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We're about to order topsoil and turf. Should topsoil be compacted first, or just leave it loose?

kevinskio
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Steve Dunn
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1 Answers1

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Well the answer depends on exactly what preparation you've already done to the turf bed. If you dug the area over and removed all weeds, especially perennial ones, that should then be raked level and left to settle. If you're then adding topsoil, spread it over, then walk all over it closely, using your heels, to find any soft spots, then relevel with a rake or a long board dragged over the area, so that you know its flat all over. It's not a good idea to use a heavy roller, you don't want to compress the soil deeply, you just need to make sure the soil is even and flat, without dips and hollows. This is necessary not only for good, complete contact in terms of the roots of each turf, but also for having a flat, even lawn over time.

If you can, wait a few days between spreading the topsoil and actually turfing,so ordering the turf to arrive a few days later would be best. The reason for this is that it gives the area a chance to settle and consolidate; any weed seeds or pieces present in the topsoil should produce growth quite quickly at this time of year, and you'll be able to remove those before turfing. Topsoil often contains quite a few largeish stones and pebbles, and they will need removing prior to laying turf - small or tiny bits of stone are okay. When your turf is delivered, you need to lay it pretty quickly, preferably within 24 hours, but certainly within 2 days, so having time to screen and spread the topsoil without the pressure of a pile of turf sitting waiting to go down makes things easier and you'll do a better job of it. If you can't get it down within two days, you need to unroll the turves and keep them watered till you're able to finish.

The top two inches of the turf bed should be friable and relatively loose, to enable the turf roots to penetrate easily, so rake it up just before laying - it should also be damp, not dust dry, and given the weather we have in the UK at the moment, should it continue, that might mean you have to water it before laying the turf.

Bamboo
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  • Rent a ROLLER that you fill with water and roll, rake the depressions, hills and roll again! This is so critical! Sod will grow even on GRAVEL. It comes with its own soil. That lawn bed has to be FIRM or you'll get all kinds of depressions and missing spots where the sod is not connected to the soil. Sometimes it takes 6 or 8 passes to get this right. I got paid big moola to do this correctly and I fired guys who thought that the tractor did enough compacting and emptied the roller behind my back, grins! – stormy Jul 18 '16 at 19:15
  • No, no, no,, Stormy, not recommended at all here in the UK - the climate's so damp this kind of treatment causes significant problems. The only use for a roller of the kind you mention is by sports turf people, and only then very rarely. Look up DG Hessayon's Lawn Expert on this subject.... – Bamboo Jul 18 '16 at 19:36
  • Bamboo, I am so familiar with clay soils and wet climates it just isn't funny. The Pacific Northwest must be very similar to your environment over there...I advise people to never use a rototiller for wet, damp clay soils but a roller is critical to ensure one gets that bed right the first time. This is not at all what we do for plant beds, JUST LAWN. You said to walk upon the soil to find holes...it is the same thing to use a roller only one is more able to find the depressions and hills before laying sod. And a 'grading' rake is essential. I shall look up DG's advice as well! – stormy Jul 19 '16 at 01:56
  • @stormy - except it doesn't work. I've laid more turf in the UK than I care to recall (got sick of it) and using a roller does not find those soft spots, so I went back to what I was taught in the first place - walk over it, on your heels, closely. And that works well, but probably not appropriate for an acre or two... fortunately, most of the gardens I worked in were in town, so probably the largest lawn we did was 60 x 45 feet. But we still heeled it all over... or I did, actually, being the only perfectionist on my team! Better that than being called back by the client for dead low spots – Bamboo Jul 19 '16 at 12:19