The three season garden means that we’re designing a garden to flower continuously during spring, summer and fall.
In warmer climates, it is quite possible to design for having some bloom in the garden for 12 months of the year by using perennial flowers such as Hellebore and early shrubs such as Fragrant Wintersweet.
But for most of us, we want to see those gardens in bloom from spring till summer.
In your perennial border, divide the border into drifts or spaces in which you’ll grow 3-5 plants of the same variety. This will give you large blocks of color in each garden “drift”. Larger blocks of color mean the garden is more impressive than smaller color swatches – individual plants tend to look lonely. The color pictures you drool over in garden mags are usually more than a single plant (even though it usually only looks like one plant – there are multiple plants in the space).
A simple backyard perennial border
Divide the number of drifts you have by 3. So if you have 21 drifts, the divided number is 7. Plan on putting seven blocks of spring blooming plants into this garden. Then add seven blocks of summer blooming plants and seven blocks or drifts of fall blooming plants. In this way, you’ll have equal sizes of drifts of spring, summer and fall blooming plants in your garden. You’ll have something in bloom in all seasons of the garden.
Wider And Bigger
Yes, this means your garden has to be wider and bigger than you thought.
When it comes to choosing plants, pick varieties that are long blooming. If you’re picking a daylily, pick from one of the newer varieties that is a repeat bloomer. If you’re putting in Iris, do the same thing. Pick plants such as Phlox paniculata (Garden Phlox) that bloom for a really long time.
Spring bulbs can exist under trees and shrubs if they get enough sunlight in the spring before the woody plant leafs out.
Bulbs Under Shrubs In A Three Season Garden
Use bulbs underplanted under shrubs to give you a head-start on spring color.
Use annuals throughout the garden so their season-long blooms will carry your three season garden through when your perennial blooms are a little weak.
Consider Colored Foliage
Use colored foliage for the same reason. If you can find a perennial that has good blooms as well as colored foliage, use it. You can get great color from both the blossom and leaf and this is a good design habit to get into.
Don’t hesitate to use tropical foliage plants with their wildly colored foliage to provide a season long color. The same goes with herbs and some of the foliage effects they produce.
Shrubs For Blooms
Shrubs can give you early spring blooms as well as some excellent foliage and fragrance so do plan for their blooms. For example, Potentilla shrubs will bloom most of the summer if kept fertilized and watered.
Roses are a “must” in any three season garden. Their long blooming time and fragrance is critical in my gardens.
A miniature rose flowering next to a statue in my own garden. I often pick these roses up on the remainder table after Valentine’s Day. Give them a haircut and in the spring, plant them outdoors. They’ll usually bloom again all season and most of the time, they’ll survive the winter.