Roller Coaster Banksia (Banksia integrifolia 'Roller Coaster') is the prostrate form of coast banksia, and it behaves nothing like the tree. It holds at about 40cm high and runs to 4m across, throwing long horizontal branches over the ground and spilling over the top of a wall. Yellow flower spikes through the cooler months bring honeyeaters down to eye level.
Why you'll love it
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A banksia you can use as groundcover. Roughly 40cm tall by 4m wide, spreading flat instead of building into a tree.
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Bird food at ground level. The yellow candles carry heavy nectar, and they sit low enough to watch honeyeaters work them.
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It takes the hard positions. Drought, salt, wind and poor sandy soil, so exposed coastal blocks and dry batters suit it.
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Fast cover, no shaping. Fast growing for a banksia, and it keeps its flat habit without pruning.
Where it works best
Groundcover and mass planting. Plant 2m apart. Branches interlock within about two seasons at that spacing, and planting tighter only costs you plants without closing the gaps sooner.
Retaining walls and slopes. Set it along the top of a wall and let the branches cascade over the face. On a batter the roots hold loose ground through summer storms.
Coastal gardens and rockeries. Salt spray and sand are its native conditions, and among rocks it reads as a deliberate planting, not a lawn substitute.
Growing Roller Coaster Banksia in Australia
Position and climate. Full sun all day, or the growth goes thin. It suits subtropical, warm temperate and cool temperate gardens and takes light frost once established, so hard frosting inland districts and the tablelands are a stretch.
Soil. Free draining and lean: sand, gravel, decomposed granite, poor ground of any kind. Wet clay it will not survive, so build a raised mound if that is what you have.
Water and feed. Deep soak weekly through the first summer, then let it live on rain. Banksias are sensitive to phosphorus, so use a low phosphorus native fertiliser once in early spring, or skip feeding. A standard complete fertiliser can kill it.
Pruning. Tip prune the running leaders for the first two years to push out side branches, then leave it alone. It does not reshoot reliably from bare old wood, so never cut beyond green growth.
What to expect when it arrives
We grow it in eleven sizes: tube, 140mm in packs of ten, 200mm in packs of six, 250mm in packs of three, 300mm, 400mm, and 25L, 45L, 75L, 100L and 200L. For groundcover and slope work the tube and 140mm packs are the sensible buy, since a young plant establishes faster and reaches the same spread.
Banksia roots dislike disturbance, so plant without teasing out the root ball. Expect a quiet first month, then real spread from the second season. Plants are delivered Australia wide, with delivery from $29.95. Advanced and large stock is freighted at cost, and every plant carries our 30 day healthy plant guarantee.
Plant care guides and related reading
Common questions
How far apart should I plant it?
Two metres apart for a dense groundcover. Each plant reaches about 4m across given time, so 2m spacing gives overlap and full cover without wasting stock.
Will it stay flat, or does it grow upright?
It stays prostrate, holding around 40cm. Occasionally a plant throws a vertical shoot reverting towards the tree form: cut it out at the base as soon as you see it.
What fertiliser is safe to use?
Only a native blend low in phosphorus, once in early spring. Standard fertilisers and animal manures carry enough phosphorus to kill banksia roots.
Can it handle frost?
Light frost, yes, once it has a season in the ground. Repeated heavy frosts in cold inland and tableland gardens will burn the foliage.