Organic Solutions for Colorado Potato Beetles

A Factsheet from Toxic Free NC

AboutColoradoPotatoBeetlesTheColoradopotatobeetleisacommonpestofthe“nightshade,”orSolanaceaefamilyofplants.Theseincludepotatoes,tomatoes,eggplants,toma<llos,tobacco,peppersandpetunias.Bothadultsandlarvaeeattheleavesoftheseplants,andcankillalotofleaves,hur<ngtheplantorevenkillingit.Coloradopotatobeetlesareverydifficultpeststocontrol.Theyhavedevelopedresistancetomostpes<cidesandhavefewnaturalenemies.The<psbelowaredesignedtohelpyoumanagethepestsiftheybecomeaprobleminyourgarden.Sustainablepestmanagementstrategiesusuallyworkbestwhenusedtogether.Thinkaboutyourgarden,yourresources,andyour<me,andputseveralofthese<pstogetherforaplanthatworksforyou.Iden2fyingColoradoPotatoBeetlesAdultColoradopotatobeetlesareovalshapedandabout1/3inchlong.Theyareyellowish-orangewith10boldblackstripesrunningdownthelengthoftheirbacks.LarvaearesoI-bodied,humpbacked,andreddish-orangewitharowofblackspotsalongtheirsides.Eggsarelaidinclustersontheundersidesofleavesandarebrightyellow.LifeCycleAdultColoradopotatobeetleshibernateinthesoilinandaroundthegardenallwinter,andcomeouthungryandreadytoeatintheearlyspring,justasthepotatoplantsarecomingup.AIerma<ng,theylaytheireggsontheundersidesofleaves.Theeggshatchin5-10daysandthelarvaeeatplantleavesfor2-3weeksbeforediggingbackintothesoiltopupate.Thereareusually2-3genera<onsperyear.

LifecycleofaColoradopotatobeetle.Photocredit:ArtCushman,USDA;PropertyoftheSmithsonian

Ins<tu<on,DepartmentofEntomology

Coloradopotatobeetleeggshatchingwithbrandnewlarvae.Photocredit:WhitneyCranshaw,ColoradoStateUniversity

Preven2on1)Growhealthyorganicplants.Strong,healthyplantscanhandlesomedamagefromColoradopotatobeetlesbeUerthanweak,strugglingplants.MakesurethatyourcropsaregeWngenoughsunlightandwaterandthatthesoiliswell-drained,richinnutrients,andhasplentyoforganicmaUer.Researchhasshownthatpotatoplantsgrowinginsoilfer<lizedwithmanurearelesslikelytobeaUackedbyColoradopotatobeetlesthanthosegrowninsoilfer<lizedwithchemicalfer<lizers.2)Plantearlyvarie2es.Bychoosingapotatovarietythatmaturesinlessthan80days,youmaybeabletoavoidthesecondgenera<onofColoradoPotatoBeetlesthatcomesoutinthesummer.Checkseedcatalogsforthebestvarie<esandmaturitydatesforyourarea.3)Mulchwithstraw.Athicklayerofstrawmulchunderneathyourcropcanconfuseadultpotatobeetlesthatarecomingupoutofthesoiltoeat,makingitharderforthemtofindyourplants.4)Userowcovers.KeepColoradopotatobeetlesfromfindingyourcropbycoveringyourplantswithalightweight“floa<ng”rowcoversuchasReemay.Thesematerials(asopposedtoplas<corheavierfabrics)allowwater,air,andsunlighttogetthrough.Theycanbefoundatgardensupplystoresororderedfromseedcatalogs.Thecoverscanliedirectlyontheplants(theplantswillliIthecoverastheygrow),oryoucansupportthecoverswithwirehoops.Thetrickistokeeptheedgesofthecovers<ghtlyburiedorweightedsothattheColoradopotatobeetlescannotgetin.CoveringyourcropworksbestinsoilwhereColoradopotatobeetlehasnotbeenapestinthepast.Ifyouhaveadultsspendingthewinterinyoursoilalready,rowcoverswillkeepthemininsteadofout!

Coloradopotatobeetleeggs.Photocredit:DavidCappaert,MichiganStateUniversity

CloseupofColoradopotatobeetlelarva.Photocredit:JessicaLawrence,EurofinsAgroscienceServices

GeFngRidofColoradoPotatoBeetlesWithoutToxicChemicals1)Scoutandhandpick.HandpickingColoradopotatobeetlesandtheirlarvaeearlyintheseasoncangreatlyreducetheirnumbers-everybeetleyoukillintheSpringisonethatwillnotmakebabybeetleslater!Keepacloseeyeonyourplants.InspectoIenbylookingattheundersidesoftheleavesforeggclusters,andatthe<psofnewgrowthforlarvae.

