April is the month for autumn and fall colours in Australia. While the Northern Hemisphere is dealing with the last snow flurries and the beginning of spring rains, Australia is experiencing longer, cooler nights and shorter days. Concurrently, Australian deciduous trees display their colourful Autumn finery.
What Causes Leaf Colour
Despite fanciful children’s stories of Jack Frost painting the autumn leaves, the colours are actually in the leaves all year round. Travel Insider quotes Simon Rickard, plant expert, and botanical tour guide, as saying that in areas where there is a sharp climate change in autumn, the cooler weather signals the trees to withdraw the green chlorophyll from the leaves, revealing the glorious colour that was there all the way along.
Colourful Trees in Australia in Autumn
Sydney, and other areas of New South Wales, are marvellous places to visit if you wish to view a colourful Australia. The colour comes from native trees and from imported ornamental trees that are planted in various yards and gardens. Imported trees might include oaks, maples, ash, and elm, just to name a few colourful imports.
Australia has few cold-weather climate deciduous native trees. These include:
- nothofagus gunnii, or fagus, a native beech tree that puts on a magnificent display of colour before dropping all its leaves. It can be found in Tasmania.
- Amelia azedarash, or white cedar. While not as flashy as some of the European short day/cold weather deciduous trees, their leaves turn a soft yellow and fall off. They can make an impressive ground carpet. This is also the time when their fruits will ripen, creating a feast for native birds.
- Toona Ciliata, or Red Cedar. These are rainforest trees that were highly prized for the red tone of their wood. Unfortunately, this caused them to be harvested extensively in Australia, diminishing the local population. They are sensitive to drought and cold. Conversely, these trees are classified as an invasive nuisance in east Africa.
Australian Colorful Trees
Not all deciduous trees in Australia drop their leaves in April or May. In the warmer areas, there are trees, such as the Queensland Bottle Trees, brachychiton rupestris, which blossom at the beginning of winter, have green leaves during the rainy/cool season, and put on a beautiful display of red leaves in the spring, shortly before the hot season.
This reversed deciduous behaviour helps the trees to collect all the moisture possible during the rainy season and reduces water loss through leaf respiration.
Imported Deciduous Trees for Color
Living in Australia doesn’t mean that you have to give up Autumn colour. Deciduous trees from north of the equator can and do adapt to Australia’s southern hemisphere climate and soil. It is a good idea to be aware of which trees are likely to be classified as “invasive” in Australia.
Some trees are too happy with the climate, even though they might ordinarily be considered useful. Olives, olea europea, fall into this category. They spread quickly by seed and can have the unintended effect of crowding out native plants.
With that said, you can absolutely have olive trees as part of your cultivated area. Just be diligent about harvesting the fruits – which you will probably want to do anyway.
Chinese Pistachio, pistachio chinensis, grows to be about four feet tall and has beautiful red and gold foliage. However, even though it is frequently listed as an option for fall colour in Australia, it is also classified as a weed in New South Wales. The ACT classifies it as a “sleeper weed.”
Chinese Tallow Tree, Triadica Sebifera, sometimes sold as sapium sebiferum, also shows up as an invasive species on many lists, including in the United States. It was originally introduced as an oil-bearing plant (note the name, Tallow tree), but is now primarily grown as an ornamental. It is hardy, spreads both by seed and by root, and can quickly take over a forested area where it can crowd out native plants.
Flowering Crab Apple, malus sylvestris, is a marvellous small tree that is acceptable just about anywhere. (Just in case you were beginning to think that all trees from other places are invasive.) Crab apple trees add colour to your garden all year round. In spring, they have pink or white blossoms; in summer they put on fruit. Depending on the variety, some types of crab apple can be used to make jams or jellies. In autumn, depending on the variety, the leaves turn an attractive gold, red, maroon, orange, or bronze.
Fall colour is an integral part of your garden. In addition, deciduous trees can make extra work with their seasonal leaf fall. However, if you are dedicated to composting, those leaves can add valuable nutrients to your compost heap.