There is a long history of Zinnias dating back even into the late 1700s. They originated in Mexico and over the years have been bred to produce many colors, sizes, and forms. The color range is vast with pink, rose, red, cherry, lavender, purple, orange, salmon, gold, yellow, white, cream or light green. There are small, dwarf forms that are great for containers or edging the front of the border, and there are tall forms, up to 36 inches that fill in the back of the border very nicely!
There are different flower forms:

1. simple, single petal layer with exposed center
2. semi-double have many rows of petals with an exposed center
3. dahlia type, usually semi-double, have large, flat blossoms
4. double-flowered have many rows of petals with no exposed center, and within this form there are beehive (small blooms with stack of petals), button type (small blooms but flat) and cactus type (twisted or bent petals with rolled edges).

Zinnias will perform the best in full sun and in fertile soil that drains well. The plants should be kept well-irrigated, and blooms will be in abundance with a few applications of fertilizer throughout the summer months. Remove the faded blossoms to encourage new blooms. Zinnia plants will bloom when very young and continue to produce blooms until fall frosts.
Starting Zinnia seeds directly in the flower bed in the spring once soil is warm is a great way to have a mass planting and a bold color effect. Pinch the tops when they are 4 to 6 inches in height to promote bushier growth. Space plants 4 to 24 inches apart depending on the variety. When growing Zinnias for cut flower production, crowd the plants slightly to encourage longer stems. The flowers are excellent for cutting and the bouquets can last a week or more in the vase.
These sun-loving, popular annuals are easy to grow, versatile, and a widely adaptable. Zinnia seeds are fairly large and easy to germinate. They are considered a good flower seed for children or beginner gardeners to use.