I have added some seasonal shrubs to my borders, shrubs that have three seasons of interest.
Ninebark Summer Wine
Grasses are also great to add for multi-season interest, but they must be cut down each spring and divided when they develop a donut look in the middle.
Roses are work in my garden, pruning, deadheading, fertilizing and oh those Japanese Beetles! A local nursery uses the traps and I am going to try them this year before I give up growing roses. I know the traps are controversial but I am the major rose grower in the neighborhood so I get most of the beetles anyway. Don't get me wrong, I love the roses, they are a wonderful addition to my back borders. However, for the past few years I have been getting only one bloom cycle and the rest of the summer is spent trying to get rid of the beetles.
David Austin's Mary Rose
You can see why I hate to give them up but they are an eyesore most of the summer.
Phlox are a little more work because if you want them to bloom throughout the summer they must be deadheaded. They have long legs that are prone to leaf curling and should be planted behind shorter plants so they just peek out.
Taller Franz Schubert with Laura
Colorful leaves can be as pretty as flowers and require almost no maintenance.
Brunnera Jack Frost
Brunnera Angel Wings
Heucherella Sweet Tea
Heuchera Pinot Gris
Heuchera Autumn Leaves
We must not leave out hostas and ferns in the carefree garden (many will grow in the sun).
Halcyon and August Moon hostas will both take sun.
Lady Fern Red Stemmed
Lilies are always carefree! My favorites are the Orienpets but try to stay below four feet in height unless you want to be running around staking the tall ones. They are lovely but will not hold up to high winds like the shorter varieties.
Lilies can be planted in the fall and spring, take up very little room in the garden.
Daylily Chicago Rosy
Choose daylilies that do not require division for many years. Stella D'oro multiplies so fast you will be on your knees a lot trying to keep it contained.
Ten years and have not had to divide yet!