Are Pink Cosmos Perennials?
When there are approximately 25 species of cosmos, just among these commonly grown varieties creates pink blooms. With their daisylike flowers which grow in shades from delicate shell pink to vibrant fuchsia, pink cosmos (Cosmos bipinnatus) are cheap plants which provide reliable summer color in a assortment of sizes and forms. You may discover once-and-done annuals or the ones that return for another season of perennial-like blossom, based upon your gardening habits.
Cosmos Bipinnatus Culture
Plant pink cosmos from seedlings available at nurseries in the spring. You may also start them from seed indoors four to six weeks ahead of your area’s last frost or in a full-sun place in the garden in mid- or late spring when soil is 65 degrees Fahrenheit or warmer. The plants aren’t particular about soil and actually grow better — more upright and stocky — in average to poor soil. They don’t need fertilizer, and applying it may delay blossom. Once established, these Mexican natives simply need extra water in circumstances of intense drought.
Annual or Perennial
Most varieties of cosmos are warm-weather annuals — growing from spring until they’re stopped by frost in the autumn. In frost-free locations, but the plant may keep blooming as long as you keep it from setting seed. Once an annual creates seed, the plant completes its life cycle and shouted back. Perennial plants undergo several flower-to-seed cycles — coming up from the very same roots — before dying back. Biennials are somewhere in between — sprouting and leafing out in their first year and flowering, setting seed and then dying in their next season. 1 perennial genus of cosmos, chocolate cosmos (C. atrosanguineus), grows from a rhizomatous root in U.S. Department of Agriculture plant hardiness zones 7 through 11, but it creates a deep red-brown, nearly black flower.
Pruning and Reseeding
Pruning, pinching or otherwise deadheading your pink cosmos to stop them from setting seed is a double-edged sword. You will keep current plants blooming but stop them from falling upon the seed that results in fresh plants for next season. Strike a happy medium by pinching out the initial flush of bloom, pruning back after the second round to 12 to 18 inches, while permitting late-season flowers put and dump seed. This causes the new springtime plants which often lead gardeners to error cosmos for perennials.
Pink garden cosmos come in a assortment of C. bipinnatus cultivars, from the ones that create 4-foot plants for the rear of the edge — such as “Sensation,” with flowers 4 to 6 inches across in shades from white through red — to “Sonata” with pink, pink and red flowers on plants just 1 foot tall. Other pink cultivars include “Seashell,” with rolled, tube-shaped petals; “Daydream,” using light pink petals that darken toward the yellow center; “Psyche Mix,” with dark pink to burgundy outer petals and a second layer of small, frilly petals in mild pink close to the center; and “Piccotee,” which flowers with white flowers which have pinkish red edges and therefore are pinstriped with crimson to give them a pink impact.