by Ray AllenYou've planted your tomatoes and peppers and set out your petunias and geraniums. Whew! If you’re like most gardeners, you rush to do all your planting in spring, and then switch gears to "maintenance mode." Yes, spring is the time to plant most vegetables and annual flowers, but when it comes to planting perennials you can take a more leisurely approach. You can plant them all summer long, even into autumn. When you plant perennials, you’re taking the long view. Many perennials will produce some flowers the first year, but they really come into their own in subsequent seasons. So now that your spring planting season is over, it’s time to stroll your ornamental beds knowing that there's still time to plant. Do you have a shady corner that needs some livening up? A few astilbes, bleeding hearts, ferns, heucheras, hostas, and/or hellebores might be just the ticket. Full sun? You have dozens of plant choices, from asters and bee balm to veronica and yarrow. While you're pondering what to plant, keep in mind each plant’s bloom time. Most perennials bloom at their peak for a few weeks to a month or more. For example, hellebores bloom in early spring, coreopsis in summer, and asters in autumn. Choosing plants with a variety of bloom times ensures you'll have something flowering all season long. Because the weather in summer is hotter and often drier than in spring, you’ll want to pay a little extra attention to summer-planted perennials to make sure they get off to a good start. Providing adequate water is most important. New plants have confined root systems so they'll need frequent watering. Once the roots expand into the surrounding soil they’ll be better able to withstand occasional dry spells. During hot, sunny spells check new plants daily and water as necessary to keep soil moist. Windy weather also has a drying effect. If you planted lots of annual flowers this spring, consider replacing some of them with perennials. You'll save yourself the work (and expense) of replacing plants each spring, and you can enjoy how the garden changes throughout the growing season as different perennials come into peak bloom.