Landscape Gardener using subcontractors - CIS Scheme?

A client of mine is a Landscape Gardener who carries out Estate & gardens management. He uses subcontractors for any HARD landscaping work. Per CIS340 Tree Planting & landscaping in the course of forestry or estate management are not constructions operations" but does this extend to the work my client subcontracts?

Certainly 99% (if not all) of the work is NEVER part of a bigger construction or housebuilding project or contract, its just work carried out for the public who may wish to re-landcape, replace a patio, build new or repair a wall etc.