September is the
last month to enjoy the garden. Annuals
and asters have taken center stage.
Roses and some perennials are in the midst of their second bloom. It’s almost the end of the picnic
season. Mosquitos are replaced by
bumblebees, and picnics become an exercise in evasion.
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| Cosmos and Cleome |
The color combinations so carefully
planned for spring and summer are now giving way to the overall anticipation of
autumn, when the trees turn russet, gold and brown. Even the deep reds and purples which seemed
harsh in spring look fine in September.
Enjoy the particular clarity of the September
light. You can ignore a certain disorder
in the garden, unacceptable in spring, but the norm in September. Untidiness is
forgivable in September, because by next month the ferocious pace of bulb
planting will be underway, and once that is complete the garden must be put to
bed. But for the time being enjoy
September; it can be the most restful month in the garden, or the best month for
some hard work. It’s your call.
Week One
This is a good time to shop, as the
end-of-year sales at nurseries will be in full swing. While nurseries can easily hold over larger
trees and shrubs until next spring, to carry smaller materials over the winter
becomes costly.
City gardens are perfect for small
bulbs. Try the smaller members of the
daffodil family, the cyclamineus and jonquillas. Don’t forget snowdrops, crocus spring and
fall, and colchicums.
Each year at this time I wish I had a Clematis paniculata, the autumn-blooming
cascade of starry white flowers covering everything in sight.
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| Sweet autumn clematis |
September is a good time to order
clematis, for they are rarely shipped after mid-October. If you plant clematis in the fall, they will
get off to a robust spring start and you will surely have blooms next
summer. If planted next spring, you are
likely to get only foliage.
Week Two
Most perennials will welcome division
now, but some definitely will not. These include phlox, Shasta daisies, and
Siberian and Japanese iris. Don’t even
try.
The Japanese anemone is the queen of the
fall garden. Starting from a clump of
basal leaves it will grow to three feet bearing several weeks of white or pink
silver-dollar size flowers.
Other September bloomers are False
Dragonhead (Physostegia virginiana),
Brown-eyed Susan (Rudbeckia trilobum),
Bluebeard (Caryopteris x clandonsis),
a low-growing blue shrub better treated as a perennial, Sneezeweed (Helenium autumnale), and Rubeckia ‘Henry
Eiler' (R. subtomentosa).
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| Rudbeckia 'Henry Eiler' |
If rainfall is adequate, little watering
will be needed from now on. The
exception is new plantings and of course roof gardens which will need watering
right up to hard frost.
Bring in pots of amaryllis that have
been summering indoors.
Week Three
Trim long stems of perennial vines and
tie up or train as you like.
Cut back iris foliage to three inches
Don’t let phlox go to seed or they will
self sow, reverting to their original magenta and the new seedlings will crowd
out your carefully cultivated varieties.
Week Four
Last call to bring the house plants
indoors.
Pull out vegetable plants when all the
crops have been gathered and plant a winter cover crop. Winter rye or small grains are good in our
region.
Fertilize lawns and sow seeds in thin or
worn areas.
You can still plant perennials, but they
will have to be protected against the winter’s alternate freezing and
thawing. More on that in November.
Start cutting back perennials. You can compost all but the leaves and stems
of the peonies. These you must discard
or burn.
This is the best time to plant
daffodils, although almost everyone waits at least until October, and often
drag their feet into November. Start
early, and give yourself a gift for 2015.
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| Next Spring's Daffodils |
