By Skip Richter
are wimps. Just swat at them with a hoe or cover them
with a few leaves and they wither and die in a
heartbeat. Others require a little more careful digging
or perhaps a squirt of a little herbicide to take them
out. Then there's bermudagrass and nutsedge, the weed
world's dastardly duo.
If you are putting in a
new garden, it is far better to eliminate any persistent
perennial weeds before you begin to plant, even if it
means delaying planting for a while. If you already have
a garden in and these two "weeds from Hell" have
invaded, your task is more difficult and your options
are more limited. These perennial weeds can turn a
pleasant gardening experience into a Sisyphean task as
they keep coming back again and again, sentencing you to
a summer of hand-to-weed combat.
These two weeds
may well be responsible for more sweat, tears, profanity
and exasperation than all other weeds combined. If you
have been battling these unwelcomed invaders to little
avail I have good news. They are not immortal or
invincible. They can be controlled, but the battle is
not for the faint of heart. Armed with a few tips and a
proper mind set you can win this battle.
begin with a little psychological adjusting. Remember in
the movie Patton when the general paces back and
forth across the stage at the start of the movie telling
the new recruits what they are in for and helping them
understand the proper perspective they need in order to
win? OK that is what I'm up to here.
Get in touch
with your inner Terminator. Be ruthless. You can never
feel sorry for a suffering weed or take a break from the
battle. Never let 'em up for air. Hold 'em under until
the bubbles quit coming out! It's either you or them and
by golly it's gonna be you! That garden belongs to you
and you won't rest until every single weed sprout and
seed is dead, muerto, history, kaput,
Two rules of winning the war on weeds
are consistent effort and getting an early start. The
problem with most attempts at managing these weeds is
that we gardeners tend to fight them a while and then
let up. Once they have a chance to get some green leaves
up in the sunshine for a few weeks they have replenished
their reserves and we basically get to start over.
Remember, never let 'em up for air.
This turfgrass and
pasturegrass has a serious problem with understanding
the concept of borders or respecting our opinion of
where the lawn stops and the flower bed begins.
Bermudagrass spreads by above ground stolons, below
ground rhizomes. Common Bermuda and some varieties also
produce seeds. It can survive drought and thrives in sun
and moist, rich soil conditions.you know, like your
garden. Here are some strategies for managing this
This option is no
fun, but can be effective when the infestation is minor
if you start early in the season so as to not allow the
weed time to spread very far. You just need to stay at
it. When a sprout appears, use a spading fork to lift
the soil so you can get as much of the underground
rhizomes as possible. Pace yourself and give the task
just a little time each morning in the early hours when
it is still reasonably cool out.
Rototilling or plowing in the summer
exposes the rhizomes to the drying sun and forces the
plants to use stored energy to regrow. This must be
repeated frequently many times to have a desired effect.
The minute it starts to grow, till it again.
tillage is hard on the soil, breaking down structure and
burning up organic matter, but this can be fixed later
with additions of compost. I have seen a field of
Bermuda turned into a peach orchard in this way. At the
end there were still a few living remnants of Bermuda,
but the vast majority was destroyed. If seeds are in the
soil they will still be viable and apt to return.
Some gardeners have had limited
success with vertical barriers into the soil to keep the
rhizomes from moving in underground. A barrier is
basically an underground wall to block out the
The barrier material needs to be
impervious to the stolons and able to last for a long
time underground. Thick plastic and weed barrier fabrics
can work if they extend at least 8 inches or more deep.
It helps to angle the top of the "wall" a little toward
the garden side to direct stolons growing inward from
the outside upward or sideways rather than down under
I think barriers are among the least
practical options. It is a lot of work to trench
completely around a garden and install a barrier. The
garden has to be pretty much bermudagrass free to begin
with. You will still need to defend the border of the
garden as the Bermuda stolons will try to creep in over,
and if not deep enough, under the barrier.
