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http:www.simplegiftsfarm.com

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Plant Thugs:

Plants That Come With a Warning

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Plant ThugsCopyright Douglas Green 2005

All rights reserved. No part of this book may be used or reproduced or transmitted in anyform or in any manner whatsoever without the express written permission of the author.

ISBN 0-9737813-2-7

Dougs home page at http://www.simplegiftsfarm.com

Dougs Blog at http://www.simplegiftsfarm.com/gardens-gardening-news.html

More perennial information at http://www.gardening-tips-perennials.com

Normally an author dedicates a book to somebody they want to honour. Ive dedicated

books to my kids, to good friends, to parents.

Who would want a book called Garden Thugs dedicated to them? Who would speak tome after such a thing?

There are two gentlemen (and I use the term loosely) who could appreciate the finehonour of this moment. These are punsters-in-arms, members of an elite quipping team

that has conquered many a dull moment and dulled many a fine moment. These are men

who know and give no quarter if they could give a dollars worth of praise. One of whomindicates hell run somewhere if Ill tell him what to do when he gets there. So I did.

The other simply feeds me beer and asks me to lift insanely heavy objects so he can nail

them to his house. So I did. Good friends both.

I thereby dedicate this tome to the other two Gentlemen and fellow members of SOW

Big Thugs to Both of You

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Introduction:

One gardeners curse is anothers blessing. What I would never allow into my garden

even in a plastic bag for a five minute visit is welcomed with open arms by othergardeners.

These are the certified plant thugs those plants that spread and never met a patch of

ground they didnt like.

Yes, they make ground covers if you want a plant to cover waste areas laid low by

explosions or fire. Yes, they will survive where other plants fear to tred so they do have a

point in our garden world. But for the most part, they should be tended in those faraway

places and not allowed a toehold in the good garden. Not even allowed a toehold nearagood garden.

Because make no mistake about it, these plants are only controlled with the most extremeof measures. Once admitted to fertile soil and decent watering, they will smother and

take over a garden. They will eat the other plants and smother the life out of them.

That is why we call them thugs.

You have been warned.

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Aegopodium

Some people think this plant is cute. They actually plant it inside their perennial borders.

Then they realize how invasive it was. It will invade and choke out most other perennial

plants.

Height: 12 inches

Flowers: insignificant, dirty white

Distance to Plant Apart: A city block or 18 inches

Sun or Shade: Yes.

Soil: Yes. Although really dry soil tends to make it look quite floppy and ugly

Varieties: Believe it or not, this plant comes in aplain green form as well as a green and white leaf

variegated form. The variegated variety will revertto green here and there and these should be dug out

or they will slowly dominate.

Cultural tips: While it seems perverse, this plantcan actually look quite attractive in early spring

when the foliage is tight and neat. It starts looking

floppy and really ugly later on but the cure for thatis to run a lawn mower over it (seriously!) or cut it

to the ground with a whipper-snipper. The resultingnew growth will be tight and compact lookingagain. And no, this will not (unfortunately) hurt the

plant or set it back.

To eradicate this plant, start digging. It is

relatively easily removed from a garden over a few

years. Every bit of plant root you leave

underground will resprout a new plant, so it does take a few years of digging to get themall. If the plant is in the sunshine, clear plastic can be used (see sidebar)

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Anemone sylvestris

This is a wonderfully attractive native Anemone with small clear white flowers in mid-

summer that I let get a foothold in the perennial border at the front of the farm property.

Im not sure the perennial border is there any more but I can guarantee you that Anemoneis. I never knew a plant that I couldnt get rid of but that one was as close to it as I ever

want to see. Pretty little thing but man, could it grow.

Height: 18 inches

Flowers: 1 inch across, white

Distance to Plant Apart: one plant will do it, no need to plant more.

Sun or Shade: Seems to prefer sunshine.

Soil: did very well in well-drained sandy soils.

Artemesia ludoviciana Silver King and SilverQueen

This is one of those oh-so-fashionable grey or silver leaved plants that garden mavens

rave on about. What they dont tell you is that theres a lot of raving to be done. This is adown and out thug (both the king and his queen) and they resemble conquering royalty

rather than gracious hosts that share garden space. They do make wonderful cut and

dried plants so there is at least oneredeeming use for them but they

spread too fast to have much use in

the main perennial border without a

tremendous amount of care. You canshear them in midsummer when they

start looking rank and this will bring

them into a bushier look.

Height: 24 inches

Flowers: white sometime in early summer

Distance to Plant Apart: 24 inches.

Sun or Shade: Full sun if you must

Soil: They prefer a well-drained location. Too much fertilizer makes them floppy andthen you have a floppy, aggressive plant.

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vinegar will not change the pH of the soil at least not for more than a week according

to modern research.

What about Roundup? In the past, Roundup has been one of those wonder sprays that

were extremely effective as well as being environmentally safe. Recent research has

pointed out that the one possible reason the worlds frog population is dying out isbecause Roundup or one of its components is extremely toxic to tadpoles. A bit of this

product in the watershed and the tadpole population crashes. There are other reports

coming out about the safety of Roundup and given that it is the number one agricultural

chemical used in the world today, these reports have to concern us all.

