http://www.environmentalhealthnews.org/ehs/news/roundup-weed-killer-is-toxic-to-human-cells.-study-intensifies-debate-over-inert-ingredientsmaybe worth reading the above link before using roundup !!!!! then make your mind up . Covering with plastic etc, will kill off all top growth , and leave you with a clear surface . But then after you have readied the soil for planting and sowing , along with your expensive veg seeds , millions of weed seeds will pop up , covering them for 6 months doesn't kill them off. You are left with basically three choices , weed killer (roundup etc) if you want poison on your land ? , mulching or manual weeding . The poison route is fine, if ?, you are ok about putting poison on ground, that you intend to grow your food on/in ? Mulching , this works fine as long as you keep up with the mulch . Manual weeding , this is my method ,it is free , always works , doesn't poison , is selective if needed to be and can occupy as much or as little time as you want . This method does depend on how much you are gardening . If you are working an allotment or similar sized plot fine, if you are working 5 acres then hand weeding will take up every minute of the day . You then have to turn to some sort of powered weeding/harrowing , either engine or animal powered. All three methods are on going ,in as much as new weed seeds will blow in and germinate , or be carried in by birds etc , or even bought in with a mulch ?. I am biased towards my method obviously , but everyone will do things their own way . You pays your money and you takes your choice !!!
cheers
Russ