is scary? Things that go bump in the night if you’re eight, urban blight if
you’re a city dweller in the crosshairs of a developer and I think we can all
agree on global warming, food contamination, and our diminishing resources as
serious causes worthy of concern. But for most gardeners, scary is the sight of
an innocent-looking plant with a cleanly variegated leaf in white and green
springing from a succulent white root. In an informal survey of gardeners this
spring, bishop’s weed, Aegopodium
was the plant most often mentioned that people regret introducing to their
of us received a start of this “wolf-in-sheep’s-clothing” from a kindly
neighbor (red flag #1). What’s not to like? Bishop’s weed, sometimes referred
to as goutweed, is tolerant of dry shade and difficult growing conditions,
lighting up dark areas beneath shrubs and clothing the ground with its fresh
foliage throughout the growing season, furnishing a clean skirt to emerging
spring bulbs. Later, it knits together compositions of shade garden plants
throughout the summer into fall when it quietly goes dormant with the first
frost. But heaven help you if you decide this seemingly innocent plant—named
for a man of the cloth, no less—is right for you. A more wickedly persistent
and pernicious garden occupant you will never find. Its brittle roots insinuate
themselves deep into existing clumps of plants, under rocks and apparently to
Hades itself, so reliable is its appearance each spring in spite of all efforts
to the contrary. No amount of constant weeding, grubbing out, cutting back and
yes, even applications of glyphosate (Roundup®) seem capable of eradicating
this simple, delicate-looking pest.
constitutes a “scary” plant? While poets might posit that a weed is simply a
plant in the wrong location or one whose best features are not yet recognized,
some plants have developed amazing reproductive capabilities and remarkably
tough constitutions that ensure their survival under frighteningly harsh
conditions. Whether it is tough, resilient energy stores, aggressive root runs,
or rapacious seeding capabilities the following plants are truly scary.
2. Toad flax,
Linaria purpurea—seed. Delicate in appearance with bushy,
upright stems clothed in narrow blue-green leaves, topped by tiny
snapdragon-like blossoms. L. ‘Natalie’ is a sterile cultivar and a
far better choice for the civilized garden.
Verbena bonariensis—seed. Tall branched wiry stems to four
feet are topped by lavender umbels; a beautiful plant with a summer-long
flowering period. Bad news—seeds freely; good news —individual plants are
Pheasant grass, Anamanthele
lessoniana and Mexican hair grass, Nasella
tenuissima are both some
of my favorite ornamental grasses with bronzy-orange and blond tresses
respectively. Their narrow leaves and relatively short (two feet) mounding
forms animate the wind, reflect the light and blend beautifully with shrubs and
perennials in sunny, well-drained soil. They do, however, seed prolifically—but
hey, you’re going to weed something out and it might as well be lovely.
Crocosmia x crocosmiiflora—storage root/corm.
“A favorite for
generations” according to the new Sunset Western
Garden Book, probably
because gardeners have yet to find a way to control this colorful summer
bloomer with its sword-shaped leaves and branched stems of fiery orange
—seed and root run. A cottage garden favorite (another red flag) with bushy
blue-green leaves and stems that produce a long season of small clusters of
crimson flowers…and then seeds into every nook and cranny unless faded blossoms
are religiously removed. A resilient and persistent taproot further insures its
permanent place in the garden.
Popcorn’—root run. An admittedly beautiful golden leaved form of a common
creeping weed tarted up with a given (and tasty) name. A buttercup is a
buttercup, I don’t care what color the foliage is!
This species, not to be confused with its more well-bred kin, produces lank
foliage of a mid-green color and funnel-shaped blossoms in brash hot colors.
Vigorously spreading tuberous roots, while brittle and “frail” are tenacious
and go deep —very, very deep—making this plant nearly impossible to remove. Learn
to love orange cut flowers.
—root run. A colleague fondly refers to this one as “horsetail in a skirt!”
Rapidly spreading underground stems colonize wet ground, or even not-so-wet
ground sending up heart-shaped green leaves splashed with cream, yellow, pink
and red that smell of orange peel or dog’s breath depending on who you ask.
While not garden-worthy, this is a lovely container plant in a water garden
Euphorbia species. In a family as vast and multifaceted
as Euphorbiaceae there’s bound to be some free spirits:
Mrs. Robb’s bonnet, E. robbiae —root run and seed.
An evergreen plant to one foot tall,
able to withstand severe drought, shade, rooty soils and general neglect…see
where this is headed?
Cypress spurge, E.
cyparissias—root run and
seed. Fine needle-like foliage to just eight inches tall, (tinged beautifully
with maroon on the cultivar ‘Fen’s Ruby’) disguise vigorously spreading
rhizomatous roots. I forgive its wanton ways for the feathery ruff it provides
low, sprawling sedums along my gravel paths.
Griffith’s spurge, E.
Beautiful russet foliage emerges nearly hot pink with spring bulbs, unfurling
to about three inches and bursting into blossoms punched up with red to orange
bracts depending on the cultivar. Slower in its inexorable spread, ‘Fireglow’
is too good of a companion to my orange lily-flowered tulips to give up;
beautiful golden fall color as well.
9. Copper fennel, Foeniculum
‘Purpureum’—storage root and seed. Great fountains of feathery bronze foliage
are a magnificent sight in the garden from their teddy-bear-like emergence in
spring to their smoky bulk in late summer topped with golden umbel-shaped
flowers. Young foliage is tasty, ripe seeds are delicious and the blossoms
attract all sorts of butterflies and beneficial insects but oh, how it seeds
and removal of the very substantial root will require the use of a mattock—if
not a chain and a pickup truck.
root/tuber. Some plants just look scary. Huge mottled snake-like stems charge
out of the soil in mid-spring to three feet tall, giving rise to a huge,
two-foot-long maroon “flower,” or spathe, that slowly unfurls over several days
centered with a very suggestive black spadix. Beyond curious in its appearance
this plant is also distinctive for the stench of decaying flesh it emits. I
have been trying to dig mine up ever since it had the bad manners to bloom on
the day of a garden tour, causing visitors to look politely, if not somewhat
cautiously around in search of the dead body that must surely be hidden in the