A good idea is to go for a walk around the neighbourhood and see what others have done.

The problem is the runners from grass like kikuyu spreading into the garden bed. You could change the grass to something like fescue which is non-invasive. Or perhaps dig really deep into the bed and put some plastic weed control mat at the border of the flower bed and lawn. Then it shouldn’t matter what edging you use.

I used paving bricks so it’s easy to do the edges and still looks nice

We used weed mat along the edges and put down a premade edging we bought from Bunnings and the grass just stopped at the edge of the weed mat.

We used pine logs cut in half but underneath that we had steel pushed into the earth so it didn’t show. We found that worked the best for us.

I found flexible galvanised steel edging was really easy to use. It was easy to install and shape. It’s worked well for our garden

I think Bunnings would be a good starting point.

We have used brick sized pavers to define the border between grass and garden. We elected to put the pavers side by side in a bed of cement to keep them in place. Easy to whipper snip and keep everything neat and tidy. Second hand bricks also look good depending on your house style if it matches in.

You should look for bunnings website.

We have concrete edging which was already here when we purchased the property. We’ve had no trouble with grass overshooting the edging and it’s easy to whipper snipper along the concrete.

We don’t use one!!! There is so much to do and we never get enough time to do it.

How aggressive is the grass? Some is extremely hard to stop. You could use concrete and even shape it if you want to. You could try using weed mat starting at the edge of the grass or even lift the edge of the grass and push a tiny strip of it under the edge of the lawn if it will help. If you can , plant your shrubs a reasonable edge from the grass. Not only will it make it easier to cut the grass but it will give some space to work if the grass does sneak across into your garden bed, also it will be easier to trim your bushes. Hopefully you choose drought tolerant bushes. If you haven’t already chosen your bushes go for a walk or drive around the area and see what others have planted. I suggest you go to a Garden Centre. You may pay more for your bushes but they should tell you the correct time to plant them and whether or not you need to add anything to your soil. If you buy soil ask for assurance that there is no grass seeds in it at all. If there is you may have a disaster to cope with. We learnt from experience