Yeah, to some extent, annie: they love a good prune once a year after flowering, mine have always responded positively, plus they also like to have the dead flowers removed, though that can be a tedious task. I tend to prune to shape, that is I cut away all the dead flower 'sticks', then shape the bush to give it a balanced appearence. B.

It could be several things. Grevilleas as a group tend to like dryness and good drainage. It may have decided that your soil is too heavy for it. They can succeed in clay soil, but if you have a heavy cracking clay you would do better to choose another plant. (Though Grevilleas can be grown on such soil in raised beds of something lighter) The roots near the surface are crucial. They hate disturbance, so digging around the roots can make them miserable. They love a mulch of something well-aerated like coarse woodchips, which they can get their roots up into. (A shallow layer of compost and leafmould under this is good). Sometimes adding mulch can save a plant which is hating its damp, heavy soil, by giving its roots somewhere to go. They hate root competition, especially from grass, which should be kept well outside the dripline. They are prone to phosphorus poisoning, so you can kill them by using a normal "balanced" fertiliser. Here we use a special low-phosphorus fertiliser for them, or refrain from fertilising at all. They really don't need it, as their roots are super-efficient at using what little nutrient there is, in a poor soil. (which is why they OD if given a too-rich environment). Best of luck Trish

Grevillea olivacea does well west of Toowoomba, where the soil pH is 7 or more, which has made me wonder whether it's a bit of an exception to the "prefer acid soils" rule. Does anyone else know this? I'd like to know what the pH was, before recommending adding sulphur and acidifying mulch. A healthy G. robusta would seem to be an indicator that it's acid enough. It may be hating the daily watering regime, too. And if you've fertilised, the Grevilleas may be a lost cause, as it's hard to remove phosphorus once it's been added. (G. robusta is phosphorus tolerant, however.) But as lillypilly says, the most likely cause is the clay soil. Raised beds with imported sandy soil might give you more success. But is it worth it? Growing plants to suit the soil can be altogether more rewarding than trying to modify the soil to suit the plants. Best of luck Trish.

I have replied to your identical post in the Gardening in Oz Forum.