Banksia
Banksia spp.
Sun, grit, and lean ground — feed it phosphorus or set it in soil that holds wet and it will not last the year.
- Type
- Shrub · Perennial
- Botanical family
- Mixed / other
- Foliage color
- Green · Silver and gray
- Flower color
- Orange
- Sunlight
- Full sun, with six hours of direct light a day as the minimum.
- Watering
- Weekly until it takes hold, then very little — it is drought-tolerant.
- Feeding
- A low-phosphorus native feed, in spring only.
- Frost tolerant
- Yes
- Flowering
- March
- Pruning
- Tip-prune lightly after flowering, and never cut it hard.
- Mar–Mar Bud Break
- Mar–Jun Flowering
- Jun–Dec Fruiting
- Dec–Dec Dormancy
- Jan–Mar Dormancy
- Plant spacing
- 6 ft 7 in
- In-row spacing
- 6 ft 7 in
- Between rows
- 8 ft 2 in
- Square-foot density
- Not suited to SFG
- Root system
- Woody and fibrous
- Working depth
- 12–24 in
- Can reach
- 3 ft down where the soil allows
- Spread
- 10–13 ft across, about 1.5–2× the width of the plant
- Shallowest pot
- 20 in of soil
A shallow woody framework with the fine feeding roots in the leaf litter above it. Those feeders are mostly under the outer half of the canopy rather than against the stem, which is where water and feed should go.
It makes proteoid roots, dense brushes of fine rootlets in the surface litter that scavenge phosphorus from soils that have almost none. A normal fertilizer is therefore poisonous to it: use a low-phosphorus native feed, or none.
The habit is Banksia’s own; the figures are what that habit usually comes to at this size, not a measurement of this species. Roots follow the soil either way: a compacted pan, a high water table or heavy clay stops them well short of any of it, and deep open ground lets them go further.
- Scale insects Scale insects on the stems
- Phytophthora root and foot rot Phytophthora root rot, above all where the soil drains badly
- Frost damage Frost damage while the plants are young
- Banksia borer (Agrianome spinicollis) in the stems
Beneficial predators that hunt this plant's pests — grow their favourite flowers nearby to recruit them. companion plant
- Hoverfly SyrphidaeHunts Scale insects
Bee-mimicking flies whose legless larvae graze aphid colonies clean while the adults pollinate. A ribbon of shallow, nectar-rich flowers kept in bloom all season recruits wave after wave of them.
- Ladybird (lady beetle) CoccinellidaeHunts Scale insects
The gardener’s favorite ally: adults and their alligator-shaped larvae each eat thousands of aphids, plus scale, mealybugs, and other soft-bodied sap-suckers. Grow flat, open flowers for the adults and never spray a colony that ladybird larvae are already working.
Grevillea, Hakea, Callistemon (Bottlebrush), Lomandra, Kangaroo Paw (Anigozanthos)
Shrubs, like this one.
The Cottage Garden Companion — the gardener's herbarium at cottagegardencompanion.com