Top Soil and Seed over existing grass

Steve Pearce

Hi all,

To cut a long story short, last year i put top soil and turf over an existing purple gravel garden, as was fed up of the constant battle with leaves/clippings/etc. It looks tonnes better, and in some areas is growing well. In others, though, its doing less well.

The good bits (though could be a bit thicker!);

There are two general problems, i think. 1, in some areas the top soil wasnt very thick above the gravel, i suspect around an inch. Consequently, i think water runs straight through the soil and gravel and the soil therefore dries out and the grass doesnt really grow. WHen i researched at the time the suggestion was that a top soil layer around 2-3"s deep would be good to turf over. A picture of a typical area

Secondly, there are a couple of areas that are almost always in shade (1 in particularly never seeds direct sunlight). The grass never really grew here.

What i therefore hoped to do was buy some more top soil to build up those areas, which i thought i could put over the existing grass and then reseed. That'd give top soil depth (~1" plus turf depth (~1") plus additional top soil, which should give it a better base to grow from. In areas with less sunlight (like above) that are struggling at the moment i could build it up a bit more - im not allergic to a bit of a slope on the lawn (nothing major!), but how deep ought i to go.

Obvious question though is whether that will work and be sufficient? The grass itself isnt weedy, so i dont think that would come through, but do i need to get rid of the grass first. Should i bother mowing/strimming it really really short before i put the top soil on.

One point, we have conifers at the back which are fairly overgrown and block some of the light. I appreciate they will suck a lot of the water out, but assume that a decent layer of top soil should help?

For info, the purple gravel/stones in the bottom image previously covered the whole garden.

Thanks in advance

Steve

Borderline

If you want to build your areas higher, it's not a problem, just mow the grass and then pour topsoil over it. You may have to do this in stages to get it compacted in and make sure there are no air pockets. Once you are satisfied with the area. Make sure the new layer is damp. You can sow the seeds in. For the shadier areas, you can buy seed for shade areas. I have to admit, your layer of soil over the gravel is very thin. You are likely to have a difficult time of having this lawn retain a bit of moisture. I think it will struggle in the summer time when the sun beats down on it. 

Last edited: 07 August 2017 18:31:08