How To Grow A Jacaranda Tree | Easy Step-By-Step Guide
Loved for its vibrant purple flowers and lush summer foliage, the jacaranda tree is a common sight across most of Australia’s capital cities. From Perth to Sydney, you can find these elegant trees blooming from late October through to early December, leaving brilliant puddles of violet petals in the streets.
Contrary to popular belief, the jacaranda tree is not native to Australia. However, it does grow well in many areas of Australia—including Brisbane—making it a popular choice for homeowners looking to add a statement tree to their gardens. In this comprehensive guide to jacaranda trees and how to grow them, we’ll cover the jacaranda’s origins in Australia, as well as its ideal growing conditions and everything else you need to know to successfully grow one in your own garden.
Jacaranda tree overview
Jacaranda trees are one of the most recognisable trees in Australia, thanks to their distinctive spring flowers. Here is a quick overview of the key characteristics of the jacaranda tree that we discuss in more detail throughout this guide.
Scientific name: Jacaranda mimosifolia
Plant type: deciduous tree
Size: average height of 8 – 15 metres; average branch span of 4.5 – 9 metres. These proportions result in the jacaranda having a distinctive ‘umbrella’ shaped appearance.
Foliage: bright, shiny green compound leaves with a fern-like appearance. The leaves turn bright yellow in autumn before falling off in winter.
Flowers: mauve to deep purple in colour, flowers appear between late October and early December, generally on bare wood before the leaves appear.
Climate: tropical, subtropical or mild climate, provided there is no risk of frost.
Lifespan: jacarandas reach maturity after 20 years, and have an average lifespan of 50 years, although some specimens have been known to live for over 100 years.
Jacaranda tree description and characteristics
Growing between 8 and 15 metres tall, and 4.5 to 8 metres in width, the jacaranda tree is a large deciduous tree with striking purple spring flowers. The trunk is relatively short, and it is not uncommon for the branches to span a greater distance than the tree’s height, giving the tree an ‘umbrella’ shaped appearance.
Jacarandas have bright green foliage with a fern-like appearance, due to the many small leaves that make up each compound leaf. Each compound leaf is about 30 – 40 centimetres in length, and consists of hundreds of smaller oval shaped, pointed leaflets, about 10mm long by 4mm wide. New foliage is bright green however the leaves change to a bright yellow in autumn before the trees shed their leaves for winter. Jacaranda tree bark is thin and light greyish brown in colour. As the tree matures the bark changes from being smooth to having a rougher texture.
Come spring and early summer, bright purple flowers appear on the tree’s bare branches before leaves regrow. The tubular flowers are approximately 3 – 5 centimetres in length and vary in colour from pale blue through to deeper shades of purple. They typically cover the entire tree before wilting and falling to the ground.
Jacaranda tree origins
The species of jacaranda tree most commonly found in Australia is the sub-tropical Jacaranda mimosifolia, which is typically referred to simply as ‘jacaranda’ or in some instances ‘blue jacaranda’. Although widely planted across Australian cities, Jacaranda mimosifolia is not native to Australia. Rather, the jacaranda tree is native to South America where it naturally occurs in north-western Argentina and southern Bolivia. Despite being commonly found across the world from South Africa through to southern Europe, Jacaranda mimosifolia is now considered vulnerable in its native range owing in large part to forest logging.
So how did the jacaranda tree come to be such a mainstay of Australian streetscapes? Historical records suggest that the jacaranda tree first arrived in Brisbane, from Argentina, in the mid 1860s, when Walter Hill, a former director of the Brisbane City Botanical Garden, bought some jacaranda seeds from a ship’s captain. The first of these trees to be planted in the botanical gardens is immortalised in Godfrey Rivers’ famous 1903 painting ‘Under the Jacaranda.’
Much folklore surrounds the jacaranda’s rising popularity between the late 1800s and mid 1900s. While the civic beautification programs of the early 20th century led to the jacaranda tree being widely planted across Australia’s capital cities, some people believe that many of Sydney’s oldest jacarandas share a common connection. According to urban legend, a nurse at one of Sydney’s hospitals gave a jacaranda seedling to each new mother so that they could watch the tree grow alongside their child.
Nowadays, some of Brisbane’s oldest jacaranda trees can be found in New Farm Park and the City Botanical Gardens. They’re also found throughout the University of Queensland, where their flowering is commonly associated with final exams. As the old saying goes ‘you better start studying for your exams before the jacarandas flower.’
How to grow your own jacaranda tree
Although they aren’t commonly planted in urban streetscapes anymore, jacaranda trees make a wonderful statement addition to the home garden. Being a deciduous tree, they not only provide beautiful spring and autumn displays of colour, but also provide much needed shade in Australia’s harsh summers while also letting light in during winter. Jacarandas thrive in Australia’s coastal cities, where the warm temperatures provide ideal growing conditions. However, it is possible to grow them in cooler regions with a bit of careful planning.
As with any tree, there are three key steps to growing your own jacaranda tree:
- Select the optimal growing position for your tree, keeping in mind the mature height and spread of the crown.
