How To Remove Marestail, Couchgrass, Bindweed & Other Noxious Weeds

Noxious Perennial Weeds, Such as Couchgrass, Bindweed & Marestail, Are A Gardening Nightmare To Kill & Get Rid Of. Here’s How To Remove Marestail, Couchgrass, Bindweed & Other Noxious Weeds Permanently.

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I see so many social media posts about How To Remove Marestail, Couchgrass, Bindweed and Other Noxious perennials. And I feel for anyone that has them, especially if they are a new gardener, as they are very difficult to get rid of. Sadly, overgrown allotments are often rife with marestail, nettles, couch grass, and bindweed. Allotment committees seem to think it is OK to let new gardeners take over the jungle of crap they are left with and then sometimes chases the new tenant if they don’t make rapid progress. This article shows the best way to deal with the weed control problem, and it’s not the one many people try.

Why Are Marestail, Couchgrass, Bindweed And Nettles So Difficult To Control?

In all of the above cases it comes down to their root system. They all have roots that go deep and are very vigorous. And they will all grow from small sections of root left in the soil. So even if you dig nearly all of it out it still returns from any pieces you’ve missed. And some of the roots go very deep so you need to be a miner too expect to find it all!

Marestail it is worth mentioning is a very ancient plant that produces spore rather than seed. It has a history going back maybe 100 million years. It’s a survivor!

Recommended Ways To Destroy Marestail, Couchgrass, Nettles & Bindweed – How To Remove Marestail etc.

These are the ways I see often see recommended .. they aren’t my recommendations. Mine comes later.

Synthetic Chemical Weedkillers

Garden centres recommend weedkillers. Well they would wouldn’t they, they sell weedkillers and they are expensive. I wouldn’t mind if wed=killers worked, but to be honest they often have a marginal effect and fail to kill all the roots, so within a few weeks the weeds return.

The problem isn’t that the weedkillers don’t work, it’s how they work. They have to be absorbed through the leaves into the stems and translocated to the roots where they kill the roots. If you get the chemical to the roots, in sufficient volumes, it is quite effective. But there’a a big IF.

The problem with plants such as mares tail is that the leaves are small and contain a lot of silica. The silica and small leaves prevent enough chemical getting to the roots, so it fails to work.

Even weeds such as nettles, with big leaves, are hard to kill. Nettles have hairy leaves which prevents the weedkiller reaching the plant leaf surface and being absorbed. It sits on the leaf hairs, looks wet, and evaporates.

And even if you get it to the nettles roots it takes at least one spray a season for several years to kill all the roots.

I don’t like chemical weedkillers for three reasons. They don’t work, they are expensive and they harm the environment. What’s to like about synthetic chemical weedkillers? Nothing as far as I’m concerned in all but 0.01% of cases.

Digging Deep Rooted Weeds

Digging weeds out certainly works if you get every single piece of root out. You’ll need to dig 3-4 feet deep to do it and even then you are very unlikely to get it all out.

You’ll be very fit after digging your plot this deep but it’s not likely you’ll be totally free of weeds. And on the minus side all that digging damages the soil structure and releases carbon in to the atmosphere.

So what’s the point?

Starving Perennial Weeds

If the plant doesn’t get enough sunlight it can’t photosynthesise and will eventually die.

The way I have killed perennial weeds on a field scale is the one that many gardens say doesn’t work. That is to rotovate. Done badly it chops the roots up into small pieces and they all grow again. The problem is worse than before.

But chop them very small, using a high rotor speed and slow land speed and they are obliterated. Chopped so small they cannot grow again. But to do this you really need a tractor mounted rotavator. And you need to repeat it a few times, usually after a couple of weeks, to kill off any root that survives the first time or two.

To achieve success with this you need the right equipment and to be able to access the plot properly with the equipment.

Starving Perennial Weeds Without A Tractor – How To Remove Marestail Etc Permanently

So far I’ve shown you several reasons why killing perennial weeds such as mares tail, Couch, bindweed and nettles is so hard, indeed virtually impossible, or needs heavy equipment.

Now I’ll show you a method that is much less effort and works very well. It’s the one I’m currently using in our food forest which is full of couch grass, bits of bindweed, nettles etc.

What we are doing is to starve the weeds with kindness!

We lay down cardboard on long grass and weeds and cover it with a thick layer of fresh woodchip. the lack of light kills most things INCLUDING the obnoxious weeds. A very few stragglers such up through th deep woodchip and are very easy to pull out by hand without digging.

The image shows a pice of couch I pulled out. It’s thin and was struggling to survive. But be warned, if left for too long it would gain a foothold and the result would be rampant weeds. The key is to remove whatever straggly bits get through every 2-3 weeks. It takes minutes as very little forces through.

Is cardboard necessary? It seems not. We ran out of card and jus spout down 4-6 inch of woodchip instead. The result is just the same. Very few weeds get through.

Does Woodchip Kill the Soil?

How To Remove Marestail, Couchgrass etc.

Some people fear that nothing can be grown in the woodchip and that it robs the soil of nitrogen. I can see why they might think this. But it isn’t a problem.

If we were to sow small seeds, such as carrots, in the woodchip they would die due to a lack of moisture and generally poor conditions. And the surface of the soil could be slightly depleted of nitrogen as the woodchip rots. But as the woodchip rots it is only in contact with the soil at the surface. It takes nitrogen from the soil it’s in contact with but a few millimetres deep it has no impact at all.

There are several crops that will grow in woodchip covered soil. I’ve planted raspberries and they are thriving. So does anything that is transplanted deep sop the root is in contact with the soil. Brassicas and leeks are examples of what does well in these conditions. In fact I’ve added a few perennial kale and they are thriving. And in a month or so (early July) I’m adding leek transplants. They get dibbed in to deep holes and will root into the soil below.

What Happens to the Woodchip?

In the food forest I intend to leave the woodchip in situ. Where it’s deep we might rake it back a bit and decrease the depth. But food forest plants will do fine being planted through it.

On a garden bed I suggest it is raked off after a year and the beds are then treated as normal. For me that means No Dig but for others it will mean digging. That’s a choice for the individual. The raked off woodchip will be partially rotted and I’d suggest composting it fully or moving it to another area to be reclaimed. If composting I’d use the Johnson-Su biodigester technique that I detail in the linked post.

The Weed Seed Reinfestation Danger

Where weeds such as Couchgrass have been well established you need to watch out for reinfestation from seed. It’s why I prefer No Dig, it makes it easier to control.

The other danger is reinfestation from adding plots. It’s no good clearing your plot to let the roots creep in from an adjoining plot. If they will not clear there area then create a barrier such as a woodchip path where you can spot the problem before to reaches your beds.

Reinfestation isn’t good if you want to follow my How To Remove Marestail advice!