Late Spring!
When planting a catalpa tree, why not aim for a new
national champion?
Dear Janet,
Where can I purchase catalpa seeds or
trees?
S.M.
Dear S.M.,
The northern hardy catalpa (Catalpa speciosa) is often
called cigar tree or bean tree for its long seed pods. Detractors
call the tree messy for these big pods and its relatively brittle
wood that can lead to some twig fall. Yet the tree's big white
flowers in summer and craggy winter form are assets in the
landscape.
You can buy a catalpa locally if you look around a bit. Use the
internet to find places close to you. There are also places
that will ship the tree to you. Just be sure to use the
botanicle name. Common names can be different depending on
your location.
For seed, just wait until late fall and collect some pods. The
seed sprouts readily with no treatment other than popping it from
the pod before planting.
Dear Janet,
I'm ready to give up and turn my flower bed over to the
thistle weeds growing in it! I dug them out and pulled the sprouts
all last year but they're back, as nasty as ever! Is there any
hope?
C.B.
Dear C.B.,
Weeds have the upper hand in many situations because they're
persistent. So it's only fitting that persistence on the part of
the gardener is one of the keys to beating them.
Here's my standard approach to perennial weeds. It sounds like
you may already have completed the first steps, last year -- so
despite appearances, you're in the home stretch!
If it's a perennial bed, lift the perennials out of the bed.
Take large root balls, mist them, then set them aside in the shade
and they'll be fine for a few hours or even a weekend.
Dig up one thistle and learn what its root looks like -- brittle
and white, in the case of Canada thistle, with thick horizontal
segments. Now dig through the bed methodically, removing every bit
of root you find. Note any place where the thistle root has entered
the bed from adjacent ground, and how deep the roots are running at
that point.
Now rinse all the soil off the root balls of the on-hold
perennials. Remove every bit of foreign root. Replant them. If the
weed was entering the bed from surrounding soil, dig a trench
around the bed or install a vertical root barrier -- making either
the moat or edging material as deep as the weed's runner roots.
Patrol the bed regularly -- daily is wonderful but weekly can
work -- to remove every weed shoot you see. Be sure to "lift the
skirts" of your desirable perennials to roust out the weed shoots
that may be nestled there. Producing such growth uses up starch
from the root fragment at the weed's base. Each day the shoot is in
the sun, however, it creates new starch to rebuild the root. So the
more frequently you nip these survivors in the bud, the sooner you
starve out the remnant roots.
Don't be discouraged in year two. The world wouldn't be green if
Nature gave up so quickly. Despite first appearances, the weed is
weaker this year than last, so keep breaking it off and rooting it
out.
Short reports
If you cut down an ash tree but can't chip
it...
...and suspect the tree was infested with the borers cover
the wood securely with a plastic tarp until next winter. That's
because borer beetles will emerge even from cut wood. Removing the
bark is not an adequate defense as the larvae of this beetle tunnel
into the wood to pupate.
Green thumbs up
to pansies, which seem to have encountered ideal seed
germination conditions this year and are coming up like a green
carpet wherever pansies grew last year. As with other self-sown
species such as sweet alyssum, cosmos, cleome and pot marigold, all
the gardener need do is to thin the plants to leave one every three
or four inches and enjoy your free flowers!
Green thumbs down
to carpet roses as groundcover, firethorn as a wall covering and
barberry as a formal hedge. Why choose such viciously thorny plants
for situations that require regular close hand work? Groundcover
roses must be weeded regularly until established. Firethorn and
barberry need frequent shearing for a formal appearance. Oh, my
poor pricked fingers!
Originally published 5/31/03