How to grow banksia trees

Banksia are a wonderfully versatile native Australian plant to grow in your garden at home. They can come in the form of a groundcover, a shrub or even flourishing trees. Banksia are easily recognisable by their serrated leaves and flower spikes, which come in greenish-white, yellow, and orange-red. Banksias belong to Protea family and there are more than 200 species of Banksias. There are over 198 banksia species in Western Australia alone, with another dozen or so varieties found in other states and territories of Australia.

If you have ever wondered how to grow banksia trees in Perth then look no further. Banksia are a relatively easy tree to grow, and there are a few tricks to successfully growing banksia trees in Perth, Western Australia. Get these right and you will be laughing.

When to plant banksia trees in Perth:

The best time of year to plant banksia trees is in Autumn. Allowing them to establish for a few months will help them make it through the hot summer.

How much water do banksia trees need:

The the first year or two it’s best to water your banksia tree twice a week until it has established itself. Your banksia plants will flower regularly and will continue to develop as it grows. After two years it should be well established and a lot hardier.

Types of banksia trees in Western Australia:

There are more than 200 species of Banksias. There are over 198 banksia species in Western Australia alone, with another dozen or so varieties found in other states and territories of Australia. A few of my favourite banksia varieties are listed below.

• Banksia pilostylis – Banksia philostylis is medium sized bushy shrub with dense foliage made up of long saw-toothed silvery-grey leaves. From mid spring to early autumn it bears cylindrical spikes of scented, cream or greenish yellow colour flowers. The flowers of this banksia make good cut flowers
• Banksia prostrate – Banksia paludosa Prostrate Form is a small compact shrub growing to about 0.5m tall and up to 1.2m wide. Although it is suitable for small gardens and has dense attractive foliage, it tends to be overlooked for varieties that have brighter cones. From autumn to early winter it produces cone shaped spikes of dull yellow flowers. The mid-green leaves have a white underside. They are obovate to lanceolate in shape, the margin is mainly smooth with occasional serrations.
• Banksia longifolia – This beautiful banksia was known as Dyandra longifolia until 2007, when it changed it name to it’s current name Banksia prolata, which is from the Latin prolatus “elongate”, in reference to the long, narrow leaves. Banksia prolata is a very attractive Proteaceae species endemic to the Esperance district of Western Australia.
• Banksia tricuspis – Banksia tricuspis os a spreading medium shrub or small tree with pine-like leaves and large yellow flower heads. Suitable to most well-drained light soils with dappled shade to full sun positions. Should be frost and drought tolerant.
• Banksia victoriae – Medium to tall shrubby plant up to 6m high with very often narrow in spread. It has very woolly foliage with soft, greenish to grey-white new leaf tips. Flowers orange and woolly-white acorn-shaped in Summer and Autumn. Best suited to a warm, open and well-drained site with slightly acid to slightly alkaline soil. It flowers at an early age.
• Banksia sphaerocarpa – Ornamental small to medium shrub with fine foliage and yellow flowers. Plants are variable in height according to seed grown. Plants can range from 12 cm to 15 cm or one variety B. sphaerocarpa var. dolichostyla can reach 9′. Frost and drought tolerant. Suitable to most soils and situations, including coastal exposure. Useful screen or low windbreak. Great pot plant banksia variety.
• Banksia sceptrum – Ornamental medium shrub 6-12′ with bright yellow terminal flowers in summer. Prefers well-drained light to medium soils in full sun position. Frost and drought tolerant once established. Suitable coastal or inland and can be grown as a hedge or windbreak. Tolerates alkaline soils. Excellent cut flower.
• Banksia solandri – Ornamental foliage shrub or small tree with creamy brown flowers. Frost and drought tolerant. Suitable to most soils and situations, including coastal exposure. Shrub forms makes a great container plant and screen or windbreak.
• Banksia praemorsa – Dense, upright, ornamental banksia very adaptable to a wide range of well-drained soils (sandy or heavy clays) and positions. It is tolerant of moderate frost, extended dry periods, strong winds and coastal exposure. Large yellow or wine red flower heads which are sometimes terminal or within the shrub. The yellow form flowers over a longer period.
• Banksia speciosa – A spreading medium shrub to small ornamental tree variety 20-45 cm. Creamy-yellow long lasting flowers, with thin, silvery grey-green deeply toothed leaves. Flowers most of the year. Well-drained, light to heavy soils in open sunny position. Tolerant of alkaline soils. Drought and moderately frost tolerant. Grown commercially for cut flowers.
• Banksia honeypot – A low growing shrub to 60cm, with honey-coloured flowers in autumn to early spring. ‘Honeypots’ is laden with nectar-rich flowers from late summer through to spring.

