Q: I am going to be installing zoysia sod soon. My lot is heavily shaded but I’m having my trees thinned to help with sunlight. The soil stays a little damp. Would it be good to put down 3″ – 4″ of sand before laying down the sod?
A: You run a big risk of wasting a lot of money. Putting a layer of sand underneath existing soil is not a good idea. Grass roots do not easily grow through soils of different coarseness. Uneven drainage and uneven drying would far outweigh any advantage to having a sand layer. Your contractor can advise on adding materials to help your existing soil drain faster. Anything added needs to be mixed with existing soil down at least eight inches. Zoysia sometimes tolerates a bit of shade but I’ve never seen it do well for long under limb-thinned trees. A tree will produce new limbs and equal shade in just a couple of years after thinning. Zoysia needs at least five or six hours of direct sunshine to thrive and combat weeds.