understory, displacingnative flora. Both vines producethousands of tiny seeds, whichare spread by wind or carried onthe bodies of birds. Silverlace vinecan also regenerate from gardencuttings tossed aside, makingescape from cultivation easy.Images courtesy of King County NWCB.Class C Washington State Noxious Weed & Monitor SpeciesSweet Autumn ClematisClematis paniculata,synonym C. dioscoreifoliaThis clematis is a vigorous andfragrant climber. This clematis has fragrant creamywhite flowers. Like the invasive vines, this is arobust climber. It takes full sun to partial shade. Like silver lace vine and old man’sbeard, Sweet Autumn clematisblooms from summer to fall. This climber grows up to 20 feettall. USDA zones 5-9Image courtesy of Monrovia Nursery
Recommended AlternativeItalian ClematisClematis viticella & cultivarsThis species includes a variety ofcolorful cultivars. There are various flower colors tochoose from, whereas the invasivevines offer only white. Growing only 15 feet tall, it doesnot overburden trees like theinvasive vines. This clematis prefers full sun. Like silverlace vine and old man’sbeard, this plant is not particularabout soil type. Zones 5-9Recommended AlternativeOrange HoneysuckleLonicera ciliosaOrange honeysuckle is a colorfulnorthwest native that butterfliesand birds love too. The flowers are a brilliant orangeinstead of white. It grows up to 30 feet tall, like oldman’s beard. This native takes full sun topartial shade. Blooms occur from May to July,earlier than either of the invasivevines. Birds and butterflies are attractedto its edible berries and nectarflowers. Zones 4-9Image courtesy of Ben LeglerMore choices: Kiwi vine (Actinidia kolomikta), Japanese hydrangea vine (Schizophragmahydrangeoides), climbing hydrangea (Hydrangea anomala subsp. petiolaris), andsilvervein creeper (Parthenocissus henryana). 15 Image courtesy of Pat Breen, Oregon State Univ.
GroundcovereRecommended Alternative 16 vsiavInAtlantic & Invasive English Ivy CultivarsHedera hibernica & Hedera helix ‘Baltica’,‘California’, ‘Pittsburgh’, & ‘Star’While over 400 cultivars ofivy are used for landscaping,only a few are considered invasive.When allowed to climb and mature,invasive ivies produce seed-filledberries which are spread by birds.A serious problem in westernWashington, these cultivars spreadinto forests where the vines blocksunlight, smother trees, andencourage rot. Dense mats of ivyblanket the forest understory,displace native flora, outcompeteforest seedlings, and harbor pestssuch as rats.Class C Washington State noxious weedCrinkle-Leaf CreeperRubus pentalobus(syn. Rubus calycinoides)Forms a great, durable carpetof rough leaves, dark green insummer and tinged reddish inwinter. This creeper is a goodgroundcover for slopes and willgrow to cover larger spaces. It is drought tolerant like ivy,once established. Crinkle-leaf creeper is anattractive evergreen, finer intexture than ivy—with leaves thesize of strawberry leaves. It grows well in sun and partialshade and remains healthy withlittle care. USDA zones 6-9Image courtesy of Pat Breen, Oregon State Univ.
Recommended AlternativeKinnikinnickArctostaphylos uva-ursiA great native plant for carpetingthe ground, Kinnikinnick helpssustain wildlife. Its evergreen foliage and mat-likespreading habit give an emeraldlook year-round. Like ivy, kinnikinnick is adaptedto well-drained sandy soils andsun. Though drought tolerant onceestablished, unlike ivy, it doesnot tolerate shade. Unlike ivy, kinnikinnick flowersare ornamental. Whitish-pinkbells appear in summer, followedby red berries. USDA zones 5-10Recommended AlternativeClimbing Hydrangea 17 Image courtesy of Ben LeglerHydrangea anomala subsp.petiolarisA good vine for climbing trees orwalls or fences: holds on like ivy.Medium green, heart-shaped leavesare beautiful, but different intexture and scale. Large-leaved deciduous foliagewill cover like ivy in summer, andcinnamon-red shaggy bark offerswinter texture. Unlike ivy, it has beautiful laceyhydrangea-like blooms of creamwhite in June which are good fordried arrangements. Plant is relatively disease free andeasy to care for. USDA zones 4-8Image courtesy of Monrovia NurseryMore choices: silvervein creeper (Parthenocissus henryana), minature London pride (Saxifraga‘Primuloides’), bearberry (Cotoneaster dammeri), wintercreeper (Euonymus fortunei), boxleafhoneysuckle (Lonicera pileata), sweetbox (Sarcococca hookeriana var. humilis), Boston ivy (Parthenocissustricuspidata) and natives beach strawberry (Fragaria chiloensis) and evergreen violet (Viola sempervirens).
