What would Jeff Gillman do? Roundup and my garden

– Posted in: Miscellaneous

When I was first approached about having Jeff Gillman, author of The Truth About Organic Gardening, write a post for my blog, I several ideas that I presented to Jeff. He was willing tackle all of them! I decided to relate how I have used Roundup in my garden, and let Jeff comment on my practices, for the education of us all. Here goes…

I have many kinds of invasive plants growing on our acreage. I also have many types of trees and shrubs growing here which, while not invasive (indeed, many are native), are weeds when growing in my cultivated garden. In the course of reading Sara Stein’s Planting Noah’s Garden: Further Adventures in Backyard Ecology (1997), I became persuaded that Roundup, used as she described, was a responsible way to take care of these problems. Below are some excerpts from the chapter on controlling weeds that indicate what types of points she made.

Jeff: I tend to agree that Roundup is useful in these sorts of situation. And by Round-up I mean glyphosate (that’s the primary active ingredient in Round-up) without any extra bells and whistles (all kinds of other active ingredients may be added – I don’t like them because they make the spray more toxic and may make the glyphosate itself work better – or worse).

“Cutting down a [woody] plant is the physiological equivalent of pruning it to encourage new growth . . . To finally kill the plant, the sprouts have to be cut repeatedly until the roots are depleted of stored nutrients and the plant starves.”

“Glyphosate adheres to soil particles, so it does not enter groundwater. Soil microorganisms rapidly break it down to phosphate, a plant nutrient . . . and glycine, an amino acid that . . . is further broken down into nitrogen, carbon dioxide, and water.”

“Glyphosate is a nonspecific herbicide: it kills every kind of vegetation. For this reason, and despite its low toxicity to animals, it should be used only in the most precise manner to avoid injuring any but the target species.”

Jeff: Basically true – but it can be pretty darn toxic to aquatic animals such as frogs – not the glyphosate itself mind you, but rather the things it’s mixed with such as soaps.

“Roundup . . . [is] sold in both diluted and concentrated form. Choose the concentrate; it can be diluted in water to the percentage most effective for the control method you’re using.”

“In most cases, invasive trees and shrubs can be killed by brushing a small amount of herbicide onto the freshly cut surface of the stem or trunk. This method, called cut-surface application, uses the least possible chemical and delivers it precisely to the target plant.
* The chemical must be applied to a fresh wound . . .
* Treatment is most effective toward the end of summer . . .
* Use a concentrated solution . . . Those experienced in cut-surface application have found a 20% solution (1 part concentrate to 4 parts water) sufficient for most species. You need only a very small amount: 1 cup (8 ounces) is enough for a weekend’s work.
* Prevent spills by keeping the mixture in a jar with a screw top that you can close when you’re not using it. A rubber cement jar, sold in art stores, makes an excellent container. The screw top has a brush that’s adjustable in height so the bristles are moistened but not dripping.”

Jeff: This is a way that glyphosate is often used and it is quite effective. But once again, be careful to use glyphosate without the extra active ingredients.

Our property was neglected for several years before we took ownership, and there are some maple saplings growing in lilac thickets that kept resprouting after I cut them to the ground. We have a large patch of Japanese bamboo (Polygonum cuspidatum) which I try to keep contained by mowing. However, when I found it growing in new locations I became concerned and had wanted to treat the new infestations with Roundup.

Jeff: For your issues I think Roundup would be fine as long as you’re careful of drift.

Reading The Truth About Organic Gardening” made me think about that container of Roundup. I still have problems with tree saplings and Japanese bamboo, but it had been a couple of years since I’d done anything about them.

The container of Roundup (16 fluid ounces, 18% glyphosate) and the rubber cement jar were both in a cabinet in the laundry room, highest shelf, way in the back. Dusty, even. How old was it, anyway? There is no expiration date on the Roundup container. Does that mean it is good forever, or that they want to keep you guessing? The rubber cement jar is labeled “50mL glyphosate (Roundup) 200mL water POISON” in my handwriting, with a hand drawn yucky face. The jar is about three-quarters full, and when I move it I can see nebulous stuff swirling in the bottom of the liquid.

Jeff: Here we have some problems. Do not ever store mixed up pesticides for longer than a few minutes – if you do you will end up with gook that is either useless or dangerous and, worse than that, you won’t have the label in a readily accessible location. This is particularly important because the label includes information on how to treat if there’s accidental contact with the pesticide. Without that information you may seriously delay treatment.

