Gardening questions
Dr. Leonard Perry, Extension Professor
University of Vermont
Three questions many ask us in Extension this month include how to
establish a wildflower garden, how to get rid of Japanese knotweed and
poison ivy, and the best method to overwinter geraniums and coleus indoors.
The common misconception is that you can just scatter wildflower seeds
anywhere, as nature does, and end up with the same effect. The difference
is that nature uses millions more seeds than you can afford! So you
must prepare a fine seedbed, as you would for seeding a lawn.
Make sure all weeds are removed, a process that may take a year or
two. Chemical herbicides may be used, but residual ones (ones that last
in the soil) may also harm your subsequent wildflowers. You may cover
smaller areas with black plastic for a year. Repeated tilling, with
cover crops, may also be used. Then sow seeds on this fine bed, into
which an organic slow-release fertilizer has been incorporated.
Make sure you use a mix containing primarily native species. Otherwise,
you may just end up with pretty annual flowers, native to California
for instance. Keep seeds well-watered regularly until they germinate.
You may need to keep the area weeded, as weed seeds blow in or germinate,
at least for the first year or two until your desirable plants are established.
Poison Ivy and Japanese knotweed are very vigorous weeds Eradication
requires persistence says Margaret Hagen from the University of New
Hampshire Cooperative Extension. She suggests repeated mowing over several
years to deplete stored root reserves of food, eventually killing the
plants. This means three or more cuttings in a season. Just make sure,
if cutting or weed trimming, not to get sap or plant parts of poison
ivy on you.
Grubbing or digging out the roots may help, but missed ones can sprout
and regrow. An alternative to digging, once the tops are removed, is
to cover the area with heavy black plastic. Anchor it with rocks or
metal pins, and leave in place for a year. Herbicides also may be used.
Check with your local full service garden center on recommended ones,
and be sure and follow all label precautions and directions.
If you plan to bring coleus or geraniums indoors for winter, Dr. Lois
Berg Stack from the University of Maine Cooperative Extension recommends
digging plants in late August before nights get too cool. Pot, water,
and leave outside in shade for a week to acclimate, then bring them
indoors. Make sure an bring in healthy plants, and ones without insect
pests.
Place them in south or southwest windows for the brightest light possible.
In low winter light, geraniums may stop flowering and coleus may lose
their colors. In spring, cut back the plants and allow them to develop
strong new growth outside in full light. Just make sure to protect from
cold and frosts such as by bringing back inside.
An alternative to overwintering whole plants is to root stem cuttings
in late August, pot, and keep indoors. When new growth develops, pinch
it back to encourage branching.
http://pss.uvm.edu/ppp/articles/augquest.html