View a jaw-dropping garden and it's likely you're seeing the potential of perennials at work. Trees and shrubs form the bones, and annuals add bright notes to a garden, but it's perennials—herbaceous, nonwoody plants that go dormant in fall, then return in spring—that provide the textures, forms, and calculated sequence of colorful bloom that every garden needs. Once planted, a perennial garden can endure for years, even decades. That's why selecting them is such an important process, one that can be challenging given the myriad new species and cultivars made available every year.
To come up with a group of perennials that could be considered the backbone of any well-planned garden, we turned to horticulturists Ruth Rogers Clausen and Thomas Christopher, authors of more than a dozen books between them, including their new guide, Essential Perennials (Timber Press). They gave us a short list of plants that deliver successive bloom—early, mid, and late season—and grow well in most parts of the country with minimal care (See our US Plant Hardiness Zone Map to see what works best for your region). For new gardeners, these tried-and-true picks are a great place to start; experienced gardeners on the hunt for exceptional cultivars will find those, too. Read on to see their favorite colorful perennials.
Shown: Riotous with high-summer color, this perennial border is built to last. After the delphiniums fade, purple salvias and strappy-leafed variegated irises keep the show going till fall.