by Anna Harrison

Created on: January 14, 2009

Cosmos are one of those flowers that just about every gardener has grown at one time or another. An annual that is pretty simple to grow, they require little care, and can thrive in all kinds of conditions. The only thing that they do require is lots of room and they should be planted at the back of flower beds or borders. Varieties like "Sensation" can grow to over 5 feet and spread to over 2 feet across. By the end of the growing season most full grown cosmos will require staking, as they have a tendency to split just above ground level.

Like so many other annuals, cosmos love hot sunny conditions and dislike overly wet soil. Keeping them too wet will impair the growth of flowers and they may even rot. They will grow in partial shade, but will probably have more luxurious foliage and few flowers. All of the cosmos varieties make excellent cut flowers. The soft, delicate foliage is a great addition to flower arrangements as well, and will last for quite a while. They look wonderful with daisies or other wildflowers.

When attempting to grow cosmos from seed, do not sow too thickly as almost every seed is likely to germinate. They are that easy to start. Don't be afraid to start planting indoors in late winter. While easy to grow, they are slow to mature. Here in New York, they can be started around the end of March, to be set outdoors in the middle of May. Usually they do not bloom until the end of July. Once cosmos begin flowering though, there is no stopping them. Not until frost comes anyway. These prolific bloomers will provide nonstop flowers all fall if deadheaded regularly. Be sure to let some of the flowers go to seed to save for next year.

These days, there are so many varieties of cosmos that it is hard to know which ones to choose. Daydream cosmos are perhaps the prettiest, with dark pink in the center, fading to pale pink petals. Most varities of cosmos come in shades of pink and white. There are several yellow and red types, which are a little harder to grow, but gorgeous as well. "Seashell" cosmos have tubular petals and are quite unusual. Dwarf varieties look great when planted in front of the larger ones.

Bees, butterflies and hummingbirds love all varieties of cosmos, which only adds to their appeal. There are few annuals that provide such a show for such little effort. Unfortunately, deer also love them and will take advantage of every opportunity to feast on the flowers. If deer are a problem, planting as close to the house as possible will help to deter them.

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