Pesticides that aren’t mixed up can usually be stored for a few years (4-6) before they should be either used or disposed of. Simply using a pesticide (following labeled directions) is often the best way to be rid of it. Pay attention to the directions on the label for how to discard particular pesticides. Some can go into the garbage, some can’t.

The solution in the rubber cement jar represents the second or third mixture I made. I think at least once I got rid of the old stuff in the jar and made a new solution, but I have no idea how I got rid of the old stuff. It says right on the container not to contaminate water, so hopefully I didn’t spill it down the drain. It does say to wrap a partially used container in several layers of newspaper and discard in the trash. But I wasn’t about to throw out my expensive rubber cement jar, and back then I was pretty sure the concentrate in the original container was still good, so I wouldn’t have thrown that out, either. Maybe I put it in an empty jar and screwed on the lid, wrapped it in newspaper, and threw it in the trash. Maybe I poured it on our dirt (originally gravel) driveway.

Jeff: If you followed what was on the label then you did the right thing – the only problem that I have is the rubber cement jar. Sure, it was fine for application. But it really shouldn’t have been used for storage. Applying the pesticide to your driveway to get rid of it isn’t a terrible idea. Once again, applying the pesticide is a legitimate way to dispose of it.

So how old is this stuff, anyway? It just so happens I am a bookkeeper at heart, and have been using financial software (first Manage Your Money, and then Quicken) for years. Consequently I can tell you with authority that I bought it on May 8, 1999 for not quite $15. Gosh, I didn’t think it was that long ago! But I’ve only bought the one container of Roundup, so it must be true.

So, if I want to get back to eliminating tree seedlings and keeping the Japanese bamboo from establishing a foothold in new locations, is the old Roundup concentrate still good? Is it still considered the best solution to these kinds of problems? And is it a responsible solution to multiflora rose, Tartarian honeysuckle, and autumn olive?

Jeff: I think it’s time to get rid of it….I’d get rid of the problems that you mention with a combination of glyphosate and triclopyr (which works much better on some weeds than glyphosate does). I know that I above I recommended using just glyphosate, but when you start dealing with woody/shrubby weeds the added triclopyr will really help. I believe that you can buy this combination as Roundup brush killer (or something similar). But check the active ingredients to make sure.

Are there any pesticide skeletons in your closet? What’s your favorite way to get rid of invasive shrubs? I’m always looking for a better way to tackle this problem.

About the Author

Kathy Purdy is a colchicum evangelist, converting unsuspecting gardeners into colchicophiles. She would be delighted to speak to your group about colchicums or other gardening topics. Kathy’s been writing since 4th grade, gardening since high school, and blogging since 2002.

If winter is slumber and spring is birth, and summer is life, then autumn rounds out to be reflection. It’s a time of year when the leaves are down and the harvest is in and the perennials are gone. Mother Earth just closed up the drapes on another year and it’s time to reflect on what’s come before.

~Mitchell Burgess in Northern Exposure

Comments on this entry are closed.

Michael Peterson March 22, 2013, 2:44 pm

Organic alternative to Roundup

Hi – My name is Michael Peterson and my wife and I have invented an organic herbicide sprayer that will reduce the use of Roundup.
If you have an opportunity, please use the link below to look at our invention (the Garden HotShot) and let us know what you think.
Michael and Bonnie

Mike August 26, 2008, 4:27 am

Great review and a tactful way to examine using Roundup. I too garden organically, and take a natural health lifestyle very seriously. But I also use Roundup at times around our property.

We manage almost 10 acres, and garden on about 1. The nature of poison ivy and other invasive plants can be very difficult to manage, especially when there is one person doing most of the work!

And yes, there are many alternatives to avoid using any herbicide at all, which we do for the garden most of the year. The good old fashioned hoe works wonders too.

But for perimeters and difficult spot problems, using a little glyphosate infrequently can be very effective.

To many of those who are so critical of someone considering use of Roundup, I would say, #1) They have probably not tried to manage a large acreage or property and done so organically for the most part, and 2) There are far worse products being used on lawns and suburban landscapes every day.

My goal is to not use any synthetic chemical application at all, but I believe limited application of Roundup can be done safely, at least until I can afford to pay a few people to help pull weeds on several acres.