Given that vinegar works albeit slower but much safer I have to recommend

agricultural vinegar rather than Roundup.

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Cerastium tomentosum

Cerastium or snow in summer is a grey leaved plant that I last saw eating a neighbour's garden

quite contentedly. The gardener in question didnt know the plant and accepted a division from a

friend who had lots. This is a weedy looking plant with no flowers to speak of that pops up

here and there by underground rhizome. It is sold as a ground cover.

Height: 24 inches

Flowers: dirty white sometime in early summer


Sun or Shade: Yes. Sun or part shade

Soil: It never met one it didnt like

Houttuynia cordataThis heart shaped leaf plant is purchased by unsuspecting gardeners because of the multi-

hued leaf. It comes in shades of green-white with pink margin tones and is quite

attractive. The leaves smell quite pungent when crushed.

Height: 12-18 inches

Flowers: white in mid-summer if you can find them very small

Distance to Plant Apart: 24

Sun or Shade: You get the better leaf colouring in full sun but better overall plant health

in part-shade.

Soil: Give this plant damp soils and it will literally outgrow anything around. Dry soilswill slow it down and make it floppy and scorched looking. So you have a choice of an

ugly plant in poor soils or a fast spreading plant in damp or regular soils.

This plant spreads by underground rhizomes and as these break easily, it can be difficultto remove by digging. It is, quite interestingly, resistant to many common herbicides.

Lamiastrum galeobdolan 'Variegatum'

I thankfully sold the farm before this plant escaped its bounds out by the driveway andinvaded the main flower gardens. One of its common names is Yellow Deadnettle. The

flowers are clearly yellow and as other mint relatives, fairly attractive when fresh in early

to mid-summer. I think the other half of the name Dead nettle speaks volumes andwhy anyone would grow a dead nettle is beyond me. I did for a while until it started

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eating other plants in the garden and then I started digging it up. It would make an

excellent ground cover for a barren area.

Those gardeners who admire this plant (and they exist) suggest it is semi-evergreen. I

say that yes, it is frost hardy but that only goes to show how tough it is. They also

suggest it wants good soil and moist conditions. This begs the question why it wasexploding out in the sandy wastelands of my bone-dry driveway garden.

There are two varieties commonly sold in garden centres:

'Herman's Pride' has a more upright growth habit. 'Variegatum' is used as a ground cover

Height: vine like ground hugging but will climb up unsuspecting plants to smotherthem at night.

Flowers: yellow fairly attractive

Distance to Plant Apart: neighbouring countries should do it but 18-24 is common

Sun or Shade: YesSoil: Yes

Ornamental Grass

And here we run right square into the

middle of a modern garden prejudiceand conflict. On one hand are the

proponents of grass in the landscapefor its design effects. On the otherare those who have to control this

stuff.

The key is to pick your battles. Toavoid the real spreaders in the grass

crowd that can make you life not to

mention your back a struggle whenit comes to controlling these plants.

Understand that your climate isgoing to have more of an effect on

grass plants than any of the others in

this book. As an example, Pampas grass (Cortaderia selloana) is invasive in Florida andCalifornia and its razor sharp leaves can be a terrible thing to have to fight in digging it

up and controlling it.

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In my zone 4 garden, Miscanthus sacchariflorus would behave itself for a few years and

then explode across the garden. Its tough root mass was hard on shovels and I bentmore than a few shovel handles digging this plant up for sale in the nursery. And Phalaris

arundinacea or Ribbon grass is one that should never be planted as its green and white

striped leaves are responsible for many a colourful epithet.

Having said that, there are some amazing grasses on the market that are quite gorgeous

but do not paint them all with the same angelic colouring. This short note is only to warnyou that there are thugs in the grass world and if you see one that is reported to establish

quickly or grows well then you might do a bit more research before letting it loose in

a good garden.

Physalis (Chinese Lantern)

I once saw this plant explode from a concrete in-ground container (it developed a crack)

and appeared a few feet outside it. The owner thought it looked cute there and left it.Big mistake. The following season, this plant had spread by underground runner and

seeds invading her entire garden and lawn. Thelawnmower made reasonably short work of the

lawn invader (it merely hid beneath the grass

throwing up shoots all summer) but the garden

had to have a careful and complete digging upand overhaul. She became expert at identifying

and pulling tiny Physalis seedlings.

Interestingly enough, she wasnt amused anylonger and didnt consider it cute.

It is most often grown by gardeners who want todry the attractive lantern-shaped seed heads. Do

yourself a favour and buy the seedheads from

some other foolish person.

Height: 18

Flowers: orange lantern shaped often used as dried flowers

Distance to Plant Apart: why bother setting in two. Give it two years and youll haveenough lanterns to light up your neighbourhood.

Sun or Shade: sun is best if youre desperate but part shade will work almost equally

wellSoil: anything from sand to concrete seems to do it. Not sure about heavy clay.

