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How long between spraying Glyphosate and the Glyphosate "getting in place" to kill the plant.

My issue is this - I want to make productive use of an area overrun by very well established weeds - and only have 3 days in which to prepare the area and get my weedmat and plants in place. I can't really pull the plants out by hand - the roots are too well established and there are too many of them.

I know that glyphosate takes some time to actually kill the weeds, but I'm wondering if the glyphosate will penetrate the plant within 24 hours such that if I cut the foliage down to ground level (and cover with weed mat) it will "stay dead" and allow me to plant my new plants through holes in the weed mat without overrunning my tender seedlings ?

Glorfindel
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davidgo
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1 Answers1

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Glyphosate is systemic in action - that means it takes about three weeks to kill a plant, but with the added proviso that it's at its most effective as a weedkiller if applied when weeds are growing strongly rather than when they're slowing down because of the approach of Fall, or because the ground is dry and they're short of water. Well established weeds will very likely need more than one treatment, so I'm afraid glyphosate will be ineffective if used in the manner you describe, that is, spraying and then cutting down the topgrowth within 1-2 days, see here http://www.weedkiller2u.com/weedkiller-faqs

If you want to plant out so quickly, the only viable option is to dig out the weeds, complete with roots, level off and then plant.The other point is, if what you're planting are food plants, particularly root crops, there is strong evidence to suggest that, in some soils, vegetables such as carrots will retain glyphosate within their structure as they grow - it won't kill them, but it will be present in the vegetable on your plate, despite the claims of the manufacturers of Roundup that it somehow disappears completely once it hits the soil. In fact, it becomes technically inert, meaning it shouldn't kill new plants put in after application, but may end up in whatever you're growing, particularly if you replant so quickly after application - this is not necessarily important for ornamental plants, but is important if you're growing edibles.

Bamboo
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