- Choose the right planting method i.e. planting from seed or propagating. When using plants that have been raised in pots, planting pits should be at least two times as wide as the width of the root ball, and no deeper than two times the height of the root ball. The top of the root ball after planting should be flush with the finished soil level in the pit.
- Maintain your tree as needed. Watering is essential as a guide, apply water once a week in the first 4 weeks after planting, once every 2 weeks for the next 8 weeks, and then once a month until the tree is 3 years old. When watering, thoroughly wet the root system.
Below we walk you through each of these steps to cover everything you need to know to grow a jacaranda tree in your garden.
1. How to select the optimal growing position for your jacaranda tree
Choosing the right position for your jacaranda tree is vital for ensuring your tree grows well. Jacarandas are large trees, so they need plenty of space. But they also need plenty of sunlight and a sheltered position while they are young so they can establish themselves. Below we outline the things to keep in mind when selecting the optimal growing position for your jacaranda tree.
Being native to South America, jacaranda trees grow best in subtropical, tropical and warm temperate climates. This makes them a popular choice for home gardeners in Australia’s warm coastal cities including Brisbane, Sydney and Perth. However, it is still possible to grow jacaranda trees in cooler climates, provided you select a sheltered, sunny position. While young plants are frost sensitive, established plants can tolerate light frost and short periods of temperatures just below zero degrees Celsius, so with enough care you may be able to grow them in cooler inland areas. However, it is important to note that jacarandas planted in cooler climates tend to grow more slowly and may not reach the same size—or flower as well—as those planted in tropical regions.
When thinking about where to plant your jacaranda tree, it’s important to keep in mind the amount of sunlight it will get, as well as the size of the space. Jacarandas thrive in sunny sheltered positions, so plant your jacaranda tree somewhere it will receive full sun but still have protection from the wind. Ideally, jacarandas require 6 – 8 hours of sunshine per day. This will ensure the tree grows well and develops healthy, vibrant flowers year on year.
As well as sunshine, jacarandas need a decent amount of space to grow well. They’re large trees and can mature to over 10 metres in height with a broad canopy, so it is important to choose a position that leaves them plenty of room to grow. They make a great addition to gardens if planted on open lawns or along driveways where they have plenty of room to branch out. The famous jacaranda tree in the University of Sydney’s main quadrangle is a prime example of how a lone jacaranda tree planted on a lawn can transform a garden.
When selecting a location for your jacaranda tree, it is also important to keep in mind that the trees will shed leaves, seed pods and flowers. Both the leaves and flowers can easily pass through gutter guards, so it is a good idea to keep them away from roofs and drains. And as beautiful as the flowers look on the ground, keep in mind that they can become slippery when wet, which can be an issue if the tree is planted next to a stone or concrete pathway.
Jacaranda trees grow best in rich, well-drained soil with a slightly acidic pH. While they will tolerate most soils, they are particularly fond of sandier soils and you should avoid planting them in soil that gets easily waterlogged—such as heavy clay soils—as this increases the risk of root rot or fungal problems. As with most trees, it is a good idea to prepare the soil before planting with a combination of good quality compost and/or tree planting mix.
2. How to choose the best planting method
As with most trees, there are three main ways to grow a jacaranda tree: from seed, from a seedling or from a cutting. Each method has its own pros and cons, so it is important to choose the method that will work best for your climate and level of gardening experience. Below we describe how to plant a jacaranda tree using each of these three methods.
Growing a jacaranda tree from seed
There’s nothing quite like watching a tree grow from a tiny seed all the way through to established plant. Although many gardeners opt to grow vegetables and flowers from seed, far fewer attempt to grow trees this way. Here’s how to do it:
Collect seeds. Jacaranda seeds are readily available from nurseries and online retailers. However, if you would prefer to collect your own seeds, make sure to pick seed pods directly from the jacaranda tree and not from the ground. Jacaranda trees produce seed pods throughout spring, from October to November and this is the best time of year to germinate the seeds. To collect the seeds simply crack the seed pod open to remove the seeds.
- Soak the seeds. Once removed from the seed pod, soak the jacaranda tree seeds in water for 24 hours. Soaking seeds helps to speed up the germination process by softening the seed’s protective outer coating.
- Plant the seeds in seed raising mix. Place the soaked jacaranda tree seeds on a bed of soil or seed raising mix in small pots or seedling containers. Cover the seeds with a light layer of soil (no more than 1cm) to keep them in place.
- Keep seeds warm and moist. Keeping the seeds warm and moist is essential for encouraging germination. Using a spray bottle can be a good way to keep the soil moist without disturbing the seeds. To help prevent the seed trays from drying out, place the pots in a warm but shaded position.
- Wait for the seeds to germinate. In the right growing conditions, jacaranda seeds take between 14 and 28 days to germinate. The ideal germination temperature is between 20 – 24 degrees Celsius.
- Care for the seedlings. Once germinated and sturdy enough, transplant the seedlings into pots. Seedlings should be left to grow for around eight months before being planted in their final growing position.
While growing a jacaranda tree from seed takes more time than buying an established plant, it can be much more rewarding to watch your tree grow from seed. However, it is important to keep in mind that plants grown from seed can be more variable in their flowering, in some cases taking many years to flower.
