Are Heleniums invasive?
Inula helenium (Elecampane) is listed in the Invasive Plant Atlas of the United States. According to the U.S Forest Service, Invasive species have contributed to the decline of 42% of U.S. endangered and threatened species, and for 18% of U.S. endangered or threatened species.
How tall does helenium get?
Newly-planted perennials usually flower the first year, but will take at least one full growing season to mature. In areas that get plenty of summer rainfall, heleniums may grow up to 4 feet tall and need to be staked. If your plants regularly grow taller than you’d like, pinch back the new growth in late spring.
What does helenium look like?
Helenium flowers look similar to coneflowers (Echinacea spp.) in that petals face outward from a central cone in a ray shape, or may droop downward. You can distinguish helenium from coneflowers by its late summer into early fall bloom time; in contrast to the early summer blooms of coneflower.
Is helenium drought resistant?
Abundant, multi-flowering helenium is hardy to Zone 3 and nearly drought-tolerant. Known by its common name, sneeze weed, this plant used to be harvested, dried and then made into a powder which some people then used as snuff to promote sneezing!
Do slugs eat Heleniums?
Young Heleniums are very tasty to slugs and snails but established plants are rarely affected. Either keep a watch out and manually remove the pests or put down slug pellets.
What to do with Heleniums after flowering?
Heleniums generally need staking to keep them upright, but to avoid this you can give them the ‘Chelsea chop’, in May, or cut them back to 30cm (12in) in mid-July. This delays flowering slightly but keeps plants more compact so you can enjoy the flowers on neat, unstaked plants.
How toxic is sneezeweed to livestock?
Eating about 1 kg of green sneezeweed leaves daily for 10 days may poison sheep. Some animals die within a few days after first signs appear. Others that develop a chronic form of poisoning may live for 2 to 3 weeks.
When should you plant Heleniums?
The best time to plant Heleniums is around the last week of March. The plants need to establish themselves well before winter so don’t plant them after the end of June. Harden the plants off for a week or two before planting them.
Are Heleniums Hardy?
Bringing warm colour to borders from mid-summer into autumn, these sun-loving perennials are tough, hardy and easy to grow. They combine particularly well with grasses and other late-flowering perennials in prairie-style plantings.