Cynthia July 31, 2008, 12:26 pm

I really enjoyed this article. I garden entirely organically except for my recent love of Roundup. The only thing that makes me feel better about the product is how it quickly it breaks down once it contacts the soil.

My husband I and purchased a property with a large colonial style garden. The house had been negleted for several years. At first I was attempting to remove all the weeds from the pathways and beds by hand. I finally gave up and bought the Roundup concentrate and a small pump sprayer. Using the utmost of caution during application the weeds are now under control and I haven’t harmed any benifical plants.

It’s encouraging to know others interested in organic gardening don’t see Roundup as totally evil. While I don’t enjoy using it, I don’t want to pull out my formal garden either since it’s one of things we loved about the house.

shannon April 11, 2008, 1:17 pm

I have to admit that I love Roundup, although in every other respect I am an organic gardener through and through. I also have to admit that a lot of the things i use it for are things that I planted: crown vetch that got out of control, akebia that got out of control, English ivy that got out of control. Don’t plant invasive species! Some of them were there when I got there, mainly Lonicera japonica.

I have used the paint brush method recently and I don’t know yet if it’s working because I haven’t been back to my garden in a couple of months, but I’m glad to hear it works for other people.

Roald April 2, 2008, 10:58 am

I have a lawn infested with “wild garlic”. If I use Roundup on this I assume the grass will die and I will need to replant. Short of digging up the whole lawn and starting over are there any suggestions or other options I might try?

bill March 28, 2008, 9:27 am

In my experience you could dispense with the roundup in this situation and achieve the same result. I just scalp the grass by mowing at the very lowest setting, then remove the grass by running a shovel blade an inch or so below the surface. St Augustine has very shallow roots. This method won’t work though if you have bermuda grass.

Bonnie March 27, 2008, 11:22 pm

Great info, thanks for initiating.

I recently used roundup in transforming two large areas of St. Augustine into native plant beds. I sprayed roundup on the St. A, left it for about two weeks, then tilled it under to put the organic material of the dead grass back into the soil. Compost, 4 layers of newspaper and 4 inches of mulch later and I have not seen hide nor hair of that St. Augustine.

Beth Botts, Chicago Tribune March 26, 2008, 2:11 pm

I have a small, quite urban yard, and although I garden organically in most other respects I do use glyphosate occasionally and sparingly for incorrigible aggressive plants. After a very expensive tuckpointing job, we have been using glyphosate to fight the Boston ivy that wants to swathe the apartment building. Applying it repeatedly with a brush to the cut stumps seems to restrain the ivy, though I can’t say we’ve exterminated it. But this is standard garden-center Round-Up; maybe the stronger concentrate would be more deadly. Not that the regular Round-Up is without perils. An attempt to apply it to creeping Charlie in the lawn — very meticulously, leaf by leaf, with a child’s paintbrush — killed a big patch of grass that had to be reseeded. No more glyphosate in the lawn!

Pam/Digging March 22, 2008, 6:13 pm

I use Round-Up as sparingly as possible, but I do find it indispensible in my fight against two persistent weeds in my yard, as well as against Bermuda grass infestations, which I’ve never known to be completely killed by solarizing.

Carol, May Dreams Gardens March 22, 2008, 6:49 am

I’ve used Round up in the past but am currently using Perfectly Natural Weed n’ Grass Killer. Is it any safer? I’ve got to have something to kill the thistle.

kate March 21, 2008, 5:49 pm

So far I haven’t had to use Round-Up in my garden, but then I garden on a small property. My neighbour loves Round-up ever since she covered her entire back property with pea gravel. She sprays the entire yard with Round-up – I guess it is always at the ready. I worry about what else is being affected besides errant grass.

jodi March 20, 2008, 10:16 pm

I ran an experiment last year to see which would be more effective: solarizing a patch of goutweed (Aegopodium) with black silage plastic from a friendly dairy farmer, or applying glyphosate to it late in the season. I had two sections of this annoying, useless plant running towards my horse’s paddock, so decided to divide the area into two sections and try the two methods. If spring ever comes, I’ll let you know how it worked out.
By the way, I got both Jeff’s books via Amazon.ca and am well into the ‘remedies’ volume…highly recommended, and I’ll be writing about them at some point soon. He’s my new hero…

vonlafin March 19, 2008, 3:51 pm

I use roundup for control of a trumpet vine that I removed years ago. It seems to work, but every year there are new sprouts to deal with.