How to grow banksia trees at home:

Growing banksia at home in the garden is pretty straightforward.

1. Choose a sunny spot with well drained soil. Enrich the soil with a Dynamic Lifter Soil Improver and Plant Fertiliser. If the soil is heavy clay based or poorly drained, add gypsum and fork in well to improve drainage and consider planting into a raised mound of well drained soil.
2. Dig the planting hole twice as wide and to the same depth as the root-ball. Remove the shrub from the container, gently tease the roots.
3. Position in hole and backfill with soil, gently firming down. Form a raised ring of soil around the plant, creating a well so that water will go where it’s needed most. Water in well.
4. Mulch around the base with organic mulch such woodchips keeping it away from the trunk.
5. Water regularly, twice a week, until established and then water as required.
6. Feed banksias each spring and autumn with a plant fertiliser suitable for feeding Australian native plants. You want one which will provide slow release organic nutrients to promote healthy leaf growth, strong root development and lots of flowers.

How to grow banksia trees in pots:

You don’t need a large space to have your very own banksia. Growing banksia in pots is easy, fun and rewarding! In general growing banksia in pots is a great idea. Below are the steps on how to how to grow banksia in a pot;

1. Choose a dwarf banksia or a compact banksia like ‘Honey Pot’ or ‘Birthday Candles’. Place the pot in a position that receives full sun.
2. Fill the pot with a quality potting mix.
3. Carefully remove the plant from the pot disturbing the roots as little as possible.
4. Position in hole and backfill with potting mix, gently firming down. Water in well.
5. Mulch with woodchips and water in well then water as required.
6. Feed banksias each spring and autumn with a plant fertiliser suitable for feeding Australian native plants. You want one which will provide slow release organic nutrients to promote healthy leaf growth, strong root development and lots of flowers.

How to fertilise banksia trees:

Fertilise your banksia trees every spring and autumn with a Dynamic Lifter Soil Improver and Plant Fertiliser.

When do banksia trees bloom:

Banksia grown from seed take two to three years before flowering. Once mature the flowering period is typically from late summer, right through autumn, winter and even into spring.

When to prune banksia trees:

The best time to prune Banksias is after flowering. While it won’t actually hurt the plant to leave the old spent banksia heads on the plant, you can prune these back as desired.

How long can banksia trees live:

It is commonly believed that banksia trees can survive for over 100 years.

Companion plants for banksia trees:

Banksia’s can be used as hedging plants, when used in this way planting some complimentary plants like Carpobrotus Claucenscens also known as ‘pigface’ which produce a striking bright pink flower is a nice combination. Adenanthos Sericeus commonly known as ‘woolly bush’, is native to the south coast of Western Australia compliments nicely wit its soft, silver-grey foliage and red flowers.

Banksia trees care and common problems:

Banksia are a fairly low maintenance plant, however depending on the type of banksia that you’ve planted, and your growing environment, and conditions. Here are some of the most common issues.

• Root rot – Root rot is one of the major killers of banksia. Because it is a drought-tolerant, warm weather plant, it can easily become damaged if it’s exposed to too much water. You will see the plant wilting and the leaves may turn brown.
• Phosphorous toxicity – The reason you don’t want to fertilise banksia too often is because it can kill it! High levels of phosphorous will end in yellow, damaged leaves, and eventually the plant itself may die. To keep your banksia healthy, only use low phosphorous fertiliser, and do not fertilise too frequently.
• Caterpillars – Caterpillars tend to be most drawn to banksia. Caterpillars can be dissuaded by something like eco-neem safely.

On a whole, though, once banksia have properly established themselves, it’s difficult to deter banksia from growing happily.

Check out our other how to grow in Perth guides:

• How to grow Australian hedging plants
• How to grow Cottonwood hibiscus trees
• How to grow crepe myrtle trees