I spent the last couple of hours digging out grass from our vegetable garden. The roots go under the planks of our raised beds up into the beds. I have to dig down both inside the beds and outside. What I want is a barrier that kills opportunistic roots as they try to cross or penetrate the barrier. I have in mind some kind of tough fabric that has microencapsulated glyphosate or some such throughout. As the roots try to pass through/around the barrier they put pressure on the capsule and burst it, the herbicide is released, and the roots are stopped.
Please tell me such a product is out there somewhere and is affordable, effective, and has only a positive effect on the environment! And if it’s not, please develop it and give me a royalty. Thank you.
It’s called masonry . The walls of the bed go down 16" below the soil line and if necessary there is a French drain leading out of the bed below that level. The blocks are hollow, overlapping, and cement-filled with vertical rebar.
Remember, roots grow all directions. That includes veggies that will grow toward your glyphosate barrier. The simple solution would be some metal dug in to the depth of the roots you are fighting. I personally just use heavy landscaping fabric between beds.
Glyphosate gets deactivated quickly upon contact with the soil. It has to be absorbed through the leaves to be effective (can be absorbed through stems, but probably much slower through wood than through green tissue).
I used to spray glyphosate along the perimeter of my raised beds to keep grass and other weeds from creeping into them.
Yea I’d recommend some sort of deep border, or get a tiny stirrup hoe or something less back-breaking to till the border. Maybe create a periodically worked “No Man’s Land” with mulch along the edge of all beds.
Around here we have lots of Timothy. It’s runners will grow as much as 6 ft in any direction. I’ve found a tilled and sheet mulched or cover cropped swath about 6’ wide is sufficient to keep it at bay, but it needs to be renewed annually. My strategy for dealing with it leans toward planting densely and in ever expanding patches. Amazing how much work can be undone in not much time as things are reclaimed by the grass. On the plus side, battling it seems to really improve the soil. On the downside, it also tends to create quite the oasis for voles. Then again, even they have their upside (grinding teeth currently at the utterance of the word vole) since they till and nourish the soil a great deal with their vile ways
is the gras actually spreading into your beds from the roots growing under the planks? (like quackgrass)
Or is it just a pain to remove roots that grow deep and below the planks?
the problem with your proposed barrier is, that it would not be selective. (it kills both the weeds and your plants/vegtables)
This lack of selectiveness is a major problem with herbicides. And the reason why the combination of roundup and roundup-ready crops is so populair.
my preference would be to have a groundcover or gras growing next to your beds that spreads by aboveground stolons, instead of belowground roots. Those are easily deterred by a simple barrier.
Things that spread by deep roots, (primocane raspberries and quackgrass for example) need a deep dug in, impermeable barrier to stop them.
I agree there’s a problem with non-selectivity, but the same issue exists however the herbicide is delivered. And it would be quite feasible (i think) to have the encapsulated herbicide applied to one side of a barrier. I was thinking of the situation with landscape where grass (such as quack grass or timothy) sends out runners that eventually pierce the fabric.
It’s true as @anon89542713 says that roots grow in all directions. So what is needed is a dose that just stops the growing point of the root - doesn’t get absorbed into the plant.
Sigh. The devil is always in the details. Still …
. The walls of the bed go down 16" below the soil line and if necessary there is a French drain leading out of the bed below that level. The blocks are hollow, overlapping, and cement-filled with vertical rebar.