POISONOUS PLANTS Poisonous Plants Commonly Found In Your Garden
According to the Canadian Biodiversity Information Facility (Government of Canada), the following garden plants contain one or more poisonous parts (i.e. seeds, roots). For further information, please visit www.cbif.gc.ca.
COMMON NAME BOTANIC NAME COMMON NAME BOTANIC NAME
alder buckthorn Rhamnus frangula candelabra-cactus Euphorbia lactea
alfalfa Medicago sativa caper spurge Euphorbia lathyris
aloe Aloe barbadensis cardinal flower Lobelia cardinalis
alsike clover Trifolium hybridum castor-bean Ricinus communis
amaryllis Amaryllis belladonna celery-leaved buttercup Ranunculus sceleratus
amaryllis Amaryllis vittata Chinese-lantern Physalis alkekengi
American elder Sambucus canadensis chives Allium schoenoprasum
American holly Ilex opaca chrysanthemum Chrysanthemum indicum
American mistletoe Phoradendron flavescens climbing nightshade Solanum dulcamara
angel's trumpet Datura innoxia cocklebur Xanthium strumarium
Astragalus Astragalus adsurgens Colorado rubberweed Hymenoxys richardsonii
Astragalus Astragalus lentiginosus common comfrey Symphytum officinale
Australian umbrella tree Brassaia actinophylla common groundsel Senecio vulgaris
autumn crocus Colchicum autumnale common hop Humulus lupulus
avocado Persea americana common milkweed Asclepias syriaca
bird rape Brassica campestris common privet Ligustrum vulgare
black cherry Prunus serotina common vetch Vicia sativa
black henbane Hyoscyamus niger corn poppy Papaver rhoeas
black locust Robinia pseudoacacia croton Codiaeum variegatum
black nightshade Solanum nigrum crown-of-thorns Euphorbia milii
black oak Quercus velutina cut-leaved coneflower Rudbeckia laciniata
black walnut Juglans nigra cyclamen Cyclamen persicum
black-eyed Susan Rudbeckia serotina cypress spurge Euphorbia cyparissias
blue cardinal flower Lobelia siphilitica daffodil Narcissus pseudonarcissus
blue cohosh Caulophyllum thalictroides death camas Zigadenus venenosus
blue flag iris Iris versicolor Devil's-backbone Kalanchoe daigremontiana
blueweed Echium vulgare dumbcane Dieffenbachia bausei
bog-laurel Kalmia polifolia Dutchman's-breeches Dicentra cucullaria
bracken Pteridium aquilinum eastern whorled milkweed Asclepias verticillata
broad bean Vicia faba English bluebell Hyacinthoides nonscripta
broom snakeweed Gutierrezia sarothrae English holly Ilex aquifolium
buckwheat Fagopyrum esculentum English ivy Hedera helix
bulbous buttercup Ranunculus bulbosus English yew Taxus baccata
bur buttercup Ceratocephalus testiculatus entire-leaved groundsel Senecio integerrimus
Burke's lupine Lupinus burkei European buckthorn Rhamnus cathartica
burningbush Euonymus atropurpureus European elder Sambucus nigra
caladium Caladium bicolor European spindletree Euonymus europaeus
California bluebell Phacelia campanularia false hellebore Veratrum viride
California rose-bay Rhododendron macrophyllum false ragweed Iva xanthifolia
Canada nettle Laportea canadensis February daphne Daphne mezereum
Canada yew Taxus canadensis fiddleneck Amsinckia intermedia
Canadian milk-vetch Astragalus canadensis field horsetail Equisetum arvense
candalabra aloe Aloe arborescens five-hooked bassia Bassia hyssopifolia
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COMMON NAME BOTANIC NAME COMMON NAME BOTANIC NAME
flamingo lily Anthurium andraeanum Menzies larkspur Delphinium menziesii
fly honeysuckle Lonicera xylosteum monk's hood Aconitum napellus
foxglove Digitalis purpurea moonseed Menispermum canadense
garden-sorrel Rumex acetosa morning glory Ipomoea tricolor
garland daphne Daphne cneorum mother-in-law plant Dieffenbachia seguine
garlic Allium sativum motherwort Leonurus cardiaca
gas plant Dictamnus albus naked-flowered sneezeweed Helenium flexuosum
giant dumbcane Dieffenbachia amoena narcissus Narcissus poeticus
giant hogweed Heracleum mantegazzianum northern water-hemlock Cicuta virosa
glory lily Gloriosa superba oats Avena sativa
golden-bean Thermopsis rhombifolia Ohio buckeye Aesculus glabra
golden-chain Laburnum anagyroides oleander Nerium oleander
golden-trumpet Allamanda cathartica onion Allium cepa
grass pea Lathyrus sativus opium poppy Papaver somniferum
greasewood Sarcobatus vermiculatus Oriental poppy Papaver orientale
greater celandine Chelidonium majus Osage-orange Maclura pomifera
green tansy mustard Descurainia pinnata pawpaw Asimina triloba
ground-cherry Physalis peruviana penciltree Euphorbia tirucalli
ground-ivy Glechoma hederacea Peruvian lily Alstroemeria ligtu
Guelder-rose Viburnum opulus petty spurge Euphorbia peplus
