Using perennials in your garden Perennials are favoured by many gardeners, not only for their ability to bloom for several seasons, but for the wide variety of colours, shapes and sizes they come in as well. Whereas annuals must be planted anew every season, perennials can be left in the ground to bloom for several seasons. This makes gardening with perennials less costly and means that the perennial garden can be easier to maintain. In addition, most perennials are very easy to work with, and the demands they place on their gardeners are usually quite low. Sufficient water, good soil and abundant sunshine are all most perennials need to provide beautiful blooms all season longs. There are several important considerations with perennials, however, given the nature of their growth. Since perennials remain in the ground year after year instead of being started fresh every season, they are more prone to diseas...