One of my favorite, taller perennials for full sun is the ‘Henry Eilers’ sweet coneflower (Rudbeckia subtomentosa) seen in all of these photos. This selection of the native species differs in that it has “quilled” petals that are rolled over and fused…creating a “tubular” look to these pinwheel shaped, 3″ wide blooms. Sweet coneflower is a native plant, hardy to zone 4, that thrives in full sun and shrugs off our hot and humid summers. Exhibiting drought tolerance as well as adaptability in clay, this tall perennial adds color for over two months from late July until mid September. Normally the flower petals are flat but this unique selection was found by Henry Eilers, a well known horticulturist and retired nurseryman, in Southern Illinois along a prairie remnant adjacent to a railroad. This varietal selection was introduced in 2003 by Larry Lowman. Rudbeckia subtomentosa ‘Henry Eilers’ will typically reach heights of 5′ and taller and we’ve seen it get 7′ or so during years with ample moisture. Incidentally the “sweet” reference in the common name had no relation to the flowers but to the foliage which smells lightly of vanilla when rubbed or bruised. Seedlings are not reliably like the parent plant so spring division is recommended for consistency in appearance. While I feel there is ample opportunity for this plant in the back of a full sun border, there is now a variety called ‘Little Henry’ that has the same look but on a more compact plant that tops out at 36″ in height. Both selections will attract butterflies and are also commonly used in a naturalistic plantings and rain gardens.
The weather continues to be fine for outdoor work with temperatures in the mid 30 degrees F and overcast skies. Big John continued processing Holiday Light Show (HLS) supplies for storage. Bill O. came in to organize some of the items we are currently painting for a fresh look this year. Vern worked on a carpentry project. We also saw Jim H., Mark S., Dr. Gredler and many others today. I ordered some more seeds and am almost done with that process. I’m moving on shortly to our perennial and woody plant orders and continued preparations for the myriad events and educational opportunities here at the gardens. I always when people ask if winter is my “down time”! Last night we had a nice turnout of 37 attendees at the second of our eleven monthly Lecture Series topics; New Plants. The next topic is Emphasizing Foliage in the Garden on Tuesday, March 29th at 6:30 pm ($3 for RBG Members and $5 for non-members).
the grass in the foreground (above and below) is ‘Sioux Blue’ Indian grass (Sorghastrum nutans) – perennial
Mark Dwyer, Director of Horticulture, Rotary Botanical Gardens
I am the Director of Horticulture at Rotary Gardens (Janesville, WI). Along with a talented grounds staff and dedicated volunteers, I enjoy being involved with this wonderful botanical resource. My educational background is in landscape architecture and urban forestry but it didn't take long to become a plant enthusiast and find a lifelong career.