Sweet Pittosporum has a dense canopy that shades the ground and drops lots of leaves. A chemical inhibitor in the leaves prevents indigenous plants from growing beneath. It shades out native grasses, and reduces habitat for lizards and birds. Sweet Pittosporum establishes very quickly and starves surrounding plants of nutrients, water and sunlight.

Cut plants off at ground level and immediately paint the stump with an undiluted glyphosate based product. For plants with trunks greater than 50 mm, 'drill and fill'. Drill holes 2-3 cm deep and about 5 cm apart, at the base of the trunk. Fill the hole immediately with an undiluted glyphosate-based product. Best done in the active growth stage in late spring and mid-autumn.