I have several species of Rudbeckia or Black-eyed Susan scattered through my garden at the moment. And, over the years, I’ve grown more than my share of this hardy, long-blooming member of the daisy family.
Generally speaking – as long as you concentrate on the hardy perennials (and not those sold as perennials but are biennial) then you’ll be fine for many years with the same plant.
They’re a backbone plant for the garden and few gardeners can resist their bright, mid-to-late blooming (and certainly not me)
Here’s what you need to know to grow them successfully in your garden
The plant Rudbeckia was named after Olaus Olai Rudbeck (1660- 1740) a Swedish physician and botanist. Black-eyed is simple – the plants have a black eye. None of my resources tell me who Susan was.
- Bloom time: Early to late Fall
- Height: 24” to 72”
- Sun needed: Full
- Bloom color: Shades of yellow and gold
- Planting space: 18” to 24” apart
- Soil preferred: Moderately fertile, well-drained
- Propagation method: Division, seed
Rudbeckia fulgida is a 24”- to 36”-tall species that is an excellent and long-lived perennial plant in our gardens.
‘Goldsturm’ 24” tall and the most famous of the entire family. It makes an excellent plant for massing or for naturalizing. Its golden flowers shout across the Fall garden to capture the attention of all visitors.
‘Viette’s Little Suzy’ 12 to 18” tall form with medium-yellow flowers. Starts blooming mid- to late summer and blooms right through Fall. Foliage turns deep mahogany in Fall.
All of this family are annuals – and self-sow like crazy in my garden.
‘Indian Summer’ is an award-winning plant and its massive flowers make it clear why this was so. Excellent cut flower and display in the garden. It hasn’t been a prolific self-sower for me.
Rudbeckia laciniata hortensia
This old-fashioned favorite became known as the “Outhouse Plant” in pioneer times because that was usually the place they were found. They are large, strong, relatively fast-spreading plants and this was one place they could grow with impunity. It does require edging every few years to keep it in bounds. It easily hits 8 feet tall each year and has double golden-yellow flowers for the late summer throughout the fall season.
‘Golden Glow’ at 3/5 feet tall is more aggressive than the others and can become a weed if left unchecked.
‘Herbstonne’ can hit 7′ tall.
This is a hardy perennial that grows to 6 feet tall with clear-golden flowers in the fall. This little-known plant is one of my favorite family members. It has a glaucous, blue-green leaf in a mound and the flower stems erupt from that in mid-summer. I’ve never staked mine even with the serious winds we get here on the island.
This is another tall favorite that reaches 5 to 6 feet with yellow to orange blooms.
Grow this plant for its amazing displays of golden-yellow daisies throughout the late summer and Fall. They’ll grow well in the full sun as well as light shade. Regular garden soil is fine but the biennial types do better on lighter, well-drained ground. The entire family makes a good cut flower for the fall dinner-table display.
If you’re growing this plant, you may see leaves start to have a white sheen to them. This progresses until the leaf begins to look as the picture.
A full description and treatment for powdery mildew can be found here.
Botrytis is a fungus, the shock troops in Mother Nature’s arsenal, that’s everywhere. It does bother some varieties in some gardens and here’s how you take care of it.
Rudbeckia Denver Daisy Awarded Top Prize (2010)
The American Garden Award – a popular vote of visitors/gardeners to 18 public garden has just tabulated the votes and Rudbeckia ‘Denver Daisy’ has been awarded first place
As you can see, the bloom has a reddish ring to a golden yellow bloom (with traditional chocolate-brown center). The blooms are 4-6 inches across and the foliage is a deep, dark-green.
In trials this summer, this plant produced well in all weather extremes – from hot and dry right through to wet and humid. Given it is a seed-generated variety, it is readily available from a wide variety of seed companies (don’t look for it on seed racks) this coming year and quite likely better garden centers as started plants.
It is a hybrid of Rudbeckia hirta, growing to 2-feet tall and almost equally wide.
It is not going to be hardy in USDA 4 – and likely not in too many other places given R. hirta (a biennial) is the major parent. Plan on growing this as an annual flower.
It seems that when they breed this plant to produce huge flowers (there are other hybrids of R. hirta on the market) they breed the hardiness right out of them. R. hirta is a self-sowing biennial sometimes acting as an annual or semi-hardy perennial depending on location with a smaller flower. Increasing flower size seems to turn them into annuals so don’t go paying perennial prices for this plant nor expecting it to last forever in your garden.
On the other hand, given the size of plant and flower combined with an extremely long bloom time, it might very well make a great container plant.