Agapanthus- you great us in summer with your friendly ball shaped flowers, you don't need much attention or care you just grow and grow. Come mid summer your flowers start to fade and your once attractive features are replaced with dull looking seed heads. Then you persevere throughout autumn and into winter with your long strappy leaves unscathed by drought or light frosts only to shoot up yet another blue pom pom come next summer.
If you enjoy the sight of agapanthus in flower lining the driveway or the low maintenance function that they provide then that's fair enough (I know I do!). However there are things to consider when it comes to this plants ability to readily spread. Each agapanthus plant is able to produce 2,400 seeds on average- these are then spread by water, wind or dumped garden waste. Aside from seed production, the primary method of spread in Victoria is vegetative means i.e. they multiply by themselves in clumps. A plant with such qualities, (in many cases and for obvious reasons) has the tendency to wonder beyond the drive way.
To avoid the problem of unwanted spread there are a couple of things that can be done. Firstly- to avoid the problem of seeds spreading, (whilst still be able to enjoying the plant in full bloom) cut off the seed heads once the plant has finished flowering (roughly now!). Secondly-plants in unwanted areas can be dug out, keeping in mind that all the underground roots (rhizomes) must be removed and disposed of appropriately. Any rhizomes left in the ground will regrow- even plants left lying upside down on the surface may take root and regrow, therefore correct disposal is important. The root system is fairly shallow meaning that plants can be peeled over and up-ended with less effort than one might expect.
