St. John’s Wort – Learn How to Choose

When bet for a low - develop native plant for the cutting edge of our perennial Lord’s Day garden , I became concerned in St. John ’s wort . Many of the sun - loving natives in our garden are tall and run to become leggy as the growing season progresses . St. John ’s wort seemed to be a possible native filler plantthat could hide the leafless bottom fate of marvellous flora staunch .

When I asked gardeners about the pros and sting of St. John ’s wort , they gave motley followup . Some said that the foreign-born species are invasive ; some say even the native species are encroaching . There even seemed to be mix-up about which metal money are aboriginal . After beginning my inquiry , I actualise that one reason for the confusion is that there arealmost 500 dissimilar species ofHypericum , many of which are normally referred to as St. John ’s wort . plant of the genusHypericumwere apparently pile up and burned to ward off evil spirit on the eve of St. John ’s Day , thus establish rise to the genus common name of St. John ’s wort . To avoid the confusion of overlap usual names for different species , it is advisable to utilise the Latin name when identifyingHypericumfor purchase .

Daunted by the prospect of almost 500 different coinage including perennials , tree , and shrubs , I determine to consult two main generator to identify theHypericumspecies native to our area : thePiedmont Virginia Native Plant Databaseand theNative Plant Finder By Zip Code .

The Piedmont Virginia Native Plant Database heel onehypericumnative to our area : shaggy St. John ’s wort or dense St. John ’s wort ( Hypericum densiflorum ) .

The Native Plant Finder By Zip Code cites 5 species ofHypericumthat are native to energy code 22901 :

In addition to thesesix native specie , I will also covertwo additional foreign-born speciesthat are normally notice in glasshouse in our area : genus Hypericum perforatumandHypericum calycinum .

NONNATIVEHYPERICUMSPECIES

Hypericum perforatum

Common St. John ’s wort or perforate St. John ’s wort(Hypericum perforatum ) is native to Europe , North Africa , and Southwest Asia . It is also commonly calledgoatweed or Klamath weed .

Plants were first brought to North America by settler in 1696 and have naturalise over clip throughout much of the continent . H. perforatumis classified as anoxious weedin over 20 rural area . In the U.S. , it is classified as an trespassing or noxious weed in several states include Oregon , California , Washington , Montana , Nevada , Utah , Wyoming , West Virginia , and Indiana . It is also heel on Alaska ’s list of alien plant .

The specie grows 1 - 3 ’ tall . It has pocket-sized , geminate , ovate leave . Most leaves have scatter , petite translucent dose ; when control up to the light , they give the impression that the leaf is punch ( where the scientific name come from ) . Yellow , principal - shaped , ¾ ” blossom are 5 - petaled with many stamens and have tiny fatal acid around the edge . ( See dose in the picture above . ) Flowers bloom in June - August . The foliation has an unpleasant aroma when bruised or rubbed . Although kind of most soil types , the plantprefers moist , well - drain filth . The species can grow in either full sun or in partial shade , but it flowers more profusely in full sun . It circularize by rhizomesand , once established , it can behighly invasiveand very difficult to remove . Its seed can be dispersed by idle words , water , human , and other animals . Seed can lie sleeping in the soil semen bank for many year and spud once the soil is disturbed . As an invasive , common St. John ’s wort can replace aboriginal plants in natural ecosystem .

The compound , hypericin , is found in stems , leaves , flower , and seeds , and cause blistering and itch on tripping - haired or unpigmented skin exposed to vivid sunlight . When an animal eatsH. perforatum , hypericin reaches the skin from an internal route ( stomach to blood to skin ) . It thensensitizes lily-white or unpigmented skin to sunlight and causes lesions . In large dot , it is toxicant to farm animal , especially horses and kine .

