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Scarifying the lawn

My lawn is full of moss.  I have treated it but the spreader wasn't working properly so it is not very even and blackened in places.  I want to scarify and aerate it and may have to give it another treatment so called in one of the companies who do those things and got quotes.  They left me a booklet to read which said that the small domestic scarifiers (electric wire rake),  like the Black and Decker one I own and was thinking of getting my young helper to use,  can cause severe long-term damage and split the stolon of the grass, allowing diseases into the plant. 

Is there any truth in this?  I have no idea what diseased grass looks like but I have certainly got a lot of moss out with mine in the past.



  • StevedaylillyStevedaylilly Posts: 1,078


    I have never heard of that sort of damage to grass based on using an electric wire rake. But, to be honest, I have never considered using that equipment. If you have extensive moss, you will have damaged grass based on the moss suffocating the grass shoots of air and light. My own personal preference is carrying out a manual scarifying with a metal lawn rack after a treatment of weed and feed. Look at the reasons why you have moss as it normally due to excessive moisture and shade to areas of the lawn. If you lawn is in shade and there are overhanging trees or shrubs, then you should prune theses back to reduce the dripping effect to the lawn. This will also improve light to the lawn.

    it would also be beneficial fork over the worst areas, using a hollow tine fork. You can then top dress over these holes with sieved top soil (or John innesc compost)  and Hort.grit. This will improve drainage and allow air and light to the sub soil. This will stimulate new grass growth. Finally, apply a suitable grass seed to the area and water in well and do not allow to dry out 

    Hope this works for you

  • Thanks, Greenfingers. 

    You are quite right, we do have a lot of shade and are surrounded by large oak trees, though they don't exactly overhang the lawn or drip on it.  However, I used to manage to keep it looking very good until my husband became very ill (he died in November) and I lost my help and Green Thumb didn't get round to doing the Autumn treatment.  I didn't get round to scarifying it last year and my son may have cut it a bit too short.  As I said. I have put some of that Evergreen Complete on but hadn't realised that the spring had come off the Scotts spreader so it is very patchy.  Also, the stuff was last year's and though the bag hadn't been opened I think it must have gone off as it still hasn't fully dissolved even after hosing and quite a bit of rain.  I thought I'd give it some more time and hope to get more rain and then go over with my electric rake; much too large an area for me to do it by hand and I am 80.  Then I planned, after it has had a it of a rest, to get it aerated, which will be quite expensive, and get a firm to do the rest of the treatments as required, if necessary treating for moss again in the autumn, which is when these firms seem to do it, though I prefer spring myself as I like to rake out the blackened moss and one has less chance of getting decent weather before it gets too cold to do it.  Interestingly, one firm I had a quote from used a spray treatment which didn't turn the moss black; I wondered how one knew that it had worked.  At least it is pretty weed free.  There were a few dandelions but I have taken them out.

  • StevedaylillyStevedaylilly Posts: 1,078


    Sorry to here of your loss and hope you are coping.

    I normally use a weed and feed without the moss killer as I do not like the burn out that it does to the moss. I am lucky (touch wood) as I have a little moss, but what I do get I remove and then weed and feed 

    I agree that, based on the area of the lawn, then you will need some assistance to get this work done. There are some good lawn maintenance as well as some real bad ones who would not have a clue on what an actual healthy lawn should looks like. So, please read reviews or go on good recommendations on any contractors you decide to employ 

    All the very best for the future and I do hope you get your lawn back to prine health 

  • So when do you remove your moss?  I thought there was a danger of spreading it if you raked it when the spores were active and it had not been treated?

  • StevedaylillyStevedaylilly Posts: 1,078


    I normally rake it out in early spring and autunm prior to feeding the lawn. If the moss is removed when it is still basically alive, then, unless you remove all of the moss, then any remaining will possisbly survive .But when you re-seed the raked area and aerate the new grass will outgrow the moss as long as you keep up this process. There is not many garden in the land that haven't been or are effected by moss build up. The less moss I have, then I can live with it. 

  • Garden noobGarden noob Posts: 260

    I've​ used three methods for scarifying:

    - Electric rake/scarifier like you describe. Personally I think they're fine and wouldn't worry about using them. My only concern is that they're quite violent and when I've used it in the autumn it's taken an incredibly long time for the lawn to look healthy again. I want to try them in Spring in future. They're good if you have a lot of moss, but won't get everything.

    - Hand rake. Too much work IMHO, even for a relatively fit man like me in my 30s! And my lawn is only ~60 sq metres. Good for getting the maximum amount of moss out of lawns, and good for particularly small lawns.

    - Hand rake on wheels that help it glide back and forth. A bit easier than a hand rake, and gentler than an electric scarifier, but still a lot of work.

    You're right that you're supposed to treat moss before scarifying - iron sulphate is the stuff to use. You can buy it separately, or as the active ingredient in moss-killing lawn treatments. Don't add treated moss to your compost or else you may discourage worm activity.

    My lawn is in shade and poorly drained. I'm coming to the conclusion that it's easier to fix the problem each year (i.e. remove the moss) than it is to fix the cause.

  • I've never added the treated moss to my compost heap but was surprised to read somewhere recently  (don't ask me to remember who said it; my memory is going) that it's fine to do so. However, I still won't,

    The trouble with these small scarifiers is that the bags on them are ridiculously small and unusable really so one still has to rake up the moss the machine drags up.  However, that is still a lot easier than raking it out of the grass by hand. It's quite satisfying to see the huge amount it does rake out.  I actually have 5 lawns and the total area is estimated by one firm at 360 sq.m. and 420 sq.m. by another.  To be fair, 3 of them are not rectangles so difficult to measure.  How would you like to handrake that, Greenfingers?

  • Dave HumbyDave Humby Posts: 1,060

    I have an electric lawn rake and find it the perfect tool to remove the moss, thatch and give a preparation for overseeing. Nothing like as 'violent' as a scarifier. With regards to the tiny collection box, this seems to be a common theme with all of them. I try and pick a dry day and leave the box off. I then go over the lawn with the mower to pick up the debris. 

  • StevedaylillyStevedaylilly Posts: 1,078


    i agree, that a very large area of lawn compared to mine. I have a pathway of lawn that leads to a scuplered lawn so hand racking is not much of a problem, even for a 58 year old.

    I would take heed of all the advice on here as it imparts a lot of sound advice if not always the same 

  • The advice is much appreciated.  Thanks to all.  What I have is an electric rake, too.  Not sure what the difference is between that and a scarifier.

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