Planting with Perennials
Gardeners who work almost exclusively with perennial plants will often have no shortage of praise for the merits of these multi-year landscape plant selections, but for the new gardener, vegetable gardener, annual gardener, or more arboriculturally-inclined gardener, the utility of these plants isn’t always fully appreciated.
Technically-speaking, perennials are native or non-native plant selections that have a life cycle that endures for a period of three years and beyond. One year landscape plants are of course “annuals”, and two-year landscape plants are called "biennials"; the latter usually flower in their second summer of life, produce seeds, and then die back. However, some plants that are called “biennials” are more properly “short-lived perennials”, as processes like deadheading, or even the growth of lateral offsets from the mother plant can give them a multi-year clump-forming habit. Suffice it to say the boundaries of what constitutes a “perennial” plant are not rigid, but they imply a greater sense of permanence than other choices.
Perennial gardens are beneficial to virtually any landscape for a variety of reasons.
- They provide longer-term ecosystem services. Beneficial insects like pollinators are creatures of habit, and will grow their populations around sustainable and uninterrupted sources of forage (food). A flowering perennial garden with bloom times staggered over the growing season is a consistent source of food, and therefore a refuge for important co-tenants in our habitats.
- These ecosystem services provided by perennial plants add value to other garden projects. Vegetable gardens bordered by perennials are more likely to be pollinated, as are fruit trees and shrubs.
- Owing to their adaptiveness to the local climate, perennials are usually more efficient in the landscape, requiring far less labor and far fewer inputs—such as water or fertilizer—than annual plants. With careful plant selection, a perennial bed can cover a hot and dry spot without any need for watering, or can be planted in low moist areas where storm water collects, to help clean it as it infiltrates the water table.
Wherever or whatever you are planting, a little bit of research into your local habitat, combined with good planning and plant selection can go a long ways toward creating perennial combinations that work for your space and needs.