Hypericumshave historically been used as herbal medicine , butH. perforatumis the one most unremarkably used today . Althoughtoxic , H. perforatumhas been used to treat people for economic crisis , nervousness , and insomnia . It has been used externally to treat underage wounds , inflammations , burns , skin disorders , and cheek pain . It is blackball in France and is useable only by prescription in many other land . concord to the NIH National Center for Complementary and Integrative Health : “ It has been understandably bear witness that St. John ’s wort can interact in dangerous , sometimes life - threaten way with a variety of medicines.(See thisNIH linkfor more information on toxicity and condom warnings . ) It is sold in the U.S. as a dietary appurtenance ; such supplement have lower standards for favourable reception than over - the - counter medicines .

Hypericum calycinum

Commonly calledAaron ’s Beard or pussyfoot St. John ’s wort , Hypericum calycinumis native to Southern Europe and southwest Asia . Thisstoloniferous subshrubor shrublet typicallygrows to 12″ ( less frequently to 18″ ) mellow and 24″ wideand is frequentlyplanted as a ground binding . orotund , 5 - petaled yellow flowers are about 3 ” with numerous , erect stamens that give a powder - puff visual aspect in summer . AlthoughH. calycinumtolerates a wide range of soils , it fly high in sandy soils in full sun;it is less floriferous in part tincture . In full sun , the 4 ” long leave of absence are a rich commons ; in ghost , they are a lighter , yellowish fleeceable ; in declivity , the leaves release purplish . This speciesspreads apace by underground stemsand can spread sharply in ideal growing conditions , such as inOregon , where it is listed as aninvasive . It is not list as an invasive industrial plant by the United States Department of Agriculture , andit is not toxic . Once install , it can be unmanageable to remove . In addition to spreading by rhizomes , its tap root and upright roots can gallop 5 ’ cryptical . wilt disease and solution rot can be substantial problem , specially in hot and humid clime of the South .

HYPERICUMSPECIES NATIVE TO OUR arena

Hypericum densiflorum

Bushy St. John ’s wort(Hypericum densiflorum ) is a native bush that cangrow up to 6 ’ tallwith a spread of3 - 6 ’ wide . It is native to eastern U.S. and Occident to Texas and occurs onacidic soils in moist and besotted condition , including streams , pool , lake bank , seepage slopes , and wet meadow . It is adaptable to a variety of moisture level and , once established , has some drought underground . It digest a miscellanea of soil types , including cadaver , loam , Amandine Aurore Lucie Dupin , and shallow rocky ground . Beautiful , exquisitely - textured foliage turns yellow / gold in fall . cluster of 5 - petaled , yellowish efflorescence with multiple stamens appear in dense , flat - topped cymes from June - September . Flowers give fashion to interesting cone cell - shaped pods which split in the fall and persist all wintertime . The glossy , coppery - colourize bark of mature shrub adds optic interest to the wintertime landscape painting . This shrub is well grown in median , well - drained , moist garden soil in full sun to fond shade . Plant in groups , shrub border , foundation , or as a hedge . It works well in a native / pollinator garden , a rock music garden , or on slopes for erosion control . It is in the main free of blighter and diseases .

According to theInvasive Plant Atlas of the United States , this specie does not appear on any nation or national encroaching species lists . According to theChesapeake Bay Foundation , it can spread out sharply , so be sure to provide room if you choose this coinage .

