I'm installing a landscape for a client. The current soil is less than satisfactory. The house is built in an area that was built up from digging out a pond and using this soil. It wasn't done right so therefore the good topsoil is under about 6 feet of fill - mainly clay. For me to ensure the plants for at least a year I considered putting compost around them. However if this compost wasn't made correctly I'd stand the chance of burning them up. I was told by a couple of landscape guys to just use a good slow release fert and plant them. As long as we till the soil up really good and the plants get ample water (a irrigation system is in place) they will live. What are your thoughts - how would you handle it? Also, what's a good slow release fert to use - what numbers....? Thanks.