Top Dressing of Lawns is beneficial. It encourages new basal growth of the grass plants - giving a thicker sward of grass. Top Dressing is also a good way to 'level out' the bumps and hollows in an uneven lawn.
Top dressing is normally carried out in mid spring. It can be done at any time in the growing season (March-October), but a dressing in the spring soon 'disappears' under the resultant lush lawn growth. Earlier in the growing season - but not in the autumn - a suitable fertiliser or feed can be added to the top dressing to give that little bit extra.
If well mixed in with the top dressing, it is a good way of applying a 'tonic' mix to the lawn. However, if the top dressing is spread over an area that has recently been hollow tine aerated, then mixing fertliser with the top dressing can result in localised 'hot spots, as the compost sinks down into the hollow cores.
Yes it can make the lawn look a little untidy right after carrying it out - even un-usable for a week or maybe two. But the benefits of top-dressing your lawn will be seen to advantage for the rest of the year.
If you study all the fine sports lawns - tennis, and bowls for instance - you will find that top dressing of the turf is an essential maintenance operation.
The type of top dressing mix to be used varies according to your basic soil type. Normally, I use equal parts of sifted top-soil, sharp sand and peat. (If the lawn is in need of a feed, or for extra 'oomph' I use multi-purpose compost instead of peat! (It it often cheaper as well!) For Lawns on heavier soil, I would leave out the soil in the mix, and use 50/50 sharp sand and peat/M.P. compost.
Mix the ingredients well - on a dry day - ensuring that there are no lumps in the mix.
For me, a large builders' wheel barrow has always been the best place to do this top dressing mix. It holds enough to do a half hour of spreading and raking, and can easily be transported about the lawn. Obviously, top dressing for larger lawn areas are best mixed on the ground - an 8x4ft shuttering ply being ideal if there is no large flat concrete area that can be used.
Lightly spread to mix over the lawn. It is better to do it lightly and in several applications throughout the season, rather than 'smother' the lawn grass in one go!
I normally use the back of my wide 'Landscaper's' rake to spread the mix and 'brush' it into the grasses of the lawn. A good stiff broom will also do the trick. Make sure that the mix goes down into the sward. On large uneven areas - and providing your back will put up with it, you can use a straight edge piece of timber for the spreading.
I have even see a 3x2ft sheet of ply being used - standing it upright and dragging the top dressing about the lawn! Easier on the back than a straight edge!
The landscape rake - or the back of a wooden pegged hay rake are ideal. they both have a wide head - normally 24 - 30in (60-90cms) wide so are less likely to follow the contours of the lawn surface if uneven. Small garden rakes tend to move up and down - following the contours of the ground - ok if you are happy with an undulating lawn - and why not!
The grass should be showing through - as in this picture - after the top dressing has been applied and well raked/brushed in. A few days of good growth, and the lawn will be back to its normal green - hopefully showing signs of a better colour within a few weeks.
For those little hollows, apply a little extra mix. Again not too much. Far better to do these in several applications throughout the season. All manner of small hollows can be treated within the time frame of a couple of months to level the lawn out - and what a difference it will make overall. The mowing will be easier and more effective, and there will be fewer scalping marks as with an uneven lawn. Totally a win/win operation.
'Rough up' the area with your fingers to get that grass showing through.
You won't even need to use the rake for this - it just happened to be lying there when the photo was taken! (And with the teeth pointing upwards - stupid man!)
Top dressing can and should be used on established lawns, but there is also a good case for usinhg top dressing on neglected lawns. Do the first few cuts or so, and once the new grass starts to show through, treat it to a few dressings as above. Many a patch of rough grouns has been turned into a lawn - using this and other normal lawn care operations.
This - as they say - is one I did earlier! Top dressing really does make a difference to your lawn, and has long lasting effects. If you have a lawn that is a little unsettled - such as a lawn laid during the last 3 or 4 years - then tip dressing is the best way to even out all the ups and downs.
If you have an established lawn that is uneven, then try top dressing as a first remedy - and certainly before any ideas of ripping it up and starting again!