My purpose wasn't to dissuade you from having bifolds if it's something you LOVE the idea of but it's a good idea to think through things like what to do about flies and how will it look given there is a step down to the patio so you're going to have a threshold rather than seamless flow anyway. What is your climate? Which way does the back of the house face? It's useful to know the climate to know what will grow well for you and to know the orientation to understand where you get afternoon sun that you might want protection from in summer and where you get winter sun which you might not want to block? There are other questions to work through. Like people have asked, what's your style? Formal or informal? Native? Low-maintenance? Resort? Seasonal interest? Do you want to keep the maximum amount of lawn and plant only sufficient for privacy and shade or is the amount of lawn flexible? Do you like straight lines or curved garden beds? Do you want to extend the patio? Put in some paths between the patio and the back door and the clothes line and down the side? Make a space for a barbecue? Tuck in a garden shed somewhere? Storage for bikes and sports gear? I don't want to say too much until I know what's important to you. But for starters I'd plant a hedge along the back fence, I'd paint the pergola to make it look lighter and airier, I'd put in some paths and garden beds around the back door and clothesline and hws, and I'd plant a tree but I don't know enough about the block to suggest what sort and where to get the best benefit from it. That's what comes to my mind so far.

http://pin.it/c0cD76w A pergola like this along one side, doesn't need to be over the door, would help blend. There are tonnes of native climbers on the Gardening with Angus site.

There are some truly beautiful natives on the scene now. I love acacia cognata for it's lovely mounding habit and the fact it fits into nearly any style of garden. It looks lush and temperate but also flowers. Davidson plum is a native that takes up very little space but drops kilo's of fruit after a few years. If you like tart jam like rosella, and cranberry then davidson plum makes a beautiful tart jam and also a lovely steak sauce. It's very simple to grow and a distinctive looking tree. Also makes an excellent cordial. Dianella is a native strap plant that clumps and looks stunning in the variegated leaf. It's cheap and easy to find and in mass plantings looks the business. and while a coffee tree is not a native few other trees are as easy to grow and beautiful as this one. It grows to below 3 meters in a lovely dense bush shape. The leaves are deep green and glossy and it flowers with hundreds of delicate white blooms that smell like jasmine. It does not need pruning and looks good for absolutely years. If you want a lush look to your garden you can't go past a $7 K12 coffee tree that will fill a gap and look amazing. We put ours in as seedlings about 7 years ago and they are mature now. Both are beautiful shaped trees that have never been pruned and need zero maintenance or watering. They are fabulous ornamental trees that produce about 5kgs per tree of coffee beans a year. A truly worthy screening plant when you want a lush backdrop and maximum privacy. And for a waterfall effect over terraces like no other you can't go past dichondra silver falls. It's native.

Hi Laura, I also love your inspiration photo. I think you're on the right track for what you want. It looks like an early summer image due to the jacaranda flowering so I would try and get a bit more colour in the planting and spread your flowering season to be as long as you can by choosing winter, spring and summer flowering plants. It appears that you have the ability to build one side of the garden up as you have a foudation below the fence. You shouldn't build it up in front of the actual fence as it will eventually rust out. If you do build it up in part, you could build seating into this to make two uses out of the retaining. You could intersperse this with the cortens to reduce the cost as that wont work so well for seating. Recycled timber could do the job and maybe mix with some gabions, which you can do on the cheap yourself if you have a source of rubble or stones. C.