a q u at i c & w e t l a n d p l a n t sFlowering Rush - Butomus umbellatuseivsvanIIntroduced to ponds and waterRecommended Alternative 18 gardens for its clusters of pretty pinkflowers, flowering rush has become anaggressive invader in freshwater habitats. Thisperennial can grow submersed or emerging fromwater, as well as in wetlands and shorelines. Itspreads readily by rhizomes, rhizome fragments,bulbils (bud-likestructures), and seeds. Flowering rushoutcompetes native plant species, severelydegrading habitat for wildlife and nativefish. Dense stands may provide coverfor introduced predator fish that eat ournative fish species. These stands can alsoimpact our swimming and boating areasand can clog unlined irrigation canals andImage courtesy of Laurel Baldwindrainage ditches.class A Washington state noxious weedHardstem bulrushSchoenoplectus acutusThis native perennial species growsin patches of striking uprightstems. It is ideal for growing at the edgesof ponds, lakes, and wetlands.Plants can grow in areas ofseasonally flooding. Stout, dark green stems grow 3 to10 feet tall. A few leaves may bepresent at the base of the stems. Small infloresences at the stemtips are golden brown and formseeds. Stands of this native species helpprovide erosion control alongshorelines. USDA Zones 3-9.Image Courtesty of Max Licher, SEINet,CC BY-SA 3.0
Recommended AlternativeDouglas’s asterSymphyotrichum subspicatumA native perennial with purple toblue flowers. Leafy stems grow from rhizomes,growing to 3 feet or taller. Blue to purple daisy-like flowersbloom from summer to fall. Excellent plant in your garden forpollinators It grows in wet soils and full sunto part shade. USDA zones 6-9Recommended AlternativeMarsh cinquefoilComarum palustreThis native perennial grows in wetareas and has striking red flowers. This widely distributed nativeis found in bogs, fens, lake andpond edges, wet meadows, andstreambanks. Growing from rhizomes, stemsform a groundcover or even afloating mat when it has grownover the water’s edge. Hairy leaves are divided, with 5to 7 toothed leaflets, and are lightgreen to almost light blue in color. Deep red to purple flowers bloomin the summertime. USDA Zones 3-7.Image courtesy of Jenifer ParsonsMore choices: smallfruited bulrush (Scirpus microcarpus), bogbean (Menyanthestrifoliata). 19 Image courtesy of Al Keuter, CC BY-NC-SA 3.0, 2013
w e t l a n d a n d a q u at i cYellow Flag Iris - Iris pseudacoruseivsvaWith its showy yellownIflowers and dense, lance-Recommended Alternative 20 shaped leaves, yellow flagiris has been a popular additionto ornamental ponds and watergardens. However, this emergentwetland plant quickly spreadsthrough underground rhizomes andrhizome fragments. It naturalizesalong streams, canals, andshorelines in Washington. Yellowflag iris can completely out competenative wetland plants along theshoreline, and its dense, root-likemat collects sediment and severelyreduces water flow, affecting plants,fish, and other animals.Class C Washington State Noxious WeedJapanese IrisIris ensata cultivars including ‘Variegata’These are beautiful irises for pondedges and bogs. They are ideal for wet boggy areasand edge-of-pond plantings, easyto grow. Elegant large flowers of white,purple, and violet blue form inlate spring and early summer, alittle after yellow flag iris. Foliage can reach 16 inches, thescale of the plant is smaller thanyellow flag iris. The foliage of the cultivar‘Variegata’ offers a creamy whiteand green foliar accent to pondplantings. USDA zones 5-8Image courtesy of Laura Burton
