Perennial Plants Definition


Year after year, gardeners can count on their perennial plants emerging from their roots and growing into full form during the growing season. According to, plants are classified as perennials if they have a life cycle that extends beyond two years. Many perennial plants live for many years from the same established root system.


To avoid having to transplant annuals to the garden every year, homeowners and landscape designers incorporate perennial plants into their gardens for perpetual shows of flowers and foliage each year. Some low-growing perennials work well as groundcovers and landscape edging, while taller perennials add height and body to the landscape and garden design. A mixture of perennials not only adds visual interest when arranged by height and spread, they also make for a low- to no-maintenance garden--more enjoyment and less work.

Flowering and Foliage Perennials

These perennials are the mainstay of most landscapes and gardens. They are prized for the dramatic beauty of their leaves and the varying colors of their blossoms. This is a broad category of perennials that includes specimens of different heights with varying soil and sun requirements. The flowering and foliage perennials include plaintain lily (Hosta spp.), New Zealand flax (Phormium spp.), foamflower (Tiarella spp.), periwinkle (Vinca spp.), wild ginger (Asarum spp.) and corabells (Heuchera spp.).

Perennial Ornamental Grasses

Ornamental grasses provide year-round form and coverage. They add height, body and interest and can be arranged as a natural fence and screen to section off areas of your garden. When you need to fill up a void or add plantings to an otherwise bare area, ornamental grasses may be a maintenance-free answer. There are several types of ornamental grasses--some are low-growing and others tower over 5 feet. Some ornamental grasses require full sun and some can thrive in partial shade. Blue oat grass (Helictotrichon spp.), Moor grass (Molinia spp.), fountain grass ((Pennisetum orientale), Japanese blood grass (Imperata cylindrica) and ribbon grass (Pharlaris arundinacea) are a few common ornamental perennial grasses.

Perennial Herbs

Incorporating perennial herbs in your garden is a convenient solution to keeping fresh culinary and medicinal herbs at your disposal and on demand. Some common perennial herbs for a home garden include sage (Salvia officinalis), mints (Mentha spp.), lavender (Lavandula officinalis), thyme (Thymus vulgaris), chives (Allium schoenoprasum) and rosemary (Rosmarinus officinalis).


Perennials depend on the quality of their soil, moisture and lighting requirements. When planning the arrangement of your perennial garden, group companion plants together that do not compete for the same soil nutrients but require the same type of lighting and moisture requirements. Careful planning of your perennial garden will ensure healthy plant development for years.

Keywords: perennial plants, planting perennials, perennial garden

About this Author

Naima Manal's articles on health, diet, nutrition, alternative medicine, education, parenting, crafts, travel, home and garden and home improvement have appeared on eHow, Garden Guides, Trails, ConnectED, Helium and others. Manal received her B.S. degree in biology/pre-medical studies from Molloy College in 1994 and has been a freelance writer, teacher and homeschooling mom since 1993.