Hypericum prolificum

Shrubby St. John ’s wort(Hypericum prolificum ) is a modest , hummock - regulate , deciduous shrub growing2 - 4 ’ tall , with dense , upright branching . The low-spirited stem are woody with sliced gray - brownish barque , while the upper stems are gullible . The root organisation is woody and branching . Dark light-green , lance - forge leaf are 2 - 3″ long and turn yellow - common in fall . Bright white-livered , 5 - petaled flowers ( to 1″ diameter ) have legion , yellow stamens . stamen are bushy to the point of partially obscuring the petals ( hence the species name ofprolificumwhich refers to the stamen ) . Flowers seem from June - August . Each flower is replace by a strobilus - shaped seed ejector seat about 1/3–1/2″ in length , which cleave in autumn to release opprobrious seeds . The bloom are cross - pollinate primarily by humblebee , which collect pollen for their larvae . Sometimes butterfly stroke and wasps land on the flowers in lookup of nectar , but the flowers declare oneself only pollen . Caterpillars of the butterflyStrymon melinus(gray hairstreak butterfly ) give on the germ capsules , and caterpillars ofNedra ramosula(gray half - spot ) , and other moth , feed on the leave of absence . This native industrial plant go on on bouldery ground , dry wooded slopes , artless fields , gravel parallel bars along watercourse , and in low , moist valleys . It tolerates a wide-cut range of soils , let in dry bouldery or sandy dirt , and it can arise in full sunshine to part shade . It also tolerates some drouth . Although it has no serious disease or insect problem , root buncombe and wilt can be pregnant problems in hot and humid climates . Mass or mathematical group this species in the shrub mete , include it in a native plant garden , or arise it as a hedgerow . It is also utilitarian for stabilizing embankments . According to the list compiled by Rutgers on“Landscape Plants rat on Deer Resistance,”H. prolificumearns a B , which is “ rarely severely damage . ”

According to theInvasive Plant Atlas of the United States , this metal money does not appear on any nation or national invasive species list .

Hypericum punctatum

Spotted St. John ’s wort(Hypericum punctatum ) is aperennial herb that grows up to 2 ½ ’ grandiloquent , branch now and again in the upper one-half . Hairless , tumid stems are multiple from the base and mostly unbranched , except in the bloom cluster . Hairless , polar leaf are up to 2½ ” long and 1″ across . They are oblong , oval , or bluntly lanceolate ( with rounded tips).New leave are heavily dotted with black glands around the boundary and on the bottom . ( The invasive metal money , H. perforatum , has semitransparent Department of Transportation on the leaves . ) Tight clusters of icteric flowers bloom during June 21 , and the bloom period lasts for about a month . Each flower is a piddling less than ½ ” across and has 5 petal . In the center , a flask - shaped pistil is surround by numerous yellow anther on farseeing styles . The easiest way to distinguish spotted St. John ’s wort from other like species call for an examination of the flower flower petal . For spotted St. John ’s wort , dark dots and streaks can appear anywhere on the upper open of the yellow flower petal , whereas for other coinage of St. John ’s wort , such superman and streak are confined near the margins of the flower petal , or they are totally absentminded . There is no flowered scent . The plant cangrow in full or partial sun ; moist to mesic ( temperate or well - balanced supply of moisture ) shape ; and a rather skimpy dirt , which trim down competition from taller plant . bouldered or gravelly soil is quite acceptable . from time to time , the leaves turn brown in answer to drouth ; otherwise , this plant has few problems .

H.punctatumis pollinated by insects and has special value to humblebee and fret bee . It also attract mallet and hoverflies although these dirt ball pollinate to a less extent . Its flowers do not produce nectar ; insects are attracted by the pollen . Gray hairstreak caterpillarsfeed on the seeded player capsule andgray half - spot caterpillarsfeed on the leaves . Though insects corrode the plant , foraging mammals rarely prey on the foliage which hold hypericin .

legion lilliputian seeds are scattered by the wind when the stems sway back and forth . The root system consists of a separate taproot and short rhizomes . Although vegetative settlement of this works can develop from the rhizomes , I did not find any warning on invasiveness .

Hypericum crux - andreae

St. Peter ’s wort ( Hypericum crux of the matter - andreae)is a small , uprightshrub that grows1 - 3 ’ tallwith4 - petaled bloom , instead of the usual 5 flower petal generally characteristic of other St. John ’s worts . ( This Latin name is right , even though it seems to go with St. Andrew ’s mark . ) Thesepalsare of very unequal sizes . Brilliant maize - jaundiced flowersform at its branch tips , and bloom from June - October . The slender shrub has diametrical , pale green , oval - to - oblong leaves about 3/4 ’’ widely , and spill barque on older Mrs. Henry Wood . In its native home ground , this shrub is usually find inmoist sandy wood , pinelands , current banks , sloshed prairies , and pool security deposit . It can also appear in worried fallow fields . Seed dispersion is thought to be by gravitational force . It prefers partial sun and is adaptable to different soils . It cast from New York south to Florida and west to Texas ; in the northward , it may shape a matte on the priming . St. Peter ’s wort is critically imperiled in Florida , according to the Institute for Regional Conservation . accord to the U.S. Department of Agriculture , it has disappear from Pennsylvania , and Kentucky lists it as jeopardise . H. crux - andreaehas been observed to host skipper such asPanoquina ocola(family Hesperiidae ) .

