Cosmos are popular garden blooms in the daisy and sunflower family. The plants are native to Mexico, but have become a common sight in gardens across North America. Cosmos must be planted annually outside their native environment. They are especially favored by those who wish to attract butterflies to their yards. When it comes to appearance, cosmos have similar flowers to other members of the daisy family. They usually have eight flowers ranging in color from pink or white to purple, though there are also other shades, especially in hybrid varieties. Cosmos thrive in full sun, though they can survive in partial shade. They prefer alkaline soil with a pH above 7.0, and need consistent temperatures of 75ºF for seeds to germinate. At full growth, cosmos plants can reach sizes of up to six feet tall and three feet across. Because the bright flowers are good at attracting butterflies, birds, and other pollinators, they are popular companion plants in fruit and vegetable gardens. The pollinators that visit cosmos will likely stop at plants nearby, too. Many people plan out their gardens months in advance. They select just the right plants that will provide beauty and utility at the same time. Cosmos are a wonderful choice and will bring a splash of color through their flowers and the butterflies visiting them.