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by Pernell Gerver

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"The Best Summer-Blooming Perennials for Shade"

Summer is in full swing right now and the perennial garden is bursting with color. While the spring-blooming perennials are just a memory, it's time for the summer-blooming perennials to take center stage. There are lots of summer-blooming perennials for shade that span the entire season from early summer to early autumn and many are my favorites. Click on a plant name to order it from Pernell Gerver's Online Store.

Geranium cinereum 'Ballerina'Late spring and early summer is the season for hardy perennial geraniums. Hardy perennial geraniums form a handsome mound of foliage that ranges in size from a compact clump under six inches high and wide to nearly three feet high and wide, depending on species. All have palm-shaped, or palmate, leaves. Some are more deeply divided than others and the leaf color varies from light green to blue gray, to deep green. Many also have attractive fall foliage and even when they are not in bloom they are attractive in the garden. The flowers of hardy perennial geraniums are single and made up of five petals that overlap each other, giving them a rounded appearance. Flower color includes magenta, rose, pink, violet, lilac, blue, purple, and dark purple. Some species have attractive veining on the petals and others have a dark-black center that contrasts nicely with the flower. They grow well in shady spots in the garden.

Astilbe is a popular shade-loving perennial. There are many different types of astilbes that offer a bloom period from late spring to fall. They are versatile perennials that form handsome clumps in the garden. They grow well in part sun to deep shade, are available in a range of plant sizes from six inches tall to four feet tall, and have an extensive range of flower colors including white, red, purple, lilac, lavender, rose, salmon, and pink. Even after the flowers have faded, the seed heads remain attractive in the garden. I don't cut them down in fall, but leave them to provide winter interest. They are especially attractive after a light dusting of snow. The foliage of astilbes is attractive all season long. It's finely cut and ranges from bright green to deep bronze, depending on variety. The foliage is glossy on some types. The thunbergia species of astilbe is the largest of the astibles with flower stems that can reach 40 inches high. It forms large, impressive clumps and its flower plumes stand high above the foliage. The foliage is generally medium green and finely divided. One of the most striking varieties is 'Ostrich Plume.' Instead of upright plumes, it bears graceful, arching flowers. The flowers are deep-rosy-pink in bud that open pale pink. It begins blooming in midsummer and is in bloom for weeks. The seed heads remain attractive well into winter on this attractive astilbe.

One of the best summer-blooming perennials for shade is Ligularia 'The Rocket.' It grows in the deepest, darkest shade there is. In my own garden, it's growing on the north side of my potting shed under the shade of tall trees. It never sees sun, but it's thriving and blooming. It forms a two-foot-wide mound of interesting, triangular leaves. The leaves have deeply-serrated edges, giving them a prehistoric look. In summer, five-foot-tall deep purple flower stems rise through the foliage and bear bright-yellow flowers.

Japanese anemone is a late-summer-to-autumn-blooming perennial that thrives in the shade. One of my favorites is the variety 'Pamina.' It forms a handsome mound of foliage not quite two feet tall - no staking required! Flower stems rise through the foliage and stand three feet high. Dozens and dozens of flowers bloom over a long period from early September right through frost. The double flowers have many petals surrounding a central cluster of orange stamens. Flower color is rosy lavender.

Pernell Gerver's Gardening Q & Aby Pernell Gerver

"Hemlock Woolly Adelgid a Serious Pest"

Q. I have a 10-foot-high hedge of hemlock. Many of the branches have white milky spots on them (looks like little eggs). Can you tell me what I can do to preserve the hemlocks? Thanks.

A. The condition you are describing on your hemlocks sounds like hemlock woolly adelgid, a serious pest of hemlock that can kill an entire tree in a few years. In recent years this pest has reached epidemic proportions throughout western Massachusetts. When you notice the white cottony masses on the needles on the branches you need to act quickly. I have successfully controlled hemlock woolly adelgid on my hemlocks by spraying Neem Oil on the hemlocks in early April through June to control the first generation. The second generation hatches in July and feeds into fall. In September through October the females produce the cottony wax in which they will lay eggs early the following spring. I have had good success controlling this serious pest of hemlock, but because of the speed with which it can kill the plants and the numbers of pests that have moved into the area, I plan to treat for it often and every year.

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