Summer brings sunny days and outdoor fun, but the heat can also be a challenge for our gardens and us gardeners. Trees are a great way to cool down our outdoor spaces and provide shade from harmful UV rays. However, choosing the wrong tree for an urban environment can lead to costly, long-term problems. Understanding the best trees for your space is key to creating a sustainable and comfortable garden.
Selecting a tree takes careful consideration, with the temperatures only getting hotter selecting native species is a great way to increase your changes of long-term success. You don’t want something that will get too big for your garden either and you want the tree to give you a little more than just shade – so here are a few species I like to use when designing a space.
Corymbia ficifolia the red flowering gum is one of the most popular eucalyptus cultivars in the world, it’s a small to medium sized relatively fast-growing tree that will give not only shade but also incredible hot red flowers in summer. Due to the tree’s popularity, there are a lot of varieties so a wide range of sizes, from dwarf forms to grafted ones and colours from pink to orange. This tree will cope with full blasting heat and a variety of soil types as well, so it really is for any type of gardener. The only place I would be wary of using this is next to bush land as eucalyptus are terribly promiscuous and easily hybridise so you could inadvertently create an undesirable hybrid that might takeover.
Agonis flexuosa the peppermint tree is a medium size tree with a lovely weeping habit. This tree responds well to pruning so can be used in a smaller garden and over time the trunk develops to a thick ornamental shape so can be used with a similar effect to an aged olive tree. There are a range of varieties and cultivars with dwarf forms available and even deep purple foliage which can be very striking in the heat of a blinding summers day. Agonis will grow in most soils but does benefit from watering whilst establishing and this will also speed up the growth if continued past establishment. As the name suggests the leaves smell strongly of peppermint if crushed and the tree gets covered in striking small white flowers in spring and summer.
Banksia makes for an excellent tree in so many gardens thanks to its adaptability to grow in poor free draining soils. The flowers are not only striking but an excellent food source for native birds such as honey eaters and cockatoos. The bull Banksia, B. grandis has an irregular open shape that adds character to a garden space with its large-toothed leaves and special large yellow flowers. The firewood Banksia, B. menziesii has a similar wide canopy for shade but less unbalanced than B. grandis and a spectacular two-toned colour to the flowers adding even more interest. Banksia can be slow growing, but their character adds atmosphere to a space and an superb aged feature. Don’t try to speed the process up with fertiliser as they can be susceptible to nitrogen and phosphorous toxicity which can lead to rapid decline and sudden death.
Harpullia pendula the Tulipwood tree will give your garden a sense of the tropics with its glossy green leaves and dense canopy. This tree can get up to 10 meters tall but don’t expect this in WA – it will more likely be topping out at 7 meters when fully mature. As a tropical plant it can take a lot of sun but will need some additional watering in the hottest of days when establishing it, after that its surprisingly drought tolerant as well as frost tolerant too. This tree will not only give you dense shade but add interest as gets a beautiful bronze tinge to the new growth and there is an inconspicuous flower in summer, but this is quickly followed by bright orange seed capsules that catch the eye.
