From canopies of gold and russet, to the evocative crunch of leaves underfoot, there’s no more magical place to experience the changing colours of Autumn than the Blue Mountains Botanic Garden Mount Tomah.
Let’s face it - in Sydney, Autumn can be somewhat of a non-event, a mild and largely forgettable extension of the lazy days of Summer that simply eases us into the coming chill.
But in the loftier, cooler altitudes of the Blue Mountains, Autumn is the ultimate showstopper, announcing itself with a dazzling display of gold, red, orange, russet and brown as the leaves of deciduous trees turn and tumble, revealing the bare armature of Winter.
This seasonal glory presents a little touch of the Northern Hemisphere, reminding us of the potential for snow in exotic lands and sending visitors into an Insta-frenzy of selfies amongst the blazing palette, offset by the evergreen native bushland and misty blue horizon that lends the region its name.
What causes Autumn leaves to change colour?
There’s science behind this beautiful phenomenon – so as you wander along pathways lined with stunning Autumn colour, consider just how complex Mother Nature is.
It’s all about protecting the tree from the coming Winter: as the chill sets in and the days shorten, the amount of sugar generated by photosynthesis drops off, causing the green chemical chlorophyll to break down. However, other chemicals within the leaf are then revealed: yellow flavonols, orange carotenoids and red to purple anthocyanins, with the mix of compounds varying between species.
As the tree becomes dormant, so less water reaches the leaves, trapping the chemicals remaining in the leaves. These gradually break down, changing the colour of the leaf before it falls to the ground.
Temperature, light and water supply all affect the duration and degree of Autumn colour – and with rain said to increase the intensity, we could be in for a bumper ’leaf peeping’ season after a soggy summer in the Blue Mountains.
With its lovingly-curated precincts and mature plantings, there’s no more idyllic location to admire Autumn colour than the Blue Mountains Botanic Garden Mount Tomah.
Incorporating original plantings from its former life as a flower farm owned by the Brunet family with new and rare cultivars of dozens of colour-changing species, the Garden is a picture from late March to mid-May, ablaze with hues of red and gold as well as the pastel blooms of camellias, late dahlias and asters.
With more than 365 specimens, the most notable of the Gardens’ deciduous trees are from the genus Acer, commonly known as maples. The expansive collection includes 198 species and cultivars, including 141 Japanese maples ranging from dwarf species to soaring canopies.
But it’s not just maples that create the patchwork of Autumn hues – there are dozens of other deciduous trees lining the pathways that weave through the Gardens.
On the Plant Explorer Walk, for instance, the big, buttery leaves of the Blunt-lobed Spice Bush (Lindera obtusiloba) carpet the ground, contrasting beautifully with the grey basalt rocks.
Meanwhile, for Ian Allan, Acting Curator of the Blue Mountains Botanic Garden, the most impressive deciduous conifer in the collection – found along the Plant Explorer Walk – is the False Larch (Pseudolarix amabilis), a species which can grow over 30 metres in height.
Another towering species is the Dawn Redwood (Metasequoia glyptostroboides), several of which stand as sentries over the main carpark at the Gardens. There is also a cluster in the Brunet Garden, with the golden canopy creating an iconic photo from the Visitor Centre Viewing Deck.