Growing acid-loving plants is a challenge in southeast
I want to grow mountain laurel (Kalmia
latifolia) and wonder if anyone in around here has any
experience with them.
In particular I wonder how much sun they need. Different
nursery catalogs and web sites have conflicting recommendations for
them to be placed in full sun, partial shade or shade. And I have
run across comments ranging from "does not thrive in full sun" to
"tends to exhibit sparse and irregular branches and blooms
infrequently when placed in shade."
I am looking at putting them on the northwest side of my
house in an area that only gets a little sunlight very late in the
Kalmia latifolia is a broadleaf evergreen with showy
spring flowers. It's native in acidic soil areas of the
northeastern U.S., in and along the edges of older forests of mixed
pine and oak. It grows below high-limbed trees where openings admit
light, not in the dense shade of closely spaced, low-branched young
Growing Kalmia in alkaline soil is do-able. But it's a challenge
as is growing others in the acid-loving heath family, such as
rhododendron, blueberry, heather and Pieris japonica.
More energy means better bloom. So plant Kalmia in as much sun
as possible, at least 6 hours of light per day during the growing
season. Count November and March sun, since these plants can
photosynthesize any time it is not so cold or dry that their leaves
roll up. Choose a spot that's like a woodland -- protected from
drying winds, with an overhanging canopy that tempers daily
temperature fluctuations and soil that is always cool and moist
without ever being soggy.
Amend the soil with organic matter and soil sulfur to make it
loose, well drained, moisture retentive and acidic. Mulch with
acidic materials such as pine needles, cocoa hulls or coffee
grounds. Fertilize at intervals during spring and early summer with
acid-loving plant fertilizer. Water faithfully, preferably with a
slow drip from April through October.
Even at its best, Kalmia latifolia becomes open in the center
with age. To counteract this, prune established shrubs to cut out
two or three stems close to their bases every spring. This will
keep new growth coming in the center.
Contradictory recommendations are understandable, since these
plants are grown across a wide area. In the heat of the South, too
much sun will kill them. Under low branched maples on a lawn where
it's shadier than in an old woods, these plants may not get enough
light to be full or bloom well.
Sorry, you can't root and grow a cut Christmas
In a January 15 short report I wrote, "You can transplant that
live Christmas tree."
N.G. writes that she and family have had, "quite a discussion
about this. We do not understand your definition of a Christmas
tree. Do you mean one that has been cut and decorated for
Christmas? ...when you talk about a root ball that mixed me
I meant a tree used as a Christmas decoration yet intact,
with roots still potted or in burlap wrap.
To gardeners who think it must be rare for people to imagine a
cut tree being replanted: Dispel that notion. Remember that what
you do can seem magical to others. One time I learned only by
accident that a man who overheard me talking about planting a
Christmas tree also had a cut tree in mind. He had decided that my
green thumb extended into the supernatural range.
I enjoy answering questions you mail to me or post on my
school's website. However, some problems have no solution. Don't
expect much help from me if you pose a "stumper" such as: Why is it
that people who like intricately curving bed edges usually find
themselves sharing yardwork with someone who is only willing or
able to mow along straight lines and simple bends?
Green thumbs up
to the Building Industry Association representatives who
encouraged development of and then attended the class "Avoiding
Construction Damage to the Landscape" at The Michigan School of
Gardening. They showed their willingness to learn about the
specific impact their work has on a landscape, what constitutes
effective plant protection and how they might assist clients who
plan to preserve their landscapes. Ask if your builder or remodeler
has done this. Or, take the class yourself. It's for both builders
and property owners.
Green thumbs down
to construction workers who insist on parking within arm's reach
of their work sites because, "I need things in my truck and it's
costly for me to walk back and forth all day." When you drive on
lawns and gardens you damage soil, roots and plants immediately and
in ways that can take decades to remedy. Rethink your position in
light of that greater cost. Or consider the fact that my carpenter
grandfathers as well as today's plumbers, professional gardeners,
arborists and even me, in my first career installing phones and
wires, could plan well enough to work efficiently from trucks
parked on the street.
Originally published 2/5/05