Answer: Top soil is often sold in bulk and usually is a 3-way mixture (garden soil, compost, sand). Since you already have topsoil, check to see what it contains. If it isn't a 3-way mix you can still use it. Spread 4-5" of organic matter over the top and dig it in to a depth of 8-10". Then level the bed and plant your veggies. Add compost each spring and in a few years you'll have rich garden loam. Raised beds have the advantages of warming up earlier in the season (for earlier planting) and of draining well (no waterlogged roots and no root rot).
Best wishes with your garden!
Q&A Library Searching Tips