Toadflax is a perennial that can carry harmful plant diseases while suppressing natural vegetation.
photo: Utah State University Archive
What you can do to stop the spread of toadflax
- Avoid planting toadflax and avoid wildflower seed mixes as they might contain this harmful plant. Seedling toadflax plants are weak competitors, so maintaining a healthy garden and/or mulching between plants will inhibit Toadflax seedlings.
- Toadflax can easily re-sprout from roots, so mechanical removal of plants (i.e. hand pulling, cutting, tilling) will likely need to be repeated for several years.
- Cutting plants or mowing large patches during the early flowering stage will prevent seeding, but will only stress (not kill) plants.
- Chemicals applied to toadflax may have limited impact, since the waxy texture of leaves and stems may prevent uptake of herbicide.
photo: Linda Wilson, University of Idaho
What is toadflax?
Plant Type: perennial
Size: up to 1.5m tall, single stem or bushy
Leaves: waxy, alternate along stem, heart shaped (L. dalmatica) or blade-like (L. vulgaris)
Flowers: Showy yellow snapdragon flowers with a spur on flower spikes, blooms May – June
Toadflax plants spread through both seed production and creeping roots - Roots penetrate up to 2 metres in soil and can spread 3 metres horizontally. Toadflax can harbour plant diseases and rapidly chokes out natural plant communities.
Toadflax is also known as Linaria dalmatica: Dalmatian Toadflax, Broadleaf Toadflax, Smooth Toadflax, Wild Snapdragon, Yellow Toadflax, Butter-and-eggs, Linaria spp. (Linaria dalmatica, Linaria vulgaris)
Consider some of these garden selections as alternatives to the toadflax
- Fine-leaved goldenrod (Solidago graminifolia)
- Goldenrod (Solidago canadensis)
- Annual snapdragon (Antirrhinum majus)
- Dwarf snapdragons (Chaenorrhimun minus)
- Mountain goldenbanner (Thermopsis montana)
Learn more about The City's initiatives to prevent invasive plant infestations.
Alberta Invasive Plants Council factsheets: