Hi sunnyjohn
with regards to your weeds reappearing problem, if you have a patch of land you can leave idle for a month or two you could try sterilising the soil with a 10% solution of formaldehyde. Mix it in a watering can with a rose attachement and pour it onto the affected soil at a rate of 1 gallon to a square yard or so. Soak the top soil then cover with plastic for 10 days. after ten days lift the plastic and dig over the soil and replace the plastic for a further 10 days then lift the plastic and turn the soil over again. you should then have sterile soil ready to start again. - warning this kills everything, both beneficial and pest including worms. I dont use this method except as a complete clearance and a last resort
