For most gardeners, summertime color is a goal we strive to achieve. The reality is we are rarely satisfied, which is why we say a garden is never really finished, but is always a work in progress.
Perennials are terrific for planting once and getting results every year. Many are very hardy, dependable and the backbone of our gardens. Given the very nature of perennials many are available from friends and neighbors just for the asking. Visit their yards to find ones that appeal to you. Be aware that the fabulous photos in catalogs and magazines are rarely what the plant will look like in your garden. Since the plants will be there for years it is a good idea to start by working a well balanced fertilizer, such as 10-10-10, into your perennial bed along with some aged compost or peat moss.
Once established, perennials are not generally delicate plants that need daily watering so they can be left while on a vacation and won’t collapse before you return. The negative to perennials is they have shorter blooming period than annuals, but the blooms are there every year. For summer long color in the garden, select the perennials that bloom at different time and then add a few annuals to fill in with the color pallet of your choice.
Iris are mid to late spring bloomers and generally are in peak form just in time to be a nice backdrop for graduation pictures. Two or three weeks of colorful bloom is about the maximum to expect, but the large showy blooms are worth it. Iris will bloom reliably for many years with little fuss. Dividing the rhizomes every four or five years will keep them going strong.
Lilies are another solid, hardy perennial. Since day lilies are heavy nitrogen feeders, they benefit from regular fertilizing which will enhance the flowering quality of the plants. A liquid fertilizer applied every three or four weeks would be helpful. There are early, mid and late blooming varieties, so pick different ones to have your color display a little longer. There are many good winter hardy varieties, to provide enjoyment for many years. When the clump gets too big, they should be divided, usually every five or six years.
Shrub roses are a great plant for low maintenance and good color. Mine began blooming in late May and will continue through most of June. If they get trimmed after blooming they should re-bloom in late summer. Shrub roses come in many colors and varieties and can be trimmed back to a nice size and shape. They are not the fabulous roses you get on the traditional roses bushes, but they are lovely, fragrant and do not require the work and vigilance. They are not susceptible to the fungal diseases, are winter hardy and do not require covering or burying for the winter. Water, fertilizer, sunshine and they are good for the summer.
Coreopsis is another great perennial with lovely yellow blooms and its soft foliage makes it a nice landscape plant even when it is not blooming. The Zagreb variety is generally the hardier than the Moonbeam variety in this area.
While we don’t usually plant hosta for color, they are a great shade plant. Consider using different varieties of hostas and then plant impatients among them for splashes of color. The impatients will need to be watered regularly.
The Master Gardeners of Anoka County welcome your questions at 763-767-2891. Additional information on a variety of topics is available at the University of Minnesota website, http://www.extension.umn.edu/.
Barbara Harlan is an Anoka County Master Gardener.