Diana March 18, 2008, 11:12 pm

Kathy – I fess up – we use Round up on the poison ivy – my husband’s very allergic. But I usually brush it on sparingly. Hey – my “prize” book came today — thanks again for hosting the organic contest. I’m eager to see what else Jeff has to say – I loved the forward – that’s as far as I’ve gotten today!

Jeff Gillman March 18, 2008, 7:00 pm

Hi Bill

Since you are (hopefully) only spraying a few plants and not directing the spray towards the lake it should be OK. However, if you find yourself using large quantities right at the edge of the lake then perhaps you should try something besides chemicals.

Using a brush application is a good way to prevent drift and is very appropriate if you’re near a lake.

bill March 18, 2008, 6:15 pm

I live on a lake. Well, on the shore of a lake. Is it okay for me to be using Roundup?

bill March 18, 2008, 6:02 pm

I have it mixed with water in a spray bottle in my garden shed next to a bottle of the concentrate. You are right – it’s a dumb thing to do. I don’t have it labeled at all and nobody but me knows what it is.

Gail March 18, 2008, 5:18 pm

I confess to using Roundup on Bush honeysuckle and poison ivy…I usually cut the stems and then apply the roundup with a brush.


Mr. McGregor's Daughter March 18, 2008, 4:07 pm

I have been using Sarah Stein’s method for several years now to get rid of sprouts from Boxelder & Buckthorn stumps. I’ve also resorted to Roundup to get rid of the Bindweed infestation in my lawn. My method of application is slightly different though. While wearing heavy chemical resistant gloves, I dip a Q-tip in the stuff, then dab it on the leaves of the Bindweed or directly on the cut surface of the woody plants. Seems to work well for me with no drift problems.

Annie in Austin March 18, 2008, 12:56 pm

So far I haven’t had to use Roundup, but mentally reserved the right to buy some if poison ivy invaded. Thanks for the information Kathy and Jeff.

Annie at the Transplantable Rose

wiseacre March 18, 2008, 12:50 pm

I’m known to be ‘organic’ so when I suggest using Roundup occassionally I tend to shock people. It has it uses at times when nothing else is practical.

Japanese Bamboo or more commonaly known around here as Japanese Knotweed is a nightmare plant. I cringe when ever someone askes me to get rid of it. I’ve found the only solution is using Roundup and that takes multiple applications during the season.

I have controlled it using heavy black plastic but that can take a couple seasons. I’ve seen it come back after soil and subsoil was removed to a depth of 5 feet around a foundation of a house. Crushed stone was put in and concrete poured over it for the floor of a greenhouse. It grew out from under the sides and through the stone foundation into the celler. Any root left at all is a whole new bed just waiting for you to turn your back for a moment. It’s the cockroach of the plant world. Sometimes you just have to go with a herbicide like Roundup and get to the root of the problem.

Another use is killing Posion Ivy. I’m not going to fight that stuff by any other means. One bad case was all I ever needed.

Limited and careful use of Roundup is a sound method of controlling some nasty plants.

Did you know that the young shoots of the Japanese Bamboo are edible? But there are not enough survivalists and edible wild plant eaters around to use as a control.

David March 18, 2008, 11:53 am

Brilliant thread, Kathy!
Thank you so much.

Jeff Gillman March 18, 2008, 10:24 am


That may work … or it may not. The problem with your technique is that the leaves may get warm very quickly. When they get very warm they’ll die. And when they die they will no longer take up the glyphosate — which is the stuff that kills the roots! Roundup needs to be in contact with healthy leaves for at least a few hours before it’s taken up — if the leaves aren’t healthy the Roundup won’t work properly.


mss @ Zanthan Gardens March 18, 2008, 10:14 am

Here’s my confession: I have poison ivy and bindweed in my yard. I have used Round-Up but I do so as follows. I gather up as much of the vine as I can and stuff it into a plastic bag. Then I spray the Round-Up into the bag and tie the bag’s open end. I hope that the heat will help kill the plants and that the Round-Up will kill the roots systemically.

I do have a large population of toads, lizards and the occasional small snake.

Rurality March 18, 2008, 7:46 am

That is a *really* good point about not storing without the label information. I wouldn’t have thought of it!