Gardening in our Zone 6b is both a blessing and a curse, but I’ll bet that gardeners in different gardening zones say the same thing. My wish list of the things I’d like to grow but cannot in my climate begins with ceanothus, and then continues on to aubrieta, agapanthus, camellias, crape myrtle, bougainvillea, and on, and on….
That said, I’m grateful for what I’ve got and the following is a list of my top ten favorite perennials for sunny borders. These are proven garden workhorses and my selection is based on performance, long-blooming period, beauty and their ability to do double duty, either by flashing fancy foliage or their ability to behave nicely, play well with others and suppress weeds as a ground cover. My list won’t include plants that need coddling (the subject of another post) or new, patented cultivars that aim to achieve ‘ Perennial Plant of the Year’ status, although some of them may have been at one time. The list below is based on my experience on how these plants perform in our New England climate. Here’s my list of proven winners:
Nepeta:(Catmint) This is a plant that makes you look like you know what you’re doing. The generous, soft grey-green foliage, combined with its robust, dome-shaped growth habit, provides structure in the garden and its diaphanous haze of cascading lavender-blue flowers creates instant romance. A pairing with Lady’s Mantle produces an effect so beautiful as to defy description.Alchemilla Mollis: (Lady’s Mantle)I have a passion for this plant that verges on a mania. Now, I know plenty of gardeners who feel that chartreuse has no place in their gardens, but I beg them to reconsider this one. The foliage is a soft, grey-green with a poetic and beautiful way of unfolding, like a japanese fan, and catching, within its folded concavity, dewdrops that shimmer like diamonds. The flowers, in robust clusters of tiny sprays, are a vivid, acid green/chartreuse, and enliven and brighten smokier, hazier companions in the same way that vinegar or lemon juice do to salads and sauces. Cut the flower heads back and you may get a second display later in the season. (BTW, this advice applies equally to Nepeta).
Geranium ‘Rozanne’: (Cranesbill) , Here, I’m talking about the perennial ‘Cranesbill’, not the ubiquitous container garden annual, Pelargonium, wrongfully called by nurseries, supermarkets and consumers, “Geranium”. ( Please; people- let’s get it together with the &%@#*!# taxonomic nomenclature. When I’m designing a garden for a client and I suggest some geraniums they think I’m talking about annuals. If I say Cranesbill, they ask, “Oh, what’s that?, and here we go again, caught in the vicious cycle). Unruly nomenclature aside, this staple of the perennial garden has a mounding, meandering and draping habit with beautiful foliage and presents a tremendous display of violet-blue flowers, in astonishing abundance, from June till frost.
Iris siberica: (Siberian Iris) Nothing announces late spring-early summer like Siberian Irises. Erect, floriferous, strident; it makes a statement that we all want to hear, whether it flowers white, buttercream, blue, inky violet…it is always beautiful. After the flowers have faded, its sword-leaved foliage contributes height and texture to the garden. There are some variegated cultivars available and these can create an artistic accent in an otherwise predominantly green-foliated garden.
Leucanthemum:(Shasta Daisies) There are plenty of folks, including my horticulturally sensitive husband, who consider these plants to be common; as common as mud. Phooey! I ask you, what’s common about a robust stand of gleaming white, crisp, fresh, erect, structural Shasta daisies? Everything and nothing! ( You will have to deadhead them to maintain their fresh appeal, but its a small price to pay, and a nice activity at the end of the day with a glass of wine in one hand and a pair of snippers in the other). A nice,big, drift of Shasta daisies in the right place, never offended anyone!
Coreopsis: (Tickseed) This plant has a presence by its striking and large clumps of golden flowers. It’s always a cheerful addition but, if you feel that it’s a bit too cheery, there are newer cultivars that offer more subtle shades of cream and butter-yellow. These newer versions blend well with the more refined constituents in your garden.
Paeonia: (Peonies) The argument continues over whether it’s the rose or the peony that is Queen of the Garden, and I’m not going there. Peonies need full sun and must be planted at the right depth to perform well, other than that, they’re relatively carefree. With such a dazzling array of colors and flower forms I’m always surprised that retail nurseries only carry half a dozen cultivars, usually white, pale pink or dark pink or red in the bomb shaped flower type. I encourage people to explore some of the more unusual single flowering types in colors that include coral, magenta and yellow. Peonies can be planted as a hedge, and in the right place, this can be quite stunning, albeit for a brief bloom period, but I think they perform best in the landscape when planted amongst later flowering perennials, like roses, daisies and geraniums.
Lavandula angustifolia: (Lavender)Elegant, fragrant, classic. It’s wands of pale lavender to deep violet create a beautiful vertical element in contrast to its blue-grey foliage. Not all types are hardy in our gardening zone. We have the greatest success with the cultivar ‘Munstead’. This plant thrives in poor, dry soil in full, baking sun. If you can’t provide these conditions try salvia nemerosa as an alternative.
Dianthus: (Pinks) This is another plant that drapes and cascades, and so looks particularly well when planted near the edge of the border or, better still, at the edge of a retaining wall, where it’s matt forming foliage will drape while its numerous flower stems will arch upwards. Its pale, blue-grey foliage contrasts nicely with Lady’s Mantle and Geraniums. My favorite is Bath’s Pink, a light, clear pink shade that is easy to combine with other colors, but I have trouble finding it in nurseries. Other colors are in shades of hot pink, magenta, red and bi-colors. We start ours from seed in the greenhouse so we can select the colors we want.
Artemesia: (Wormwood) The soft, silver foliage of this plant is invaluable in the garden for creating contrast. ‘Silvermound’, as its name implies, produces domed hummocks of silvery grey, which, when dotted throughout the border, creating a pleasing rhythm of shape and color.