Do your research to learn what's special about a
perennial like 'The Rocket'
I'm shopping for perennials and wondering what's the
difference between Ligularia przewalskii and
Ligularia 'The Rocket'?
'The Rocket' is the variety name, a common-language label
that follows a plant scientific name. Such a name is given to an
individual of a species when a grower finds something in that one
plant worth promoting over the parent. Usually that variety is then
reproduced by cloning -- dividing or tissue culture -- rather than
collecting and growing its seed, since its seedlings may be as
different from it as it was from its parent.
Growers name varieties for many reasons such as larger flowers,
better color, disease resistance, fast growth or dwarf size. That
difference might not be apparent in the name so you must check a
perennial encyclopedia or catalogue listing. 'The Rocket,' a hybrid
between Ligularia przewalskii and L. stenocephala, was named in the
garden where it occurred by English perennial wiz Alan Bloom
because it "...brought very favorable comment." His description of
the plant in his book "Alan Bloom's Hardy Perennials" forms the
basis of most other write-ups. He rates it "superior" and
"handsome" but he's not specific in what makes this five foot, dark
stemmed shade plant with deeply toothed leaves and yellow spike
flowers better than its parents. That Bloom! He's not just a good
plantsman who's been growing for over 70 of his 90-plus years, he's
a great salesman. He knows that if people say "that's nice," then
you give it a unique name and sell it as special!
Things seem a little pale in my garden. I did
fertilize in spring. Is it possible that all the rain has washed
away the fertilizer?
Entirely possible. Water soluble fertilizers, especially powders
dissolved in water and sprinkled on, need to be applied a bit at a
time throughout the plant's active growth season. Lots of water can
rinse even a granular fertilizer right down below the root zone,
unless it is something like Once or Osmocote that has been
formulated to release slowly over time.
Astilbes are finally going to bloom!
So reports M., who has been trying to grow astilbe to brighten a
summer shade garden and "...tried everything but every year they
turn brown rather than bloom." This year, M. used a new fertilizer
and credits it with the pink blush on his earliest blooming
Not to burst your bubble, M., but you might credit the late
rain, not the fertilizer. Astilbes tolerate a lot of shade and
still bloom, but they are entirely intolerant of drought. Most
years, three early-June coincidences can conspire to ruin the bloom
of astilbe under trees: As the astilbes begin to set flower buds,
the spring rains end and the trees finish leafing out. Since a tree
in full leaf uses an enormous amount of water and an astilbe in bud
will only keep those buds if it stays moist, something usually
gives and that's the astilbe. The buds abort.
For the best astilbes, water more. Never underestimate a tree's
effect on soil moisture. That means you shouldn't set the sprinkler
by the calendar. Turn it on whenever the soil begins to dry out,
even if that's every day.
High time to cut the spring bloomers
Want to keep a rhododendron, azalea, lilac, weeping cherry,
forsythia or other spring blooming tree or shrub smaller than it
wants to be, yet still have a good flower show next spring? Then do
your pruning now and quit for the year. The branches of these
plants must mature this summer in order to set the flower buds by
fall that they'll carry through winter. If you cut after the
beginning of July, you may be removing branches that had set
themselves up to bloom. Replacements that begin forming after early
July may not have time to follow suit.
When you cut now, take off as much height or width as you expect
to get in growth for the rest of the summer, so you don't feel the
need to prune again. That may be 12 inches for a forsythia or
cherry, six for a rhododendron, but it can vary with a plant's age
and location. You know how many times you have been pruning that
shrub in summer, and how much you cut off each time -- do the math
and take that much off in one cut.
Green thumbs up
to gardening all summer. You can sit back after Memorial Day and
enjoy the fruits of your spring labors. However, you can plant in
June, July and August, too, adding color to existing beds or making
a new garden. You can transplant, as well. I have often moved
summer bloomers, in bloom. The keys are watering first, digging big
and watering attentively afterward.
Green thumbs down
to putting the squeeze on as you plant. If the root ball is a
bit too tall for the hole you dig you may be tempted to press down
to force a fit. Resist the urge! The peat-bark mix in most potted
perennials, annuals, shrubs and trees will eventually return to its
original size, rising out of ground to expose the crown and upper
roots to drought, decline and even death.
Originally published 6/19/04