Yvonne Hargreaves, Euroa, Victoria
I inherited a grevillea when I bought a unit last September. It was badly out of shape, as it was up against two very old bottlebrushes, which we removed. We cut off all the dead limbs on one side, and quite a lot of new growth has appeared (right). What is the best way to prune it so I don’t lose the wonderful flowers, which the birds just love? It has flowered beautifully since September. Angus Stewart says You have done precisely the right thing by pruning in spring, as there is a risk that if you prune now, you will encourage soft new growth that is likely to be damaged by frost. Wait until next spring, when you can prune as hard as is necessary to create a more even shape. Look for several healthy new shoots or branches that will grow out to create an evenly shaped bush, then use a nice sharp pruning saw to cut just above these at an angle, so that water cannot collect on the subsequent wound. Be aware that a really hard prune back to a bare stump tends to create a lot of vegetative growth, and so it may be a year or two before that part of the plant starts to flower again.
At the same time as pruning, feed it with a handful of low-phosphorus native plant fertiliser, and water it in well. As the grevillea grows back, you can also tip-prune the new shoots to encourage extra bushiness and even more flowers. Over time, those extra shoots that form will flower at their ends and produce the most spectacular display possible.