I have had fair success holding
bermudagrass at bay with a paper mulch. The basic
technique is to cut the weeds down close to the soil
with a mower or weedeater. Then wet the soil thoroughly
and cover the surface with newspaper 6 to 8 sheets
thick. Overlap the newspaper as you lay it, making sure
the soil surface is completely covered so no light
reaches the ground. Wet the newspaper as you lay
sections to help it "stick" down. Then cover with a
mulch of leaves, pine straw, grass clippings, or
If you see bermudagrass peeking through,
it will be because there was a hole or gap in the
newspaper. Just pull the top off of the plant and patch
the hole with a section of newspaper, wet it and cover
with the mulch. You can set transplants through the
paper but bermudagrass will find the holes, requiring
some hand pulling around the base of the plants.
I have not kept at this technique for an entire year to
see if it has long term effects in controlling
bermudagrass, but it does reduce it a lot and makes an
otherwise infested garden patch bearable for the season.
Perhaps a reader has given this technique a more long
term try and can offer more light on its success.
This may be the best
technique of all for managing bermudagrass. There are
many types of landscape fabrics on the market used as
groundcovers in nurseries or as weed block in ornamental
landscape beds. Experiments at Boggy Creek Farm, an
organic produce farm in Austin, have shown these fabrics
to effectively eliminate bermudagrass if left on the
surface for at least a year.
Purchase a wide
section of the fabric and place it over an area where
you wish to establish a garden or a section of garden
plagued by bermudagrass. Secure the edges with pins
provided by the product manufacturer, bent sections of
coat hanger or bricks. Don't put weights or pins
anywhere except the edges. You can cover the fabric with
some leaves if you don't like the look of the black
Give it an entire year or more. When
you remove it, the Bermuda will have died trying to grow
in the warm moist conditions without sunlight to produce
life sustaining energy. The only Bermuda you will see
after removing the cover is perhaps some seed that lands
in the area or runners creeping in from outside the
You can use the technique to
recapture lost ground a section at a time until the
garden is yours again!
Glyphosate (Roundup, Green Light Com-Pleet and Kleenup)
and several other weed control compounds are quite
effective in killing bermudagrass, but such general
herbicides will kill other green plants the spray
contacts. Glyphosate breaks down quickly so you can
replant within 10 days to 2 weeks. There are also
ingredients selective for grassy weeds that don't pose a
threat to most other plants. Two examples are sethoxydim
(Poast) and fluazifop (GreenLight Bermudagrass Killer,
Grass-B-Gone, Ornamec and Fusilade).
these herbicide ingredients are most effective on
actively growing bermudagrass. On dormant or
drought-stressed bermudagrass they are not very
effective. Therefore, you will need to wait until grass
resumes vigorous growth for it to be an effective
control. Repeat applications are usually needed as there
are always a few weeds that escape or seeds that
In order to avoid damaging
plants while minimizing pesticide applications in the
environment, I have devised a weed wiper that is simple
to build and very effective. It allows you to control
weeds coming up here and there among desirable plants
without getting virtually any product on the soil or
Purchase one of those "grabber"
devices used to reach a jar off of a high shelf. They
usually have either suction cups or rubber grips on the
end that pinches closed and a squeeze grip handle at the
other end. Their length is just right for reaching to
the ground while you stand upright. That's right, no
Take a small kitchen sponge and cut it
in half. Use a small bolt, washer and nut to attach the
two sponge pieces to the pinchers. It may be necessary
to drill a hole through the pinchers depending on the
particular product you buy. Then mix a strong solution
of glyphosate, fluazifop or sethoxydim in a squirt
bottle and wet the sponge. Use the wet sponge to squeeze
and wipe the weeds, taking care not to contact desirable
plants. It is easy, puts virtually no pesticide in the
environment and it works.
Nutsedge, often called "nutgrass," is really not a true
grass, but instead a member of the sedge family. Its
proper name is nutsedge or for you Latin lovers,
Cyperus esculentus (yellow nutsedge) and Cyperus
rotundus (purple nutsedge). It is closer kin to
Papyrus (used to make the ancient writing paper of
Egypt) or the ornamental Umbrella sedges, than to true
grasses like crabgrass, St. Augustine or bermudagrass.
This African native plant has spread throughout the
New World. Because of its ability to thrive and persist,
most gardeners and farmers would agree that to know it
is to hate it.
Can't Beat 'Em? Eat 'Em!
