Divide and Replant Iris
The tall bearded iris, often called German iris, thrive on being divided and replanted at least every three years into newly reconditioned soil. The best time to do this is about four to six weeks after blooming, as the plants are entering a period of partial dormancy before gearing up again in late summer and fall. Cut leaves back to about 8 inches, dig up the clump, and break apart the rhizomes, keeping the newest and healthiest ones. Let the rhizomes air dry several days before replanting and watering in thoroughly.
Maximize Self-Sowing Annuals
The cottage-garden look can be encouraged by removing the seed pods of self-sowing annuals as they ripen and sprinkling them where you'd like some volunteers to grow. Seeds sown this year will grow and bloom next year. Just remember that you can't use pre-emergent herbicides where you sow seeds. Some of the annuals to consider include love-in-a-mist (Nigella damascena), spider flower (cleome), forget-me-nots (Myosotis sylvatica), cosmos (Cosmos bipinnatus), pot marigolds (Calendula officinalis), flowering tobacco (Nicotiana alata).
Watch for Plant Sales
Container-grown and balled-and-burlapped trees, shrubs, and perennials can be planted throughout the growing season, but as hot weather approaches, garden centers often have sales to encourage customers to come in once the spring rush is over. The key to having success when planting now is to remember to keep the plants well watered all summer. Try to plant just before rain is expected or on cloudy, cooler days. Don't waste your money on plants that haven't been well tended.
Don't Give Up on Planting Vegetables
In many parts of our region, spring has been a bit odd, with May being cold and damp, then the weather turning very hot. If you find yourself a bit behind in getting the vegetable garden planted, don't despair. Many summer crops, including ones best started from direct sowing, such as beans, summer squash, okra, chard, and beets, as well as tomato, pepper, and eggplant transplants, can be planted up through early July. Just be sure to water the seeds in well. Don't panic if transplants wilt; just water them well and put a cardboard box over them during the day, removing it at night, until they get established.
Some flowers have a tendency to flop, including fall-blooming sedums, delphiniums, tricyrtis, and lilies. Providing some type of staking helps to prevent this. Lots of different staking paraphernalia is available at garden centers or by mail order. One of the handiest is the circle with criss-crossing rods. For lilies, try staking each one with an individual stake. You can make homemade supports with inexpensive bamboo and string. Whatever you choose, take care not to damage roots or stems when installing the supports.