Gorgeous lilac clusters atop long airy stems that reach 1 metre or more. V. bonariensis is heat and drought tolerant and blooms from July until frost. If there is a bee in the vicinity, it will be on this flower! It is the perfect plant for splashes of mid-border colour. This tender perennial is supposed to be hardy in zones 7 through 10 but we find that it overwinters in our zone 5 garden as long as there is snow cover. Even if your plants succumb, they will deposit their progeny quite liberally through your garden, but seedlings are easy to identify and pull, if you have the heart.
Hardiness zone: 7-10
Bloom type: Tender perennial. Often grown as an annual in zones 4-6.
Start indoors (recommended) 6-8 weeks before frost or seed directly once soil warms in spring. Sprinkle seed on soil surface and cover very lightly. Seed is slow to germinate and does not like too much water. Keep on the dry side until seedlings are up. Transplant outside into full sun when there is no danger of frost. Mulch lightly for winter protection.