Rudbeckia triloba, 3-lobed coneflower,
is biennial in nature but usually lives
more than 2 years. Very prolific seeder.
Cutting most of the flowering stems
down to basal foliage after flowering
will prevent literally hundreds of
offspring from developing, although
you should allow some seeding to
ensure permanence of the species in
the garden. The stems that are allowed
to remain will fall over in the winter
but are still enjoyed by the birds. The
basal foliage remains evergreen.
Plants have a tendency to flop
during flowering and may require
staking. In a garden setting, pinching
or cutting back may be desirable for
sturdier growth. Plants pinched or cut
back by about a third when 2 ft. tall in
early June flowered at about 4 ft., rather
than 5 ft., with only a slight delay in
bloom time. Cutting back further may
be desirable to produce even shorter
plants with a greater delay in bloom.
Flower size is not noticeably reduced
after pruning. A native plant, it is good
in a naturalized area where free
seeding and flopping are permissible.Rudbeckia nitida
‘Herbstsonne’
‘Herbstsonne’ coneflower
compoSitae
Golden-yellow, daisylike flower heads with
drooping petals; bright green leaves
7 ft. (2 1/2 ft.) high; 3 ft. wide
Full sun
Blooms July–August
Zones 4–10
pruning This coneflower has a long
season of interest even without
deadheading. Not a plant that could
easily be deadheaded anyway by all
but the tallest of gardeners without
the aid of a step ladder. Attractive
seedheads extend the season of
interest and bring birds into the
garden for feeding. Seeding is not
usually a problem with this species.
Although often touted as having
self-supporting stems (perhaps in
more northerly gardens), plants in my
garden topple over unless given light
support. The wonderful height is one
of the main reasons to grow this plant,
but cutting back or pinching could beRudbeckia fulgida ‘Goldsturm’