Recommended AlternativeLaevigata IrisIris laevigata & cultivarsA true water-loving iris, beautiful inand out of flower. An ideal replacement for yellowflag iris in pond plantings,laevigata iris grows well in 6inches of water. It is also good forwet boggy areas, and it’s easy togrow. Flowers are large white, purple,lavender, and pink. Yellowblooming cultivars are rare. Blooms later than yellow flag iris. Foliage can reach 18 inches, sothe scale of the plant is smallerthan yellow flag iris. USDA zones 2-9Recommended AlternativeSiberian IrisIris sibirica & hybrids such as ‘Butter & Sugan’, ‘Sunfisher’(both yellow blooming)A very versatile, easy-to-grow iris:the one to choose, other than abearded iris, if you want yellowflowers.‘Butter & Sugan’, ‘Sunfisher’ Good for mixed borders withnormal water needs; also suitablefor damp sites, but not forstanding water. Flower colors range from white topurple to blue-purple to yellow. With foliage usually 2 feet or less,and taller flowers, the plant issmaller than yellow flag iris. Blooms May-June, but its lovelyfoliage makes this iris beautiful inand out of bloom. USDA zones 4-9Image courtesy of Todd BolandMore choices: Arctic iris (Iris setosa), blue flag irises (Iris versicolor and Iris virginica),bearded iris (Iris x germanica), and native species Rocky Mountain iris (I. missouriensis),western skunk cabbage (Lysichiton americanum). 21 Pat Woodward, Pacific Rim Native Plant Nursery
W e t l a n d a n d a q u at i cFragrant Water Lily - Nymphaea odorataeivsvanIAlthough native to the eastern half of the United States,Recommended Alternative 22 fragrant waterlily has been deliberately introduced into pondsand water gardens in the Pacific Northwest because of its largeand beautiful,sweet-smellingwhite flowers.However,this floatingleaved plantcan quicklydominate thewater, denying submerged aquaticvegetation light and oxygen,stagnating water flow, degradinghabitat for fish and invertebrates,and restricting wildlife andImage courtesy of Stevens County NWCBhuman access to water bodies.Class C Washington State Noxious WeedFragrant Waterlily cultivarsNymphaea ‘Lucianna’,N. ‘Pink Beauty’, N. ‘Hermine’These fragrant waterlilies are idealfor contained water gardens. Less aggressive cultivars ofNymphaea, such as the Marliaccultivars, come in a wide range ofboth bold and subtle colors. These water garden plants shouldnot be placed in natural ponds,lakes, streams, or rivers wherespread may be a danger ora problem. USDA zones 3-11Courtesy of Erv Evans,North Carolina State University
Recommended AlternativeWater ShieldBrasenia schreberiA native aquatic plant with smallfloating leaves. Floating oval leaves are dark greenon top and purple underneath. Water shield grows in water 2-6feet deep. Found in lakes around westernWashington, water shield is safeto use in natural water bodies toreplace fragrant waterlilies. The small, dark purple flowersthat appear in late summer areattractive but unlike fragrantwater lilies’ showy blooms. Fish and other wildlife use thisplant for valuable food and shelter.Recommended AlternativeSpatterdockNuphar polysepalaA large native aquatic plant foundin a range of water depths. Floating leaves on stiff stemssometimes lift above the waterduring low water levels. The showy yellow flower isdissimilar to fragrant waterlily’slotus-like bloom, but no less eyecatching. This native plant is foundin ponds and lakes aroundWashington and is an importantsource of food and shelter forlocal fish and wildlife.Image courtesy of Ben LeglerPlease remember, never dump water garden, aquarium plants, oraquarium fish into natural water systems. 23 Image courtesy of Whatcom County NWCB
Identify it early and nip it in the bud! Penstemon species There are many beautiful, native penstemon species that can grow in your garden. Penstemons are typically short-lived perennials that produce beautiful clusters of flowers, of colors including pink, violet, and white. Penstemons have opposite leaves and five-petaled flowers, which
