Silver Banksia

Silver banksia (Banksia marginata) is one of the most adaptable natives in the country, and in a garden it settles at about 4m tall and 3m wide. The narrow leaves are dark above and silvery white beneath, so the whole shrub flickers pale in a breeze, and yellow candle flowers open from late summer through autumn. It is slow growing, which is exactly why it stays neat with almost no attention.

Why you'll love it

• Built for hard sites. Frost hardy, drought tolerant, salt tolerant, wind tolerant and comfortable in poor sandy soil.
• Birds through the cooler months. The candles carry nectar when little else is flowering, so honeyeaters work it daily.
• Silver in the foliage. White leaf undersides give it a soft grey cast that sits well with other natives and with coastal planting.
• Low maintenance by nature. Slow growth and no feeding requirement mean it holds its size without regular pruning.

Where it works best

Screening and privacy. Plant 1.5m apart for an informal screen. At that spacing the plants meet without crowding, though this is a slow screen: allow three to four years rather than two.

Coastal gardens and windbreaks. Salt and wind tolerance make it a genuine front garden plant near the sea, and a staggered double row at 1.5m spacing filters wind across an exposed boundary.

Feature planting. Single plants gain character with age, twisting slightly and holding old grey cones long after flowering.

Growing silver banksia in Australia

Position and climate. Full sun, in cool temperate, warm temperate or Mediterranean gardens. It is frost hardy, so cold southern districts are fine. Humid subtropical and tropical gardens are the wrong fit, since sustained wet heat invites root rot.

Soil. Sandy, gravelly and poor soils suit it best. What it will not accept is heavy wet clay, so mound the bed by 200mm to 300mm on clay ground and skip the compost.

Water and feed. Water weekly through the first summer, then leave it to the rain in all but the longest dry spells. Skip standard garden fertiliser: like most banksias it is sensitive to phosphorus, so use a native blend or nothing.

Pruning. Tip prune lightly after flowering to thicken the habit. Never cut back into bare old wood, because it does not reliably reshoot from it.

What to expect when it arrives

It is grown in six sizes. The 140mm packs of ten, 200mm packs of six and 250mm packs of three are the sensible way to buy for a screen or a bank, and small banksias establish faster than large ones. The 300mm, 400mm and 45L plants give you a shrub with structure already in place.

Plants travel upright and are delivered Australia wide, with delivery from $29.95. Expect little visible growth in the first year while the roots go down, then steady progress. Every plant is covered by our 30 day healthy plant guarantee.

Plant care guides and related reading

• The complete banksia care guide
• Browse the full banksia range
• Salt tolerant plants for coastal gardens
• Bird attracting plants for Australian gardens

Common questions

How far apart should I plant it for a screen?

One and a half metres apart in a single row. Closer planting will not speed the screen up and only increases competition for water in the sandy soils this plant prefers.

How big does it get?

About 4m tall and 3m wide is a fair garden average. The species is highly variable, so coastal forms often stay a low shrub while inland forms make a small tree.

Why should I avoid ordinary fertiliser?

Banksias evolved on phosphorus poor soils and standard fertiliser can damage the roots. A low phosphorus native fertiliser once in early spring is plenty, and doing nothing is safer than overdoing it.

Does it handle frost?

Yes. It is frost hardy and native to the cool districts of south eastern Australia. Young plants appreciate shelter through their first winter, after which frost is a non issue.