Perennial plants that come back every year require less maintenance, which is a good thing. The downside is that many only bloom for a short period of time. You can have continuous color all season long by planting perennials in your flower beds that bloom at different times of the season, so something is blooming all the time.
If you need more plants, you can divide perennials to make more plants. Perennials can become overcrowded and need to be rejuvenated by dividing. An overgrown daylily or hosta can be divided into several new plants.. If you find a perennial you love in the garden center, buy one, plant it, wait a few years, and you’ll be able to divide it and have more plants.
Nature is capricious, so the plants bloom when they consider the conditions are right, so it’s hard to show a specific date, but here is when to generally expect the first blooms in USDA plant zone 4.
Bloom Times for a Few Common Perennials
March-April – helleborus (lenton rose), crocus, daffodils, hyacinth, candytuft, brunnera, pulmonaria
April-May – Virginia blue bells, muscarii, campanula, poppy, baptista, potentilla, anemone, iris
May-June – creeping phlox, ajuga (bugleweed), lungwort, peony, iris, clematis, hollyhock, monarda, agastache, butterfly weed, baby’s breath, shasta daisy (and weeds!).
June-July – daylily, hardy geranium, red hot poker, coneflower, lavender, agastache, lady’s mantle, garden phlox, coreopsis, liriope, hibiscus, delphinium, black eyed susan, astilbe, cardinal flower, Russian sage, gaillardia,
July-August – helenium, oriental lily, liatris, allium, salvia,
August-September – sweet Autumn clematis, aster, sedum