The essential difference between annuals and perennials is that annuals are one-season plants, completing their life cycle with the first killing frost, whereas perennials live through multiple growing seasons. Examples of common annuals include impatiens, pansies and petunias, while some favorite perennials include butterfly bushes, daisies and hostas.
Annuals are labor-intensive and require more fertilizing, weeding, deheading and watering than perennials. Annuals are best used as colorful filler in established gardens and can be easily grown in containers and hanging planters. Soil preparation is more critical for perennials, and be sure to choose plants that are well-suited regarding sun/shade balance to the planting site.
Pros & Cons
Annuals are more expensive than perennials over time because they need to be replaced every year; however, with proper care, annuals provide season-long blooms. Perennials are better choices for gardeners who prefer lower-maintenance gardens because once planted, their care is minimal. Depending on climate, some annuals function as perennials in frost-free areas, and some perennials are classified as annuals in warmer areas because of longer growing seasons.