Perennial plants are ideal for the gardener who want to avoid planting new flowers each year. Perennials are used to fill flower beds, edge walkways, provide screening and add color and fragrance to the yard. When designing a garden, a plant's height and flower color must be considered when deciding its location in a border.
The armeria, or sea pink, blooms from late spring through mid-summer with globe shaped flower clusters in lilac, white, red or pink. The 1-inch flowers each set atop a stem that is 1 to 1 ½ foot long. It makes a good choice for along the front of a border. The plant requires plenty of sunshine, good drainage and prefers a dry, under-fertilized soil. Flower production can be diminished by over-watering. It is also a good choice for planting in a rock garden.
Another good selection for the front of a border is the bergenia. It has a large, broad, leaves and delicate flower clusters in shades of pink and white. In many areas, the plants stay green all year, and in cold regions, it turns bronze during the fall. It can be planted in full sun, but prefers light shade if planted in extremely hot climates. If planted along a pond, it will grow rapidly.
The cassia or wild senna is suitable for planting along the backs of borders. It will grow up to 7-foot tall and has 1 to 3-inch flower clusters of brilliant yellow blossoms. The leaves are fern-like and are normally between 6 to 10-inches long. It will grow in full sun or partial shade and prefers a well draining soil. When planting, space the cassia about 2-feet apart.
Tolerant of salt spray, the sea lavender is a good choice for sea-side planting, as well as a border plant. When planting, it should be spaced about 1 ½ to 2-feet apart, in well-draining soil. If planted from seeds, it will take several years before it comes to full flowering. The sea lavender cuttings also make an excellent cut flower and suitable for drying. To dry, bundle the cuttings and hang upside down in a well ventilated, dry area.