Different types of grass seed are sold at Shannons- I bought the multipurpose by Evergreen which has done well in our very shady garden with poor soil (the garden has a lot of heavy clay sub-soil brought up to the surface when these flats were built). You'll need to break up any impacted top soil with a fork before sowing, and we also used a little compost to improe it. Fortunately (well, for the lawn) it has been a wet summer. You'll need to water at times if it gets dry - water butts and recycling bath/shower water.