6/9
Quaking Aspen
As a member of the poplar family, quaking aspen (Populus tremuloides) is indeed a fast-growing tree for your yard, adding 2 feet or more of height annually. It tops out at 40 to 50 feet but tends to send up new shoots from its roots to eventually form colonies. That’s fitting because with greenish white to cream bark and golden yellow fall foliage, aspen looks really good in clumps or groves. Incidentally, the popular names, quaking aspen and trembling aspen, refer to the leaves quaking or trembling in the slightest breeze, providing a pleasant sound with a psychologically cooling effect. Zones 2–6.
7/9
Smoketree
Smoketree (Cotinus coggygria) is a multi-stemmed small tree that gets its name from the large, airy flower clusters that appear in midsummer and look like puffs of smoke. Growing 10 to 15 feet tall, smoketree also boasts attractive foliage. And it fills out a landscape beautifully. There are a number of popular cultivars including ‘Royal Purple’, with purple foliage turning scarlet in fall, and Golden Spirit, featuring chartreuse foliage that takes on orange and red hues in fall. Zones 5–8.
8/9
Spider Flower
Spider flower (Cleome hassleriana) is an old-time favorite that grows quickly from seed and can reach six feet tall. (Smaller cultivars are only 18 to 24 inches.) Once in the garden, this self-seeding annual will come back again and again, although future generations may have flowers of a different hue than the mother plant. The spiderlike flowers make your garden pop with pink, rose, purple and white. Plant spider flower in groups to give quick cover that flowers from early summer until frost.
