A trenching and edging attachment for a riding lawn mower or compact utility tractor preferably includes a base frame, a cutter drive, a pair of pivoting height wheels and a cutter cover. The base frame preferably includes a lengthwise support member, a cutter support member, two support wheel extensions, a drive support extension, a pivot extension member and two attachment yokes. The pivot extension extends outward from the lengthwise support member and includes at least one retention hook. Each pivoting height wheel includes a wheel roller, a wheel yoke, and a height adjustment device. The wheel yoke is pivotally retained in the support wheel extension. The cutter drive preferably includes a cutter driven shaft, a right angle gearbox, a chain drive and a cutter drive shaft. A drive hub is attached to substantially an end of the cutter driven shaft to retain a trenching blade or an edger.