The species name esculentus means edible and yes you can
eat the tubers or nuts of yellow nutsedge which have a
slightly sweet, nutty or almond-like flavor. The tubers
of purple nutsedge are too bitter. There is even a
cultivated variety of yellow nutsedge Cyperus
esculentus var. sativus that produces larger tubers.
This plant despised by us gardeners is known in various
parts of the world as Chufa, Earth-Almond and Tiger
Ancient Egyptians loved Chufas. In fact,
archaeologists examining the opened tombs of Pharaohs
have often found a small quantity of mummified Chufas in
"easy reach" of the corpses! Now, I've heard of being
buried with your family pet, but being buried with your
"nutgrass" is taking things a bit too far!
Spain and some other countries, the drink Horchata is
made by mixing the ground tubers with sugar and water,
to create a milky liquid.
I once ordered and grew
some Chufa Nuts (please don't tell anybody) in my garden
and although they grew, they weren't very impressive to
the palate. They have a distinct almond flavor, but are
very "woody" in texture. After a while you give up
chewing and remove a bit of sawdust from your mouth!
Our own beloved yellow nutsedge is the same genus
and species but a different variety. Its tubers are
smaller and scattered out further from the plant - a
trait which improves its survivability (and weediness!).
Know Your Enemy
Nutsedge tubers are
produced on rhizomes (underground stems) that grow to a
depth of about 12 inches. Each tuber has a number of
buds on it, a fact which leads to its tenacity. When one
sprouts up into a shoot and you chop it off another will
grow to replace it, as many as 7 to 10 times!
Researchers indicate that the tuber uses about 60
percent of its reserves sending up the first shoot and
about 20 percent on the second shoot, but if you quit
chopping after even the fourth shoot emerges and give it
some time to grow it will replenish the stored energy
and you get to start all over again. Remember the
General Patton speech?
By early May a tuber
allowed to grow unchecked will already be forming side
tubers on its rhizomes. Each side tuber forms a plant
and soon is sending out its own side tubers. When a
nutsedge shoot reaches the surface it forms a basal
bulb, from which grow roots and more rhizomes with new
tubers at their ends.
The tuber's skin contains a
chemical substance that inhibits sprouting. Soil
moisture "washes" this inhibitor off of the tuber
allowing it to sprout. This is one reason why the plant
thrives in a wet area of the lawn or garden and
proliferates during wet spring seasons. Some tubers
won't sprout in a given season. This is why it can
appear that you've killed every plant by late summer or
fall and then find an even greater infestation the next
One tuber under moist sunny conditions
can eventually form a patch 10 feet or more in diameter.
In one year, under ideal conditions the outward growth
from one tuber has the mathematical potential to produce
1,900 new plants and 7,000 new tubers. Now you can see
why it's so tough to control! If there is any good news
it's that they tell us that individual tubers do not
last longer than 3 years (thanks a lot, right?).
Depleting Plant Reserves
If you continue to
remove the new plants before they have a chance to
replenish the reserves you can eventually starve and
kill them. In order to do this, remove nutsedge plants
before they have 5 or 6 leaves. This means eradication
of any visible plants a minimum of twice a month. Up to
that stage new side tubers have not yet had time to
Chop, Dig and Hand Pick
chop the tops off repeatedly and consistently although
that is probably the least effective option for managing
this weed. Digging out the tubers is better although it
is pretty labor intensive as most readers already know.
Spading or rototilling and picking out the tubers
that surface is also helpful, but many get buried in the
process. Like other digging methods you will have to
stay at it faithfully for a season or two if it is to be
tubers or using the wiper device described previously is
another way to wear the plants out. Herbicide products
will not eradicate nutsedge in one or two applications,
but, if done correctly and at the right time, will
reduce the infestation and force the surviving tubers to
use energy reserves to send up new growth.
Products containing glyphosate can be effective as can
the natural product pelargonic acid (Scythe and Quik
Weed Killer). Pelargonic acid doesn't translocate down
into the weed like glyphosate but rather burns the top
back, forcing the plant to use reserves to try and
regrow again in an effort to survive. Halosulfuron
(Manage) is labeled for use in turf areas and
translocates down providing fairly effective initial
control. Imazaquin (Image) is also labeled for sedge
control in turf but is not as effective as halosulfuron.
