I think the humble Aggie and the Hydrangea elicit the widest range of responses - both good and bad! A classic Grandmum's plant, the Agapanthus has enjoyed a recent resurgence due to its remarkable adaptibility to a wide range of conditions, its price and its spectacular flower.
(Gorgeous photo by Werner Lehmann)
It works particularly well as a mass planting along a driveway or garden edge, also as large drifts under trees or out in the open. Aggie's are amazingly tolerant of a wide range of soils, from sand to heavy clays. They are also drought, chlorine and salt tolerant. While it doesn't spread rapidly, some Councils and Bush Regenerators do regard it as a weed.
There's always a couple of white ones mixed in there at the nursery! Best to buy them when in flower. Having said that, it does look good if you're after an infomal border.
Aggies might elicit loathing in some quarters but here they have given inspiration to British printmaker Angie Lewin in this beautiful screenprint.
They certainly have their use and place, perhaps keep an eye on them if you live near the bush, otherwise enjoy this wonderful plant!