What is the best way to de-weed a lawn?

Question

As a very inexperienced gardener, what is the best way to de-weed a lawn?

Having recently moved into a new house, the garden is generally in a very good condition- the previous owners were obviously keen gardeners, and have taken very good care of it. However, there are a few weeds starting to grow on the lawn- I guess when you know you're going to be moving out, there's less incentive to keep at it...

The garden in my previous house had obviously been neglected for years before I moved in, so although I did quite a lot of work on it during the time I was there, that was mainly getting rid of the brambles, nettles and other weeds that had been growing wild for years- there was no lawn, just a soil bed, a couple of bushes/ shrubs, and whatever else had taken root. So I generally just dug out all of the weeds and strimmed the overgrowth to try and get on top of it.

But given that the garden in my new place is in very good condition, how can I best 'stay on top of it', to keep it in this good condition, and not let it get overrun with weeds, etc?

I did spray the weeds I saw that were starting to grow up through the lawn with some 'Roundup path weedkiller' a couple of days ago- which was just what I'd bought to try and get on top of the garden in my previous house. In retrospect- perhaps this was the wrong thing to use on a lawn... although it has killed the weeds, it has also left dead patches of grass in the areas around where the weeds were growing.

So how can I best re-establish the lawn in the now dead patches where I have killed the weeds? Should I dig up the dead weeds, sprinkle new grass seed on those patches, or something else?

I did pop to a garden shop near me and pick up some Growmore, which is apparently general purpose fertiliser for all around the garden- should I just sprinkle that on these patches?

Answer 1

I take it you did not read the label on the Roundup Path Weedkiller, which states quite clearly 'do not use on lawns'...so that's the first lesson, read labels and instructions! Unfortunately, now that you have used it, you will need to wait at least 4 weeks to make repairs to the lawn where the bare patches are. And a word about glyphosate (particularly Round up products) - never use this unless it is absolutely unavoidable, and even then, use as little as possible. Roundup can persist in soil for a lot longer than the advertising says; it also destroys various micro organisms that contribute to healthy soil, so if you use it, only apply it to strongly growing foliage, and don't get it on the soil. Path, patio and driveway treatments should only ever be used on those areas and nowhere else,with care being taken to avoid spray drift or run off if applied by can.

Growmore is a very useful general purpose fertilizer - it can be spread onto beds and borders in spring as growth begins and lightly turned into the soil, but do not use it now, it's too late in the year because the growing season is coming to a close. Don't apply it to your lawn now either. Lawn treatments at this time of year should be specially formulated for lawns and will say Autumn on them - these are granular products which break down very slowly over six months,whereas the spring and summer formulations break down more quickly, over six weeks, because the grass is growing strongly. However, I would not particularly recommend the combined lawn products (mosskiller,feed and weed ones); it is much better to use a lawn weedkiller such as Weedol Lawn Weedkiller, which is mixed in a can and watered onto the lawn, because it is more likely to kill lawn weeds, with a separate lawn feed without weedkiller. But that's for next year now...

After four weeks, rake up the bare patches in the lawn so you have a friable (loose and fine) layer of soil on top, tamp it down with the back of a rake and apply grass seed. It may not do much this year because it will be October, which is a bit late,but worth a try since you live in a warmer region of the UK - you may need to repeat it in spring if it doesn't grow. Never sow seed if you have used a fertilizer or weedkiller in the previous 4-6 weeks (depending on the product) or are intending to use one in the next 6 weeks, because the seed won't grow.

There are other options for removing lawn weeds,but it depends on what the weed is - dandelions can be dug out with a long, sharp knife to remove its long taproot, but other, spreading weeds such as speedwell are best dealt with by a lawn weedkiller.

I am not sure whether you are only asking about how to maintain a lawn,or whether you want to know how to keep the rest of the garden in good condition, but in respect of lawns, try to get hold of a copy of D. G Hessayon's The Lawn Expert - it's out of print now, but last time I looked,there were second hand copies available on Amazon, very cheap. Although certain pesticide treatments mentioned within are likely long since out of date or withdrawn, the book is invaluable in terms of practical advice on how to maintain a lawn, irrespective of chemical use.