Repeat applications will be required with all products
in order to maintain control.
If you choose to
use an herbicide don't wait until the plants are fully
grown. You can kill the tops at that stage but the plant
will not move the product down to the tuber to kill it,
so your spray will only have a temporary, cosmetic
effect. You need to spray the new plants before they
have about 5 leaves as they are still storing
carbohydrate reserves in the tubers at this early stage.
Thus the spray has a better chance of killing the tuber
or at least weakening the plant significantly.
matter which method you use, chopping, digging, or
spraying, in order for control to be effective, it must
outlast the tuber's ability to regenerate, or an
herbicide product must translocate down and kill the
tuber. Also remember that at any time there are going to
be some unsprouted tubers which will appear later.
Mulching? You bet!
When a nutsedge shoot
emerges, it pushes through the soil with a protective
sheath around it much like an awl punching through
leather. Once it reaches the light the protective sheath
opens up and the leaves fold out to catch the sun.
Before it reaches the light it can punch through
almost anything. It laughs at the paper technique
mentioned for bermudagrass. It pierces thick black
plastic. I've even seen it push through a new asphalt
parking lot! After it is exposed to light it opens up
and can't punch through anything.
fabrics sold as groundcovers vary in their ability to
block out nutsedge. Woven fabrics are not very effective
but the nonwoven spunbonded polypropylene products have
performed quite well in university trials. The emerging
nutsedge shoots have trouble punching through the
tangled mat of fibers in these groundcover fabrics.
Dupont Typar 307 and 312 (3 oz. per square yard weight)
rated the most effective in a university trial.
These fabrics are usually pinned down to the soil
tightly which is fine for nursery and landscape beds
where you are dealing with "normal" weeds. Experience at
the organic farm mentioned earlier showed that if a
standard type of groundcover fabric was held down by
soil over the fabric or any weight holding the fabric
down firmly the nutsedge could punch through. If on the
other hand it was allowed to float on the surface and
only attached to the soil at the sides the weed could
not punch through the loose cover.
allow water to move through. Thus the nutsedge tubers
sprout beneath the fabric during the warm days of summer
and starve to death trying to reach light (remember we
must have no mercy!). Sections of nutsedge-infested soil
covered with fabric (not weighted down) for about a year
have showed no nutsedge regrowth after several years now
since the fabric was removed.
The loose landscape
fabric technique is in my opinion the best way to manage
nutsedge in a vegetable garden. You just have to be
patient and leave some areas fallow for a year while the
fabric does its work. I suggest laying a thick layer of
leaves on the soil surface and then laying the fabric
over the top. The leaves will decompose so when the
fabric is removed the soil can be tilled up and planted.
Then move to a new area the next year. Experiment with
this technique to see how it works for you and if a year
proves to be long enough to kill the tubers or if the
tilling brings up some deep buried tubers that did not
yet sprout. I think you'll find it to be very effective.
Should some nutsedge show its ugly head you know what to
Never Give Up or Let Up!
Nutsedge, although a tough, formidable foe, is not
invincible. With diligent, determined effort it can be
controlled quite effectively in the home garden and
landscape. This weekend rent some old war movies to get
in the right frame of mind. Then go out there and storm
the enemy in an ongoing consistent blitzkrieg until you
regain your lost land.
I'll leave you with these
words from the immortal coach Knute Rockne, as they are
fitting for the task at hand:
"We're going inside
of 'em, were going outside of 'em, - inside of 'em,
outside of 'em!, - and when we get them on the run once,
we're going to keep 'em on the run, and we're not going
to pass unless their secondary comes up too close!
"But don't forget men, when we get 'em on the run,
we're going to go, go, go!, and we aren't going to stop
until we go over that goal line!, and don't forget men,
today is the day we're going to win!
lick us, and that's how it goes! The first platoon of
men go in there and fight! Fight! Fight! Fight! Fight!
"What do you say men!"
Seed head color
to sharp tip
several along each rhizome
reddish to purplish-brown
pale or light green
to sharp needle-like tip
one at end of