Growing a jacaranda tree from a seedling
By far the easiest way to grow a jacaranda tree is to buy a seedling or an established tree from your local nursery. This method will also ensure you have the best chance of growing a tree that will flower consistently, as most nursery bought jacaranda trees will have been grafted from cuttings.
When the seedling is ready to go into the final planting position you’ve chosen for it, simply dig a hole as deep as the tree’s root ball and twice as wide. Place the tree inside, backfill with soil and apply a light layer of mulch around the seedling to help keep the soil moist. Water the tree well after planting to avoid shocking the plant.
Growing a jacaranda tree from a cutting
As with other trees, it’s possible to grow a jacaranda tree from a cutting by following these simple steps:
- Cut a small section (~30-50cm) of healthy branch that is roughly 2cm in diameter. This will be the branch you take your cutting from.
- Take a cutting roughly 10 centimetres long from the end of the branch. The cutting should contain at least three healthy buds and new shoots that have grown past the bark. Make sure to take the cutting just above where the leaf grows from the stem, and cut on a diagonal. Cut just above the point where the leaf grows from the stem.
- If you want to speed up the growing time, you can opt to dip the cutting into rooting hormone before placing the cutting in its growing spot.
- To encourage the cutting to develop roots, either place the cutting into a jar of room temperature water, or a container filled with a soilless growing medium such as perlite or vermiculite. You could also use a potting mix enriched with perlite, but ensure it drains well. Place the cutting in a warm location that receives indirect sunlight. The cutting should develop roots within 2-3 weeks.
- If you choose to grow your cutting in water, you will need to transfer it to a container of potting mix once the roots have reached around 2cm.
- Let your cutting grow for around eight months to become established and harden off before transplanting it into the garden. During this time keep it in a warm position with adequate sunlight and ensure the soil stays moist but not waterlogged.
3. How to maintain your jacaranda tree
Like most trees, jacarandas require a little bit of tender loving care to establish themselves and stay healthy. However, they are relatively low-maintenance trees and become even more so over time. Below we outline some important jacaranda maintenance tips to ensure your new tree thrives.
Young jacaranda trees require regular watering to encourage growth, however they don’t like to be left in waterlogged soil. A good rule of thumb is to water them only when the top 50mm of soil has dried out. Overwatering reduces vital soil oxygen necessary for root growth.
In addition to their flowers and attractive foliage, jacarandas are loved for their graceful spreading canopy. Fortunately, no pruning is required for the tree to attain this shape, as the branches will grow semi-horizontally in a spreading pattern by themselves. When the tree is very young (less than 2 metres tall) you can prune away side-shoots, to concentrate growth on one central trunk. However, once the tree reaches 2-3 metres tall, you should allow the tree to develop its canopy naturally. If you prune these shoots, you risk encouraging the tree to grow shoots upwards which can alter the tree’s shape.
Your jacaranda tree shouldn’t need fertiliser to encourage growth. However, if your tree is growing particularly slowly and you want to apply some fertiliser, avoid using a nitrogen rich fertiliser as this can prevent the tree from flowering.
Keeping the base of the jacaranda tree mulched while young can help to prevent the soil from drying out. Ensure you leave a gap between the trunk and the mulch to allow good airflow and moisture to sink into the soil. Mulch should be no deeper than 75mm.
Jacaranda tree FAQs
Below we answer some of the most common FAQs about jacaranda trees.
#1 Are jacaranda trees a weed?
Because jacaranda trees are not native to Australia, many people wonder whether they are considered a weed or pest species. While there have been instances of the plant ‘escaping’ in South Africa and outcompeting native species, this hasn’t been a problem in Australia, and they are generally not considered to be a weed of economic importance.
#2 Will my jacaranda tree survive frost?
Being a tropical plant, jacarandas grow best in warm, relatively humid climates where they aren’t exposed to extreme temperatures. As a result, they don’t grow well in climate zones that regularly experience heavy frosts through winter. Having said that, mature jacaranda trees can handle light frost so you can still grow them if you live in a cool inland area that sees cold winters. If you choose to do so, ensure you protect your young jacaranda trees—particularly those less than two years old—by covering them up when frost is forecast, as these are particularly susceptible to frost damage.
#4 Are there other varieties of jacaranda tree besides the blue jacaranda?
Jacaranda mimosifolia—or blue jacaranda as it’s often called—is by far the most common form of ornamental jacaranda. However, there are 49 other species of jacaranda in the same botanical family found throughout South America. Two other rarer jacarandas that make a beautiful addition to the home garden include:
- Jacaranda mimosifolia alba, which is a rare white jacaranda that is also known as White Christmas as it typically flowers in December in Australia.
- Jacaranda mimosifolia Bonsai Blue, which is a dwarf jacaranda tree variety that produces the same foliage and flowers as the standard jacaranda, but grows to a maximum height of only 2.5 metre
#5 Do jacaranda trees stop native plants from growing around them?
Because the jacaranda has a large, spreading canopy, it will create a sizable patch of shade which can prevent plants from growing beneath it. If you do want to grow other plants underneath the jacaranda, choose plants that favour shady positions.