Also known as: Petunia x Hybrida

These brightly-colored flowers are popular in nearly every garden in North America – they're seen in containers on downtown streets, in park gardens and on front stoops. Whether you love them or hate them, petunias provide a splash of summer color in the hottest parts of the season. The South American native has been a component of every summer garden because it's easy to take care of and flowers all season. The name petunia is taken from the old French, "petun", meaning tobacco.

Petunias, heirloom plants that have been around in their current incarnation since at least the early 1700s, are part of the solanum family, which also includes nightshade, tomatoes, eggplant, mandrake and tobacco. In fact, the plant has calming properties that soothe nerves and reduce anxiety. Petunias were first seen in Europe around 1800 and have been a popular flower on both sides of the ocean ever since.

The flowers are best known for their bright, hot-colored blossoms that, when mass-planted, create an ocean of beauty. The blossoms can be pink, purple, red, white, yellow, or bicolored. In fact, because petunias are cheap and easy to grow, people may create themed gardens using the flowers' colors for a summer holiday or special occasion. The foliage is dark green and regular. The flower grows to a height of 18 inches and spreads out to 24 inches. Plant them out when the soil has warmed, and space them 18 inches apart.

Growing Petunias

Petunias need full sun and very little water to grow, which makes them a perfect plant when the summer gets hot and dry. Plant them in average, sandy soil that's very well-drained. It's a good idea to cut the plants back in midsummer to encourage new growth and flowers. Pluck the spent heads to keep the plant flowering. If you're propagating from petunia seed, push the seeds into the soil's surface, but don't cover them up. Beware – heavy rain will damage petunias.

Recommended Varieties

Petunia x hybrida has three categories: grandiflora, which have large flowers in a variety of colors and forms; multiflora, which have smaller, more profuse blooms; and milliflora, the newest category, which have flowers spread thoroughly over the whole plant. Of the three, grandiflora is the most likely to be damaged by rain. "Wave petunias" is one of the newest varieties that's sure to give you a riot of color this season.

Landscape Design Tips

As long as there's enough sun and little water, petunias will grow anywhere. They look especially pretty when planted in container gardens or in "waves" in the garden. Petunias make an excellent border plant.

Gardening Zones

Petunias are hardy in zones 3 to 11.

Problems and Pests

Fungi can be a problem for petunias, but is easily avoided through careful watering and well-drained soil. In terms of pest control problems, aphids can bother petunias as well.