On the top level you could grow both edible ginger and turmeric. Growing these plants will allow you to enjoy their flavours in your food from your own garden. They would also give you a background level for the whole garden. Some of the cherry tomatoes would also give you a ground cover and plenty of fruit on another tier. Checkout the lovely grevillea ground covers on the net. The bottom tier would be soft with some of the grevilleas available.

They have shallow root system- so near your colourbond fence- the heat in Summer will not only dry the roots, but also burn them and the foliage. They require regular mulching and fertiliser, else the leaves yellow and they start dropping. Given you want them as the 2nd layer in your already narrow hedge, it will be a full-time job keeping them happy I think. If you are not a fan of this level of garden commitment- check out the regular mondo grass (not mini). It grows like a weed just about anywhere! Aganpanthus is another one. Both would be ideal 2nd layers and maintenance free.

Hi, I planted an Australian native hedge infront of my side fence in the back garden ( see photo) three or 4 years ago. Initially the side neighbour's garden had lots of mature trees so I was just going to grow the hedge to the top of the fence.The mature trees have now all disappeared so I would like more screening and a landscaper suggested I plant some ornamental pears to grow through the hedge cutting the hedge back at intervals and planting the pears accordingly. Does this sound like a good idea and does anyone have photos? Thanks

we started with a collections of different pittosporums and some wattles arranged in clumps of three and five in three roughly parallel rows along curved mounds and then added lower growers on both sides with small casuarinas (easily grown from locally collected seed) and some deciduous trees.. our hedge was about 3-4 metres wide alongside a 300m driveway...wattles were great as they grow quickly (but don't last very long) but provide shelter while slower growers establish and it's always good to consider local varieties of trees and shrubs and our cold climate make deciduous trees a bonus for Summer shade and Autumn colour ..but if you need to grow a long hedge focus on starting with establishing the beds with good drainage, big rocks, tree trunks, rubble, old railway sleepers, a watering system and really thick mulch and use a greater number of small tube stock well looked after rather than thinking that bigger plants will fill the space quicker