Nature friendly weedkiller for lawn?!

The safest weedkiller is to hand pull them! However, although I don't want to spend an age on this the following are worth bearing in mind. Firstly the LD50 value for acetic acid is 3310; The LD50 of caffeine in rats is 192. Secondly, yes its a contact which actually means its safer to use it only effects what it touches and works best on young plants. Weeds will still grow back unlike systemic glyphosate which kills the entire plant. Thirdly yes direct application of acetic acid to earthowrms at 5%, 10% and 20% is lethal to earthworms but as you are applying to the foliage this shouldn't be an issue unless they climb up the plant to the leaf. If your concerned about bees dont use any of the following copper sulphate, insecticidal soaps and oils.

 

Unfortunately to get rid of weeds you will need to hit it with a chemical. I know mowing and good fertiliser program may help but if it’s a good coverage of weed then the only way to hit it is by a good herbicide application which as the temps are dropping leaves little choice as the better ones are not on the domestic scene.

the thing to remember is height of cut on lawns is much higher than say on a cricket square or a golf green so weeds tend to survive plus the cutting time ie once a week. It’s why lawns tend to always show weeds more than the low cut areas as you are not cutting the leaf off.

You either leave them or in the spring think about getting someone in and using an early herbicide that works better early season ie, rain fast and designed around low temperature application. I use Praxys for early treatments or where the envelope of treatment is small. I know you don’t want a chemical but that’s why we call it good practice where any type herbicide applied is known to treat the plants targeted at the correct time and when the envelope for treatment is at its highest.