Jane's Garden 5/25/14: Black-eyed? Brown-eyed? Susans are always beautiful

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Black-eyed Susan is one of about 15 species in the Rudbeckia genus, native to North America. Some are annuals which grow, set seed and die within a year. Others are biennials which sprout and grow one year, flower and set seed the next then die. A few are perennials which last many years. Rudbeckia perennials are deciduous in winter, even in relatively warm Central Florida.


All Rudbeckias have composite, daisy-like flowers, usually with yellow ray petals around a central, prominent cone or disk. Flowers are single, double or semi-double, 1 to 2 1/2 inches in diameter. The raised cone may be black, brown, greenish, rusty or purplish. Common names are Black-eyed Susan, Brown-eyed Susan, Coneflower and others depending on local custom and names passed down in a family or community. Using the scientific name avoids confusion. This name is easy to  pronounce: Think of a “rude child named Becky.”

Two years ago, I planted four little clumps of perennial Rudbeckia ‘Goldstrum’ from 4 inch pots on each side of a grassy driveway. Plants were about 18 to 20 inches apart. 

These plants multiply mainly by growing offsets on root runners radiating from the parent. To make the garden tidier, I had cut off the dead flower stalks, called scapes, in November. The saved seeds were broadcast in empty spots in the garden early in March. As ‘Goldstrum’ is a manmade cultivar, seeds are usually sterile.

When the eight driveway clumps put up leaves in mid-April, they showed each clump was more than 14 inches in diameter. They could be left for another year before dividing the clumps, but I had a little spare time and volunteer in the gardens at Dunnellon Library. There is plenty of room for Black-eyed Susans at the library, so this propagation addict took action.

I filled 6-inch-diameter black reused flower pots with a soil medium made of half backyard sand and half finely milled mulch from Central Landfill on State Road 44 west of Inverness

 This fine mulch is free and made from yard waste. The milling contractor is paid from the fee collected when these organic materials are dumped for recycling. Any weed seeds are dried and cooked to death in the more than 130-degree heat of decomposition.

The first Rudbeckia clump was dug up. I dug straight down about 5 inches beyond the outermost leaves so as not to cut any roots. 

The ball was almost 2 feet in diameter. I shook off as much soil as would fall easily. Then, with a sharp kitchen knife, I cut it in quarters in the middle through the thick, fleshy, main root. 

Next, little plantlets on single roots with many fine feeder roots were cut as long as possible. Three of these rooted plantlets were held in a pot with 2 inches of soil in the bottom, then more soil mix was poured around the roots.

Tapping the pot lightly settled soil around the roots without damaging them.

More plantlets were teased from the main plant with minimal root damage. These were quickly planted in 6 inch pots, tapped and flooded with a soft shower from the water hose before any roots could dry out.

One clump of Rudbeckia produced enough plantlets to fill 21 six-inch pots. They were put under Turkey Oak trees my backyard nursery. The nursery gets overhead irrigation twice a week if there is no rain.

The new plants were watched during the first week for signs of drying, but never needed more irrigation, as they had adequate feeder roots to take up water. 

Part-shade conditions slowed evaporation. After a week, I left to visit family in Canada. These Black-eyed Susans grew twice as big by the time I returned.


Jane Weber is a professional gardener and consultant. Semi-retired, she grows thousands of native plants. Visitors are welcome to her Dunnellon, Marion County, garden. For an appointment, call 352-249-6899 or contact JWeber12385@gmail.com.