"GARDENING COACH" COLUMN FOR NOVEMBER 2006
Okay, a quick review in case you didn’t memorize Part 1.
Sustainable gardening practices are those that don’t damage the earth
or waste resources. Definitions vary all across the board but that one
has broad support. And for eco-conscious local gardeners I’ve looked
far and wide for plants that are:
– Drought-tolerant. Since
most drought-tolerant plants are Mediterranean and need good drainage
if they’re to survive our winter and esp for winter and wet springs.
So berms are helpful, plus well-draining soil a must. Also, no low
spots or poorly draining clay soils. And if your site is a
consistently soggy one, drought-tolerant plants won’t work. (Google
plants for wet soils.)
-Resistant to disease and severe insect damage. Minor insect damage? Get over it.
GOTTA BE NATIVE?
Another criteria for the "sustainable"
label used by some sources is that plants be native, a word I interpret
to mean locally native. (Why? Because no other definition makes any
sense. Plants don’t behave according to political boundaries like
"native to the U.S.," and the U.S. includes waaay too many different
ecosystems to provide horticultural guidance in the first place.)
Here in the Mid-Atlantic area the native ecosystem is that of
deciduous forest and almost all the native plants are woodland,
shade-loving ones, not the desert or rock garden plants that tolerate
sun and drought. So I’ve included as many locally native garden plants
as I could find but there just aren’t many to choose from. (The Plains
of the Midwest do provide a considerably larger selection, however.)
A FEW DISCLAIMERS
– Even the most drought-tolerant
plants for our area require careful watering during their first year,
sometimes longer. So don’t assume a plant is drought-tolerant until at
least its second full season. This is especially true of any plant
installed in the spring (which is why fall planting is best!)
I found contradictory information about some plants, with the
literature saying one thing and local gardeners another, so I’ve noted
them as "possibly" sustainable.
– Some plants listed here are on
watch lists for possible invasive behavior because of reports from
other parts of the country (nandina, liriope, ornamental grasses,
butterfly bush, and daylilies) but no locally listed invasive plants
have been included.
– I’ve used primarily common names for reasons of space and public recognition.
LOCALLY NATIVE SUSTAINABLE PLANTS
Grasses: Big and Little Bluestems.
Threadleaf coreopsis, Liatris, Rudbeckias (including black-eyed susan),
goldenrod, common evening primrose, Butterfly milkweed, wild columbine,
New England aster, wild bleeding heart and possibly Amsonia, Bee balm
and Joe Pye Weed.
Shrubs/small trees: Flame azalea, American beautyberry, Serviceberry, several sumacs, Witch Hazel and Pasture rose
SUSTAINABLE PLANTS THAT AREN’T LOCALLY NATIVE
Grasses: Carex, Dwarf mondo grass, Liriope, and most larger ornamental grasses
Agastaches, Asters, Baptisia, Chinese Fringe Flower, Daylilies,
Dianthus, Epimedium, Hellebores, Heucheras, Hostas, Mazus, Purple
coneflower, Rudbeckias, Sedums, Penstemon digitalis, Russian sage, Salvia (hybrid sages), Sempervivums, Sweet Autumn clematis, and Yucca.
trees: Abelias, Aucuba, Azaleas, Beautybush, Butterfly bush,
Caryopteris, Cotoneasters, Crapemyrtles (especially those with Indian
names), Deutzia, Forsythias, Fothergilla, Hydrangea paniculatas,
Oakleaf Hydrangea, Asian and hybrid dogwoods, Junipers, Lespedeza,
Mahonias, Nandina, Photinia, Rugosa roses, Sarcococca, Spiraeas,
Viburnums, Witch Hazel, Weigelia, Winter jasmine, Yaupon holly, and
– These popular plants in our area
really don’t like drought: Japanese maples, snowbells, rhododendrums,
big-leaf hydrangea, boxwoods, and our native dogwoods (Cornus florida).
These dogwoods flunk our sustainability test because they’re vulnerable
to the disease anthracnose. (SP?)
– Some drought-tolerant
plants (like artemesia) have been excluded here because they hate our
humidity, so ask enough questions of the nursery staff.
some plants that always look sickly or that require constant vigilance
during even moderate droughts? Consider getting rid of it. You’ll be
glad you did.
Thanks to my contributors: Larry Hurley of Behnkes; Peggy Bowers,
horticulturist at the American Horticultural Society; Jim Adams,
horticulturist at the British Embassy; Pat Howell of Deephaven
Landscapers; Mike Welsh, Takoma Park’s City Gardener; Donna Shipp,
horticulturist at American Plant Food; Joel Lerner via the Washington
Post; Derek Thomas, local landscaper; the highly respected Carole Bergman and others in the
Maryland Native Plant Society; the NC State Cooperative Extension
Service website and other many other websites.