Roundup - how long before I start growing veg safely?

Nice_Username

Hi

I have almost dug my plot having removed the top couple of inches which was covered in thick couch grass.

I want to rotivate it soon to a depth of about 8-10 inches to finish it off nicely but before I do I was thinking about spraying it with Roundup weedkiller as there are still loads of bits of couch grass everywhere and I know it comes back very aggresively, even with just the smallest root part left.

Thing is, I also need to get my early potatoes in soon so I was wondering how long before the soil is safe to plant in?

Also, is there a fast-acting manure that I can buy as I have not had the opportunity to get hold of any horse manure over the winter?

Any advice gratefully received.

olly300

Round up or glyphosate becomes inactive when it comes into contact with soil so you can plant potatoes after the plants you want to kill have died.

However with a weed like couch grass the best removal method if you are not gardening organically is a mixture of spraying with weed killer and digging up the roots.

conradmum

It'll take at least 2 to 3 weeks for the grass to die off, so factor that into your timetable. If you rotavate before the weedkiller has had a chance to get down to the roots and kill them, you'll be stopping the weedkiller from working properly.

It should say on the packet how long to leave it before planting into the soil but this is more to do with leaving it sufficient time to do the job, rather than the soil being contaminated.

Even if your earlies go in late, you can still have new potatoes, just later in the year than normal.