I did n’t detect any mention of invasiveness , nor was this species include on invasive leaning .

genus Hypericum hypericoides

St. Andrew ’s cross(Hypericum hypericoides ) is asmall shrub growing 1 - 3 ’ marvelous . The common name have-to doe with to St. Andrew , the patron saint of Scotland , who is say to have been martyrise by crucifixion on an x - shaped cross . Theflowers are small ( < 1 ” ) andcreamy yellow with four narrow petalsarranged in an “ X. ” ( The 4 petals are narrower than those of St. Peter ’s wort . ) The prime have many large yellowish stamen and 4 inadequate sepal . It blooms from July - October , although in some zone its bloom period is given as May - August . Leaves are diametric and may be analogue , oval-shaped , or ovate , and up to 1/3 ” widely , which is narrow than the leave of St. Peter ’s wort . Stems are branch and reddish - brown . fruit are reddish - brown ovoid ejection seat . Propagation is by seed and dispersal is generally think to be by gravity ; some seeds were discovered in a 112 - yr - erstwhile airfield site . preferent website are wet to moderately dry , well - drained , or calcareous soil in fond sun . It graze from New York to Florida and west to Texas . It is sometimes found in the same home ground as St. Peter ’s wort . This species is do it to beeaten by white - tailed deer , mostly during the winter . On the state level , H. hypericoidesis considered vulnerable in the state of Delaware .

grant to theInvasive Plant Atlas of the United States , this speciesdoes not appear on any state or internal trespassing species lists .

Low St. Andrew ’s Cross ( H. suffruticosum)is only 2 ½ – 6 ” marvelous , with usually only 2sepals , the flowers eventually nodding ; it is found in flaxen site in the coastal field from South Carolina to the south to Florida and west to Louisiana .

Hypericum gentianoides

Orangegrass or pineweed(Hypericum gentianoides ) is the onlyannualSt . John ’s wort from our list . With tiny white-livered flowers that open only in the sun , and scaly leave on erect , stringy branch , its appearing is also unlike other St. John ’s worts . Generally , H. gentianoidesflowers from July - October ; however , it has been observe inflorescence in May through July and September . Its seed capsules are usually red . It proliferates in fields , tilt outcrops , timber borders , wear away area , pond margin , and flatwoods . Although it most often occurs in non - wetland home ground , it can also occasionally be see in wetland habitats . It mostly maturate in open arena with sandy or rough stain ; it can also tolerate partial shade . It is circularize from Maine and Ontario Dame Rebecca West to Minnesota , and south to southerly Florida and Texas . It circularise by seed which is believed to be dispersed by graveness . When crushed , its leaf give off a citrus feel .

H. gentianoidesis listed as endangered by the Iowa Department of Natural Resources Parks , Recreation , and Preserves Division . It is also consider vulnerable in Michigan , threaten in Vermont , critically imperiled in Oklahoma and Ontario , and is anexotic species ( not aboriginal ) in the Canadian province of New Brunswick , Nova Scotia , and Prince Edward Island .

It is not admit on invasive lists for the U.S. However , its listing as an alien species in the three Canadian province observe above plus Ontario , indicates that it may have worrisome invading characteristics .

HYPERICUMIN THE FOOD WEB

According to theNative Plant Finder by Zip Code , Hypericumspecies that are aboriginal to zip code 22901 are thelarval host plants for 23 species of butterflies and moth . Hypericumspecies are attractive to many native bee include : polyester , yellow - face , large carpenter , bumble , leafcutter , resin , and sweat bee , as well as to gray hairstreak butterflies , whose caterpillars give on the cum capsule , and to grey half - spot moths , whose caterpillars feed on the leaf . Hoverflies and skippers are also attract to some species . ShrubbySt . Johns wortproduces seeds that persist all wintertime , making it a favorite of finches and sparrows .

