Curtail the spread of ivy and myrtle with a perimeter
You wrote about keeping invasive plants from crossing
into your yard by putting plastic into the ground like a buried
wall. Wrong! I've tried that to keep out myrtle on one side and
English ivy on the other. That edging doesn't even slow them
Don't print my name or city. My neighbors mean no
You're right. But we're discussing two different kinds of
plants. Sorry for the confusion.
I wrote about "...running-root invasive plants (like Mexican
bamboo)" on July 26. Myrtle (Vinca minor) and English ivy
(Hedera helix) are in another group, of plants that do
most of their spreading by creeping across the surface. Beneath
branches that sprawl beyond the established colony the soil stays
moist, cool and dark -- perfect conditions for this kind of plant
to form roots on the underside of the stems.
Other groundcovers that spread primarily above ground are
wintercreeper (Euonymus fortunei), ajuga (A.
repens), strawberries, barren strawberry (Waldsteinia
fragarioides), thyme and creeping phlox (P.
subulata). A number of weeds travel the same way, notably
ground ivy or creeping charley (Glechoma hederacea) and
To bar these overland creepers use a horizontal barrier, such as
a perimeter path as wide as the branches tend to grow. Cut
interlopers regularly or spray them with herbicide before they
When ivy fails
D.W. needs help with large areas of groundcover ivy that
have thinned and become infested with weeds.
All plants get old, and have bad years. Yours is old if it's
been there ten years or more, and this year all evergreen ivy had a
tough winter. When they die out, bare spots develop where other
plants can get started. Kill or dig out the weeds -- and the ivy
they're tangling with. Loosen the soil and add compost. Plant new
starts, mulch the area and keep it weeded and watered until the
replacements fill in.
Switching to another groundcover species. or a quilt of two or
three, is not a bad idea, either.
Perennials can stand in for shrubs
G.C. is realizing that a mystery plant she thought was a shrub
is just a very large perennial. It happens, G.C.! Many perennials
can stand in for shrubs, so long as you don't need a woody presence
in winter. Some perennials that rival shrubs in size and blow them
away for summer show are Joe Pye (Eupatorium purpureum),
ironweed (Vernonia species) and blue globe thistle
Ants and plants can coexist
P.S. and others have noticed ants in abundance this year
and wondered what to do. The answer is probably, "Nothing."
Ants belong in the soil and can coexist peacefully with plants.
Sometimes ant numbers can be so high that the tunneling causes
roots to dry but then it's not ants you'll wonder about but wilting
plants. Some types of ants "farm" aphids, even moving them between
plants, but that's not the main source of aphids.
If you grow aphid-prone plants, whether you see ants or not, you
should hose the plants frequently with a hard spray of water to
keep the aphid numbers down.
Can that ash be saved?
B.M. wants to know if an ash tree can be saved from emerald ash
borer with injections.
There are no guarantee except that whatever you do in the way of
protection you will have to keep doing every year. If you have a
very important ash tree that shows absolutely no sign of emerald
ash borer damage you might call a tree care company about
injections in spring or spraying in summer. Yet by the time the
average person notices damage, it's too late to treat.
We're taking down more than a dozen ashes for my in-law's today
-- I'm probably cutting and dragging wood as you read this. Then
we'll plant substitutes. I feel it's the best answer, considering
the continuing cost of treatment and the fact that no reliable
results exist to determine if any of the possible protocols work or
Green thumbs up
to learning from what grows well on highway shoulders and
medians. Scholar trees (Sophora japonica- how nice to see
white flowers in August!) thrive in the median , so you know they
don't need coddling in terms of water, fertilizer and weeding. You
can also guess that low, scrambly fragrant sumac (Rhus
aromatica), surviving and spreading among aggressive roadside
weeds, may be more that you ask for -- an invasive in a "normal"
Green thumbs down
to people who dump non-compostables at yard waste collection
sites. Stern looks, too, to those who see but don't immediately
report this to the site manager. Most such sites are tax subsidized
and our only link to low cost compost and freedom from making
compost ourselves. Don't ruin it for all of us by being too lazy to
bag and drag curbside things that will ruin the site's shredding
equipment, devalue the compost, raise the price or end this
Originally published 8/9/03