Late summer gardens shine with pieces of gold
Flowers blooming in golden yellow fill the garden in late summer. Maybe Mother Nature planned it that way to brighten shortening days. Or maybe it's summer's way of going out with a bang.
Either way, the garden will glitter with late summer gold if some of these sun-loving perennials are included in a landscape design.
The flowers of black-eyed Susan are a common sight in many landscapes. Rudbeckia Viette's Little Suzy is a compact cultivar that blooms from midsummer to fall, glowing at the front of perennial borders. This variety is less likely to suffer from Septoria leaf spot — a disease that commonly blackens the foliage of some other cultivars.
Other types of Rudbeckia are also strutting their stuff. The blooms of R. laciniata Herbstonne illuminate the back of a border. Its large, daisylike flowers top slender, branching stems.
The flowers of Rudbeckia maxima are nearing the conclusion of their season of bloom, but a few are still sitting atop giant stalks rising from huge powdery-blue basal foliage. Leave the stems with huge cones, remaining after the petals fall, standing for winter interest.
Another gold-flowering perennial for the back of large borders, moist meadows or wildflower plantings, Silphium perfoliatum is in its summer glory. It grows best in full sun but thrives in part shade in my garden. It is commonly called cup plant because the bases of leaves join together at the stem, forming cups that collect rain water.
If you cut back Coreopsis verticillata Zagreb after its first flush of sunny flowers in May and June, another round of beaming blooms is the reward in late summer and fall. Plants grow up to 18 inches tall and spread by rhizomes in a spot with full sun and well-drained soil.
Heliopsis helianthoides Tuscan Sun shows off its golden blooms in the middle of the border. False sunflowers are available in range of sizes, but this is a favorite for its flowers of bright yellow petals surrounding orange button centers on sturdy stems. Summer Sun grows a bit taller and features semi-double flowers. Both are beautiful as accents or planted in grand masses of sunshine. Sunstruck is a short variety — just 16 inches tall — with variegated foliage.
Helianthus Lemon Queen flaunts its sunny blooms high in the sky. Strong stems grow quickly up to 8 feet tall. Small, but plentiful, lemon yellow flowers bloom in July and August. Flora Pleno grows 4 to 6 feet tall and boasts double blooms.
When most of us think of coneflowers, we probably picture pink petals around large brown cones, but Echinacea Harvest Moon sports deep golden yellow petals around orange cones. Plants grow up to 30 inches tall. Butterflies love them as much as gardeners.
Goldenrods join the party of gold-flowering perennials later in summer. Solidago rugosa Fireworks grows at least 3 feet tall and explodes into golden flowery fireworks. Goldenrods do not cause hay fever, as they are sometimes mistakenly accused, so don't be afraid to plant these beauties for late summer color.
• Diana Stoll is a horticulturist, garden writer and speaker. She blogs at gardenwithdiana.com.