There are so many different fertilizers with different numbers that it is about impossible to recommend one. Just remember that the first number is nitrogen which grows foliage (blades of grass). The second number is phosphorus which grows buds and blooms which you don't really want. The third number is potassium which enables overall plant growth. So, IMO, you want a fertilizer with a higher first number, a low middle number and a third number higher than the second number but lower than the first number. A plant needs all three but grass needs more nitrogen to flourish than say a tomato. Too much nitrogen in a tomato means a plant with more foliage than it needs and fewer tomatoes. With grass you want more blades than seed heads so more nitrogen is needed.