SUMMARY

TheHypericumgenus is a fascinating collection of plants comprising almost 500 species . The research for this article was done with the linear perspective of identify aboriginal species that might be used in home landscape . I was particularly concerned in identifying species that would be respectable “ makeweight ” plants in the lower stratum of perennial garden . After my enquiry , the two non - nativeHypericumsarenot attractive as potential accession to the landscape : H. perforatumis very invasive , andH. calycinummay be invasive , especially in conditions that are attractive to the industrial plant . Unfortunately , these are theHypericumspecies that seem easiest to purchase .

Of the native species , there are a few candidates for household landscaping that could be very attractive , calculate on your landscape ’s wet and sunshine conditions , and available space . Most specie are describe as being adaptable . H. densiflorumis attractive as a large - sized bush , if there isenough space for it to distribute . It has attractive leaf , sound fall color , a long bloom geological period , and attractive seminal fluid pods and interesting bark for winter interest . It does well in moist and stiff condition . H. prolificumis a small bush that does not come along to have spreading characteristics . It has a long bloom period , and performs well in a range of soil , moisture , and light conditions . ( This species sound promise although it can grow to 4 ’ tall.)H. punctatumseems like a possible candidate for the filler layer . It ’s aperennial herb that grows to 2 ½’and has a long bloom menstruum . It ’s adaptable to a range of conditions except for drought . It is attractive to bee . It does contain hypericinwhich may be a trouble for pawl or cats who eat plants . The hypericin message means it will be deer resistant . H. crux - andreaeis a little shrubthat likesmoist stipulation in partial sun . H. hypericoidesis a lowly shrub that like semi - fly-by-night , wet- to moderately - ironical domain . Neither of these shrubs are invasive . regrettably , H. hypericoidesis susceptible to deer browsing . Theannual species , H. gentianoides , is chiefly found indry areas with sunlight . It is list as an exotic metal money ( nonnative ) in several eastern Canadian province which intend it must have some invasive characteristic in those areas . The availability of these lesser - hump coinage might be a challenge . work with local native plant greenhouse would be the most bright approach .

SOURCES

Piedmont Virginia Native Plant Database , http://webapps.albemarle.org / NativePlants / list.asp

Native Plant Finder by Zip Code , https://www.nwf.org / NativePlantFinder / Plants/1707

“ Hypericum perforatum , Common St. John ’s Wort , ” Minnesota Wildflowers , https://www.minnesotawildflowers.info / flower / mutual - st.-johnswort

“ Hypericum perforatum , ” Royal Horticultural Society , https://www.rhs.org.uk / plants/9021 / genus Hypericum - perforatum / details

“ St. Johnswort : designation , Biology , and Integrated Management , ” Montana State University Extension , https://apps.msuextension.org / montguide / guide.html?sku = MT199810AG

“ St. John ’s Wort , Hypericum perforatum , ” National Center for Complementary and Integrative Health ( NIH),https://www.nccih.nih.gov / health / st - johns - wort

Common St. John ’s Wort , Hypericum perforatum L. , Invasive.org . ,https://www.invasive.org / browse / subinfo.cfm?sub=4411&start=1

‘ Hypericum calycinum , NC State Extension , https://plants.ces.ncsu.edu / plants / hypericum - calycinum/

“ Aaron ’s Beard , Hypericum calycinum L. , Invasive Plant Atlas , https://www.invasiveplantatlas.org / subject.html?sub=18314

“ Hypericum calycinum , ” Missouri Botanical Garden , http://www.missouribotanicalgarden.org / PlantFinder / PlantFinderDetails.aspx?kempercode = a520

“ genus Hypericum densiflorum , Bushy St. John ’s Wort , ” NC State Extension , https://plants.ces.ncsu.edu / plant / hypericum - densiflorum/

