I had no idea that my new
perennial was a relative of the domestic sunflower. I saw these plants
in a catalog of native flowers and decided to try them out.
I got a vigorous plant that fills all of my problem areas with
little trouble. This plant has couple of values to the home
owner and naturalist but they come with a bit of trouble.
The swamp sunflower (Helianthus
augustifolius) grows to a height of 6
feet, sometimes better when water is always available. In
the fall it blooms and will continue blooming well into October.
It won't stop all of its activity until a hard killing frost
finally gets it. I have read that some people have trouble
keeping the tall branches standing up but all of my plants have
been strong and upright. In fact, they form a nearly
impenetrable thicket in my corner flower beds.
The thick growth has made a good screen for the
areas of my yard that need to be filled and to keep the neighbors
from seeing my every move. But thick growth means that these
plants can become unmanageable. One of the reasons this
plant can give you trouble is because of its ability to send roots
out for quite a few feet. It would be best to plant these in
a bucket sunk into the soil in order to keep tabs on their spread,
unless you want them to fill an area up. I have seen the
offspring of my mature plants push their way through Black-Eyed
Susan, also known to choke out its neighbors. Talk about
tough. Invasive is a word that could be used to describe the
swamp sunflower.

If you decide to use them in your landscape,
you will be treated to zillions of blossoms about 2 to 3 inches
across through the part of Fall when most other plants are dying
off. When planted in mass, the effect of so many blossoms is
unbelievable.
Once the blossoms die off, they leave behind
seed heads that are irresistible to the birds in our area. I
always leave the stems up for a couple of months into winter so
that the birds can feed until the branches are stripped.
These are great plants to add to your list of food sources if
you're turning your yard into a habitat.
The other reason that these can be hard plant
to have around is the dead branches. These are thick and
when they die turn into brittle rods almost an inch thick in
places. They should be cut back before warm weather starts
but I wait until May many times. It's a lot of work
gathering all the pulled branches into bundles, but when I'm done
I have good tinder material to start fires with.
You can find these plants in specialty garden
shops. Sometimes they are listed under the common name of
Mountain Sunflower. They are native to North Carolina and
other states in the South as far as the Florida panhandle so they
will make a fine addition to you native collection. I found
two varieties at
Niche Gardens. They have a good online catalog and they
will send you a paper one too. If you fell like visiting
their green houses, it's not too far a drive here in Carolina.
Give these plants a try if you would like to
see guaranteed success in your garden.