Creating a colorful garden in clay, sandy soils that are starved of nutrients is possible. In fact, many perennial flowers thrive in harsh conditions like drought and high humidity but without sacrificing their colorful, vibrant blooms. Flowers that do well in dry, poor soils are often drought- and humidity-tolerant--a good indicator that the plant is able to withstand nutrient-poor conditions.
Purple coneflowers (Echinacea purpurea) are a perennial flower with a moderate growth rate and clump-like form. Drought-, heat- and humidity-tolerant, purple coneflowers thrive in poor, dry soils. Purple coneflowers grow 3 to 6 feet in height and 1 to 3 feet wide, ideal for lining a flower bed.
Low-maintenance, purple coneflowers have pink and purple blooms that emerge in late summer and grow 6 inches wide. Blooming through fall, the lance-shaped leaves are bright green to and oblong. Purple coneflowers attract butterflies and bumblebees to the garden and prefer full sun and well-drained soils to thrive. To promote flowering, cut back or deadhead spent blooms as soon as they are visible. The USDA hardiness zone for planting is 3 to 9.
Lance-leaved coreopsis (Coreopsis lanceolata) is a fast-growing perennial bloom that grows in clumps ranging from 1 to 3 feet tall and wide. Drought-tolerant, coreopsis flowers grow well in a wide range of soil types, including poor, dry soil. The summer-blooming yellow flowerheads on lance-leaved coreopsis have a toothed edging and make striking, long-lasting fresh cut flowers. Heat- and humidity-tolerant, lance-leaved coreopsis blooms are ideal grown in arid climates where moisture is limited.
Lance-leaved coreopsis flowers require full sun to partial shade. Divide the coreopsis in early spring to plant in other areas of the garden like a perennial bed or meadow garden. Deadhead, or remove spent blooms on the lance-leaved coreopsis to promote new growth. The zone for planting is 4 to 9.
Goldenrod (Solidago nemoralis) is extremely tolerant of poor soils, including both sandy and clay varieties. Goldenrod grows in a clump-like forms that reach 1 to 3 feet high and wide. The gray-green foliage holds the yellow flower plumes that often attract butterflies to the garden. Goldenrod flowers bloom in fall to last through winter, making for long-lasting bloom.
Deer-, drought- and frost-tolerant, goldenrod is a hard perennial flower to grow in a dry rock garden for a bright burst of color. Goldenrod prefers full sun to partial shade and well-drained soils. Prolific at self-seeding, goldenrod can be divided in spring or fall to spread throughout the landscape. The zone for planting is 2 to 9.