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Lysimachia

I never met a member of this family that didnt like to spread. Some like the short

ground hugging L. nummularia are more easily

controlled than other species because L.nummularia creeps over the ground and not under

it. Those that spread by underground rhizomes can

be real dogs to control unless you have a 24/7sentinel armed with a razor-sharp, stainless steel

shovel.

I actually like the L. nummularia aurea a gold-

leaved form of the dwarf plant and found that a drysoil controlled it fairly well. A yearly shovel edging

was all it took to control the plant.

Lysmachia punctata is a lover of damp soils andyoull see it or its variegated sport Alexander (left

above) or Golden Alexander sold in gardencentres. At 36 inches tall, its yellow flowers are

quite showy and this plant does very well when

planted in wet soils next to ponds. Does very

well could be interpreted as takes off and invadedneighbouring countries.

Lysmachia clethroides (left below) is theGooseneck Loosestrife and it has excellent flowers

for cutting and drying. Flower arrangers prize thecurled white mid-summer blossoms. I managed tohold this 48-inch plant in one section of garden

approximately two feet across for four or five years

and decided its reputation for spreading wasunwarranted. I moved a small chunk of it into the

main garden where the soil wasnt dust dry and was

deeper than six inches. It took off. I managed to

dig it up in the second year and theres no tellingwhat it might have grown into had I not succeeded

then.

All do well in full sun or part shade and bloom in mid-summer with white or yellow

blossoms.

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Physostegia virginiana

Obedient flower or Dragons Head are two names by which this thug goes by. It is not

obedient except if you turn the flower heads, they will tend to stay in that position (hence

obedient) It is a good garden performer for a big, wild, blowsy cottage style garden butit is a certified thug in a good soil. All the

varieties (possible exception noted below)

behave in a thuglike manner. I once planted a

new variety next to a rose bush in an islandbed where it gave a good display for two years

and then exploded when I wasnt looking. I

spent the next three years digging it out of the

entire bed. Silly me! I should have knownbetter but I have to try these things out.

Height: 36

Flowers: whites and shades of pink or violet

pink

Distance to Plant Apart: 18 to 24 inches

Sun or Shade: prefers sun but will grow well

in part shade

Soil: any place but good, well-fertilized and

moist soils to control its spread

Im told that the new variety Miss Manners is a clump forming plant and not a

spreader. Id have to see it to believe it but maybe

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Polygonum cuspidatum

This plant is sometimes called knotweed or smartweed. Which tells you one thing it is aweed. It also tells you that it is knotty and you arent smart if you plant it (it is smart if it

gets planted)

Height: 48 inches

Flowers: white sometime in early summer



Soil: It really likes damp soil. Put it there and you have to stand back very quickly after

youve backfilled the pot. It comes out of the ground so fast that unwary gardeners have

had ankles broken by spreading shoots.

It spreads by underground rhizomes and these will travel goodly distances over the

course of a growing season.

I note that Polygonum alpinum is a 3 to 5 foot tall, white blooming plant. It thrives in fullsun or part shade and puts on a magnificent show of white blooms. Not overly

aggressive but it does spread by underground rhizomes.

Do not mistake this plant for Polygonatum or Solomons Seal a rather more refinedwoodlander with only slight spreading tendencies.

Sedum Acre

This sedum is a noxious weed, is listed as the same in many provincial and state weedbooks and is still sold by production nurseries by the truck full. It is a gorgeous

fluorescent yellow when in bloom and quite seductive. What they dont tell you is that

each blossom has a gazillion seeds and these are dispersed quite easily by wind or animal.Not only that but any teensy, tiny section of this plant is quite capable of rooting if

detached from the mother plant to form its own colony. The plant is virtually

indestructible in winter cold. It should never be allowed into rock gardens (or other

gardens for that matter)

Height: 1 inch tall

Flowers: fluorescent yellow in early summer

Distance to Plant Apart: 1 mile or 18 inches depending on your sense of sanity


Soil: From sand to rock

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Words to Beware:

Establishes quickly - means in two weeks it will be three feet across Spreading - it will attack you while you are sleeping Invasive comes with its own artillery Easy to grow and grow, and grow and grow Ground cover leaves no plant uncovered, smothers all expensive plants first. Specimen plant - leave it alone by itself

Hardy - requires a personal nuclear device to eradicate

Grows in tough places - so did Genghis Khan A good beginner plant - theyre the only ones whod spend money on it

everybody else is digging it out of their gardens

Will grow anywhere - but particularly in your best garden area ignoring thewaste area you want covered.

Neighbour - as in my neighbour gave me this plant. Unspeakable! Which iswhat normally happens after you discover what the plant is doing to your gardenand you no longer want to see the neighbour, never mind speak to her.

Plant Sale - where neighbours try to charge for their excess hardy, beginnerplants that will establish quickly in your garden and grow anywhere.

I hope you enjoy this Plant Thug ebook. Feel free to write and tell me of your own plant

thug adventures. Ill update and change this book based on reader feedback.

Doug

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