Because clay causes soil to drain slowly, it can be hard to grow perennial flowers in clay soils. Perennials have a shallow root system and need the type of environment that can flourish year after year. That's why clay soil isn't an ideal choice for most perennials, although there are some perennials that do better than others such as certain daisies, black-eyed Susans and others.
Echinacea Purple Coneflowers
Echinacea purple coneflowers are perennials that break up soil as they grow. These plants love sunny spots are and can tolerate drought-like conditions, besides clay soil, making them a popular perennial. Although flowers, they're also considered as herbs. They have many cultivars that have a wide range of colors and petals, in addition to other features.
Black-eyed Susans, also known as Rudbeckia, are hardy clay tolerant perennials that are low maintenance as they love sunshine and are forgiving when neglected. this flower is one of the most common American wildflowers known. Their blooms are golden or yellow-orange with russet petals and black-brown or green centers. These bright looking plants that stands stiff and erect look stunning when purple coneflowers are placed in back of them.
There are a few species of daisies that are able to grow in clay soil. Leucanthemum Maximum Shasta daisies do well in a clay soil, although they live longer in well drained soils. They're white daisies originating from the mum family, providing cherry blooms that resemble mums. Painted daisies, which are similar to coneflowers, can also survive in clay soil. They come in various colors, as their name suggests.
Hostas or plantain lilies are good perennial flowers for clay soils. These perennial plants, native to Asia, produce flowers, although they're not known for their flowers, which bloom from late summer to early fall. They come in colors of white, green, yellow and blue-green. Although they can grow in clay soil, their soil must have good drainage.
Other Clay Tolerate Perennial Flowers
Coreopsis, also known as tickseed, is a plant that's drought resistant, besides clay tolerant. In fact, it's considered one of the best perennial flowers for clay soils. The Coreopsis is an excellent cut flower that also attracts butterflies. This plant produces masses of small flowers that resemble daisies during summer. It has the longest blooming period of any perennial, besides being tough. According to the Doug Green Garden website, the best Coreopsis species to grow in clay soil is Coreopsis Verticillata, which produces yellow flowers in open, loose clusters on wiry, thin stems. Roughly 80 Coreopsis species are native to North and South America.