For brilliant colour in the hottest, sunniest part of the garden, zinnias are ideal.
Zinnias are available in almost every shade except the blues, and in a range of sizes from tiny dwarf plants with charming miniature flowers to large plants with ruffled and curly petals (yes, the hybridists have been very busy, much to the advantage of this popular flower).
Zinnias are best used in massed garden displays. Dwarf forms grow to 20cm in height while large forms can reach 70cm or more. They prefer full sun with protection from very strong wind. They are best grown in warm or tropical areas but may not do well at the coast as they are prone to mildew in humid or damp environments.
For sowing and growing tips visit my website http://gardeningisezee.com. Check out the Annuals category for a whole lot of information about zinnias.