hairy vetch Vicia villosa philodendron Philodendron cordatum
heart-leaved philodendron Philodendron scandens pin cherry Prunus pensylvanica
hemp dogbane Apocynum cannabinum pink lady's-slipper Cypripedium acaule
horse-chestnut Aesculus hippocastanum poinsettia Euphorbia pulcherrima
horseradish Armoracia rusticana poison ivy Rhus radicans
hound's tongue Cynoglossum officinale poison suckleya Suckleya suckleyana
hydrangea Hydrangea macrophylla poison sumac Rhus vernix
Iceland poppy Papaver nudicaule poison-hemlock Conium maculatum
Indian mustard Brassica juncea pokeweed Phytolacca americana
Indian-tobacco Lobelia inflata ponderosa pine Pinus ponderosa
Jack-in-the-pulpit Arisaema triphyllum potato Solanum tuberosum
Japanese wisteria Wisteria floribunda precatory-pea Abrus precatorius
Japanese yew Taxus cuspidata prickly comfrey Symphytum asperum
Jerusalem-cherry Solanum pseudocapsicum prickly lettuce Lactuca scariola
jimsonweed Datura stramonium primula Primula obconica
Johnson grass Sorghum halepense prostrate pigweed Amaranthus blitoides
Kaffir lily Clivia miniata purple cockle Agrostemma githago
Kentucky coffeetree Gymnocladus dioicus purple locoweed Oxytropis lambertii
kochia Kochia scoparia radish Raphanus sativus
lamb's-quarters Chenopodium album rapeseed Brassica napus
large-leaved lupine Lupinus polyphyllus red chokecherry Prunus virginiana
leafy spurge Euphorbia esula red clover Trifolium pratense
leatherwood Dirca palustris red maple Acer rubrum
lily-of-the-valley Convallaria majalis red oak Quercus rubra
locoweed Oxytropis sericea redroot pigweed Amaranthus retroflexus
low larkspur Delphinium bicolor reed canarygrass Phalaris arundinacea
maidenhair tree Ginkgo biloba rhubarb Rheum rhaponticum
mango Mangifera indica Russian knapweed Centaurea repens
marijuana Cannabis sativa Saskatoon (a serviceberry) Amelanchier alnifolia
marsh arrow-grass Triglochin palustre scarlet pimpernel Anagallis arvensis
marsh horsetail Equisetum palustre seaside arrow-grass Triglochin maritima
May-apple Podophyllum peltatum sensitive fern Onoclea sensibilis
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COMMON NAME BOTANIC NAME COMMON NAME BOTANIC NAME
sheep sorrel Rumex acetosella white sweet-clover Melilotus alba
sheep-laurel Kalmia angustifolia wild cabbage Brassica oleracea
showy lady's-slipper Cypripedium reginae wild calla Calla palustris
showy milkweed Asclepias speciosa wild false indigo Baptisia leucantha
Siberian scilla Scilla siberica wild ginger Asarum canadense
silky lupine Lupinus sericeus wild indigo Baptisia tinctoria
silvery lupine Lupinus argenteus wild mustard Sinapis arvensis
skunk cabbage Symplocarpus foetidus wild onion Allium canadense
small lupine Lupinus pusillus wild parsnip Pastinaca sativa
smooth pigweed Amaranthus hybridus wild radish Raphanus raphanistrum
sneezeweed Helenium autumnale wormseed mustard Erysimum cheiranthoides
snowdrop Galanthus nivalis yellow iris Iris pseudacorus
Sorghum Sorghum bicolor yellow lady's-slipper Cypripedium calceolus
spatulate-leaved heliotrope Heliotropium curassavicum yellow rocket Barbarea vulgaris
spotted dumbcane Dieffenbachia maculata yellow sage Lantana camara
spotted water-hemlock Cicuta maculata yellow star-thistle Centaurea solstitialis
spreading dogbane Apocynum androsaemifolium yellow sweet-clover Melilotus officinalis
spurge-laurel Daphne laureola yellow toadflax Linaria vulgaris
squirrel-corn Dicentra canadensis
St. John's-wort Hypericum perforatum
star-of-Bethlehem Ornithogalum umbellatum
stinging nettle Urtica dioica
stinking rabbitbrush Chrysothamnus nauseosus
stinkweed Thlaspi arvense
Sudan grass Sorghum sudanense
sun spurge Euphorbia helioscopia
sunflower Helianthus annuus
sweet pea Lathyrus odoratus
Swiss-cheese plant Monstera deliciosa
tall larkspur Delphinium glaucum
tall manna grass Glyceria grandis
tansy Tanacetum vulgare
tansy ragwort Senecio jacobaea
Tartarian honeysuckle Lonicera tatarica
thin-leaved snowberry Symphoricarpos albus
timber milk-vetch Astragalus miser
tobacco Nicotiana tabacum
tree-of-heaven Ailanthus altissima
tulip Tulipa gesneriana
two-grooved milk-vetch Astragalus bisulcatus
veined dock Rumex venosus
velvety goldenrod Solidago mollis
Virginia creeper Parthenocissus quinquefolia
western bleedingheart Dicentra formosa
western minniebush Menziesia ferruginea
western poison-oak Rhus diversiloba
western water-hemlock Cicuta douglasii
white camas Zigadenus elegans
white clover Trifolium repens
white oak Quercus alba
white rose-bay Rhododendron albiflorum
white snakeroot Eupatorium rugosum
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