Monday, June 18, 2012

Time to cut back the Asters

Driveway garden before cutting back...
If you are growing tall native asters or goldenrods, mid-June is a good time to cut them back by a third to a half.  This will give more blooms on a slightly shorter plant.  It also reduces the tendency of these plants to flopping over.  I did this yesterday in this driveway garden.  Prairie Aster (Symphyotrichum turbinellum) dominates the right side of this planting.  Cutting back not only reduces flopping, it also makes it easier to see some of the other plants, like purple coneflower and common milkweed.  

After cutting back its easier to see the shorter flowers
I have cut back asters as late as the end of June.  Goldenrods can get the same treatment, but I found that I severely reduced the number of flowers on the early blooming Stiff Goldenrod (Solidago rigida) by cutting back too late in the season.  The later blooming Seaside Goldenrod (S. sempervirens) did just fine.

Two stalks of Canada Toadflax

As I was cutting back these fall bloomers I noticed several clumps of the native Canada Toadflax (Nuttalanthus canadensis, formerly Linaria canadensis) in bloom.  I have been seeing these along the highway since the beginning of June, but this is the first time I have been moving slow enough to get a good look.  They usually show up in large masses and can look like a pale blue cloud while driving by.

This winter annual or biennial wildflower grows in full sun and rocky soils where they have little competition from other plants.  The one in this photo was growing right on the edge of the asphalt, despite having much better soil nearby.

Close-up of Toadflax flower