2)Planta“trap”crop.Atrapcropisoneplantedtolurethebeetlesawayfromyourmaincrop.Forinstance,ifyouhavehadaproblemwithColoradopotatobeetlesonyourtomatoesinthepast,nextyearplantpotatoesontheedgeofthegardenearlyintheseasontolurethebeetlescomingoutintheearlyspring.Later,butbeforethefirstgenera<onofnewlarvaeheadsundergroundtopupate,killthe“trap”potatoplantsalongwiththepestsbysealingthemalltogetherintogarbagebagsandleavingtheminthesuntobakeforafewdays.Then,plantyourtomatoesinanotherpartofthegarden.3)APractnaturalenemies.EventhoughtheColoradopotatobeetlehasfewnaturalenemies,itcan’thurttohosttheonesthatdoexist!AUractbeneficialinsectsandotherhelpfulcreaturestoyourgardenandthey’lldosomeofthedirtyworkforyou.Pollenandnectarplantswithsmallflowers,suchaswildflowersandherbs,willaUractparasi<cwasps.Birds,spidersandpredatorybeetlesliketoliveinperennialherbandflowerbedsandsmallshrubsnearthegarden.4)Bringinpredators.Spinedsoldierbugs,parasi<cwasps,andparasi<cnematodesthatwillaUacktheadults,larvae,orpupaeofColoradoPotatoBeetlescanbeboughtandreleasedintothegarden.Checkgardeningandseedcatalogsforproperspeciesandinstruc<ons.5)Bioinsec2cideBTSD.BTSD(Bacillusthuringiensis,var.sandiego)isatypeofbacteria.WheneatenbytheColoradopotatobeetlelarvae,BTSDproducesapoisoninthepest’sgut.Thelarvaewillstopea<ngandeventuallydie.BTSDisselec<ve,whichmeansitwillkillmanyleaf-ea<ngbeetleswithouthur<ngbeneficialinsectslikepollinators.Itmustbeeatenbythelarvaetowork,sosprayitontheleavesofplantswheretheyarefeeding.TofindBTSD,checkgardeningandseedcatalogs.MakesuretochecktheBTSDproductyouselectisontheOrganicMaterialsReviewIns<tute’slistofproductsapprovedforcer<fiedorganicfarms.Becausecutwormsspendmostoftheir<mehidingunderground,theuseofotherinsec<cidesisnotrecommendedforcutwormcontrol.

DamagefromColoradopotatobeetlelarva.Photocredit:USDAAPHISPPQArchive,USDAAPHISPPQ

AdultColoradopotatobeetle.Photocredit:C.Trouvé,ServicedelaProtec<ondesVégétaux

6)Otherorganicallyacceptableinsec2cides.Asalastresort,youmightchoosetoapplyleast-toxicinsec<cidesthatareOMRIapproved.insec<cidesareusuallyonlyeffec<veinslowingdownColoradopotatobeetles,notstoppingthem.Organicfarmersweaskedrecommendspinosad,andothertypesincludepyrethrin,Neemoil,orinsec<cidalsoap.Eventhoughthesespraysareapprovedforcer<fiedorganicfarms,theycanbeharmful.Besuretofollowinstruc<onsonthelabelsverycarefully.Theseproductscankill“goodbugs”youwanttokeepinyourgarden,souseasliUleasyoucan,andsprayonlyintheearlymorningorlateeveningwhen“goodbugs”arelessac<ve.Insec<cidesusuallydon’tworkagainstadultColoradopotatobeetlesandtheireggs,buttheydokillthesoI-bodiedlarvae.Tohitthemostlarvaewithaspray,youneedtouseitsoonaIerthefirsteggshavehatched,andtotallycovertheleaves.Oneroundmaydothejob,oryoumayfindyouneedtosprayagainwhenanewgenera<onoflarvaehatch.

SourcesEllis,BarbaraandBradley,FernMarshall,editors.TheOrganicGardener'sHandbookofNaturalInsectandDiseaseControl:ACompleteProblem-SolvingGuidetoKeepingYourGardenandYardHealthyWithoutChemicals.RodalePress,1996.Alyokhin,Andrei.“ColoradoPotatoBeetleManagementonPotatoes:CurrentChallengesandFutureProspects.”Fruity,VegetableandCerealScienceandBiotechnology,GlobalScienceBooks.2009.ViewedMarch,2012:[link]Ragsdale,DandRadcliffe,E.“ColoradoPotatoBeetle.”UniversityofMinnesota:VegEdge–VegetableIPMResourcefortheMidwest.ViewedMarch,2012:hUp://www.vegedge.umn.edu/vegpest/cpb.htm“ColoradoPotatoBeetle.”Insectandrelatedpestsofvegetables.NorthCarolinaStateUniversity:CenterforIntegratedPestManagement.ViewedMarch,2012:[link]

Thisfactsheetwaswri2enwiththeneedsofnon-commercialhome,schoolandcommunitygardenersinmind.Cer;fiedOrganicgrowers,orthoseseekingacer;fica;on,shouldcheckwiththeircer;fyingagencybeforeusingANYinsec;cide.Someorganicallyacceptableinsec;cidesareapprovedforuseinCer;fiedOrganicsystemsonlyagainstcertainpestsorincertainsitua;ons.