April at Tibbetts Brook Park sounds like water and geese and, somewhere up the hill, the first mower of the year. PG General Landscaping LLC starts its season right about there — the spring cleanup, beds raked open, winter's sand swept off the walks, the lawn given its first real cut. Then comes the long green middle of the year: weekly mowing, edging, trimming, mulch turned into the beds, hedges kept in line. In fall the maples let go inside of a week and the leaves go out just as fast. The work is plain and the result is not — a lawn in Yonkers that looks intentional from the curb.