“ Hypericum densiflorum , Bushy St. John ’s Wort , ” Mt. Cuba Center , https://mtcubacenter.org / plants / bushy - st - johns - wort/

“ Hypericum densiflorum , ” Chesapeake Bay Native Plant Center , http://www.nativeplantcenter.net / works / genus Hypericum - densiflorum/

“ Spotted St. John ’s Wort , Hypericum punctatum , ” Illinois Wildflowers , https://www.illinoiswildflowers.info / prairie / plantx / sp_stjohnwortx.htm

Spotted St. , John ’s Wort , Hypericum punctatum , Minnesota Wildflowers , https://www.minnesotawildflowers.info / flower / pick out - st.-johns - wort

“ Shrubby   St. John ’s Wort – Hypericum prolificum , ” Illinois Wildflowers , https://www.illinoiswildflowers.info / prairie / plantx / sh_stjohn.htm

“ Flower Friday : St. Andrew ’s Cross , Hypericum hypericoides , “ Florida Wildflower Foundation , https://flawildflowers.org / flower - friday - hypericum - hypericoides/

“ Hypericum hypericoides,”Ladybird Johnson Wildflower Center , https://www.wildflower.org / plants / result.php?id_plant = HYHY

“ Hypericum Southern Cross - andreae , St. Peter ’s Wort , ” Lady Bird Johnson Wildflower Center , https://www.wildflower.org / plants / result.php?id_plant = HYCR3

“ St. Peter ’s Wort , Atlantic St. Peter ’s Wort , ” Texas Native Plants Database , Aggie Horticulture , https://aggie - horticulture.tamu.edu / ornamentals / nativeshrubs / hypericumcrux.htm

“ St. John ’s Wort , or St. Peter ’s Wort , or St. Andrew ’s Cross ? ” NC Cooperative Extension , https://lee.ces.ncsu.edu/2018/11 / st - johns - wort - or - st - peters - wort - or - st - Roy Chapman Andrews - cross/

“ genus Hypericum gentianoides , ” Lady Bird Johnson Wildflower Center , https://www.wildflower.org / plant / result.php?id_plant = HYGE

“ Pineweed ( orange grass),Hypericum gentianoides , Connecticut Botanical Society , https://www.ct - botanical - society.org / Plants / view/283

“ Hypericum gentianoides,”University of Michigan LSA Herbarium , https://michiganflora.net / species.aspx?id=1461

Indiana Invasive Species Council , https://www.invasive.org / species / list.cfm?id=167

California Invasive Plant Council , https://www.invasive.org / species / list.cfm?id=64

Montana Noxious Weeds , https://www.invasive.org / species / list.cfm?id=38

Oregon Noxious Weeds , https://www.invasive.org / species / list.cfm?id=56

Nevada Noxious Weeds , https://www.invasive.org / species / list.cfm?id=29

Alaska Exotic Plant Information Clearing List , https://www.invasive.org / species / list.cfm?id=86

Utah Noxious Weeds , https://www.invasive.org / species / list.cfm?id=33

Washington Noxious Weeds , https://www.invasive.org / species / list.cfm?id=61

West Virginia Invasive Species Strategic Plan and Volunteer Guidelines 2014,https://www.invasive.org / species / list.cfm?id=184

Wyoming Noxious Weeds , https://www.invasive.org / species / list.cfm?id=40

“ St. John ’s Wort , Friend or Foe ? ” myMotherLode.com , https://www.mymotherlode.com / news / local/310245 / st - johns - wort - Quaker - or - foe.html

“ A Review of Some Biological Control Programs for Invasive Plants , ” Ontario Invasive Plant Council ( pp.21 - 28),https://www.ontarioinvasiveplants.ca / wp - subject matter / uploads/2016/06 / Bill - MacIlveen-1.pdf

Feature Photo : shrubby St. John ’s wort ( Hypericum prolificum ) Photo : Susan Martin , Ivy Creek Natural Area , Charlottesville , VA