I have been growing Japanese yellow sage for four or five years now.
My start was a gift from a gardening buddy who obtained his start from
another collector. Salvia koyamae has been exchanged among collectors for
some years and is now beginning to show up more often in nursery catalogs.
Perhaps it is time for you to be come acquainted with this unusual salvia
that prefers a woodland environment.
I was not sure exactly what to do with my gift, for my mind had always associated salvia with sun. So, I compromised and transplanted my start to a large container based upon the leaf size and placed it in bright open shade.
The woodland sage behaved so well in a container that I almost left it there permanently. It was especially nice when the stems trailed over the edge and down the sides of the container. I also got luck in choosing a dark colored container that showed off the foliage and bloom to best advantage. But, moving the large heavy container in and out of protection during winter became a chore, so I found a home for it in my garden.
Japanese yellow sage begins blooming in July for me, and continues well into fall. The hairy soft-yellow blooms are on short spikes above the foliage. I consider the blooms a bonus, for it is the foliage of this woodland salvia that interests me most.
The stems reach about fourteen inches in height and arch over to
trail on the ground. If conditions are right, the stems can root at the
nodes along the declining stem forming a groundcover of good size. If it
begins to claim more territory than you allowed when transplanting to the
garden, then pinch it back, or rip out a shallow-rooted stem. Pinching it
back encourages a more bushy and full plant. Do give it at least four feet
in diameter. The plant will fill that space in about three years.
Each leaf can reach over seven inches wide by eight inches long and is softly downy to the touch. Foliage is a soft felt-green that approaches chartreuse in color. There is a gentle quiet presence about Salvia koyamae.
There are no demands to growing this plant well. Simply give it decent woodland soil with some humus, a bit of mulch that is on the light side, and bright open shade. It is not touchy about transplanting and after established, stands up to our dry shade conditions of July and August.
In my garden Japanese yellow sage has found a home with several companions. Primary is a stone bench carved for one person that the salvias frames on each side and then backs. To the side is a container with earth ware color and a tender bulb. To the rear are two fairycandles (Cimicifuga) with dark foliage that complete their bloom cycles just as the saliva begin theirs. The fairycandles are used for foliage contrast with the salvia. Other companions you may want to consider are large ferns, hosta of medium to large size, helleborus foetidus.
Salvia koyamae is offered in this fall's inventory. Look for it in our list of plants.