Family: Apocynaceae (Periwinkle family).
Native of the Mediterranean region.
Occurrence: An environmental weed. Blue Periwinkle is a widespread weed in Australia, and there are some dense infestations in the local area. It particularly favours shady damp places, but can grow in full sun.
It is a widely planted garden species, and most infestations probably come from dumping of garden refuse. Blue Periwinkle forms dense mats that exclude other vegetation. It can form new roots when stems touch the ground.
Photo 1, 2, 3: Blue Periwinkle. Froomes Road. 4: Forest Creek.