Gum Tree Eucalyptus gomphocephala

The species name gomphocephala means club headed, and it refers to the fat woody bud caps that sit wider than the flower base, the quickest way to pick a Tuart at close range. This is the big limestone country eucalypt of the Swan Coastal Plain, with thick rough grey fibrous bark, a heavy spreading crown of genuine forest scale, and cream flowers that pull in bees and honeyeaters. It is planted for farm windbreaks, coastal shelter and park shade, where its bulk is an asset rather than a liability.

Limestone sand, and what rich soil does to it

Its home ground is the coastal limestone belt of south western Western Australia, so alkaline sand, salt laden wind and long dry summers are normal conditions rather than a challenge. That makes it a sound choice for Perth and the south west, coastal South Australia and dry exposed sites on similar ground elsewhere. Full sun, and once the roots are down it asks for very little water. In a shelterbelt, space it for the crown it will eventually carry rather than the plant in front of you, because a crowded tuart draws up thin and loses the low branching that makes it useful as a windbreak.

Soil chemistry decides a Tuart, not care. It evolved on deep sand over limestone and it is one of the few eucalypts in this range that genuinely wants alkaline, free draining, low organic ground. Put it into acid eastern clay, or into a bed built up with rich compost and manure, and it yellows between the leaf veins, stalls at head height and never builds the crown that was the reason for planting it. Feeding harder makes that worse rather than better. If you are outside limestone or coastal sand country, plant it on a raised bed of coarse sand with lime worked through, or choose a species that suits the soil you have. Scale is the other consideration, since this is a forest tree with heavy limbs that belongs well clear of buildings, sewer lines and anywhere vehicles sit.

Three Western Australian trees for three different sites

Two other Western Australian species in this range solve different problems. Flooded gum comes from the same coastal plain but holds the low, damp clay that Tuart refuses, so on a wet paddock corner it is the better answer. Flat topped yate goes further again, tolerating both waterlogging and salt in the soil. Tuart is the choice for deep, dry, alkaline sand and coastal wind, and it makes the most substantial and longest lived shade tree of the three. The bark tells them apart at a glance: rough grey fibre all the way up on Tuart, a short rough stocking under smooth pale limbs on flooded gum. If you have room for one large tree on dry sand, this is the one to plant. See other large specimens in feature trees.

Get the trunk right before head height

Train a single leader early. Shorten competing stems in the first few years rather than cutting them off flush, lift the canopy gradually as the trunk thickens, and get the structure right before the tree is above head height, because large pruning wounds on a mature tuart are slow to close. Late winter is the window. Feeding is barely necessary on sandy ground. Two springs of a native blend will see it away, along with trace elements if the leaves yellow between the veins on very alkaline sand. Keep turf away from the trunk, mulch out to the dripline, and avoid running summer irrigation against the base of an established tree.

Choosing a size

This plant is available in 5 sizes, from 200mm up to 90L, priced from $29.95 to $479.00 per plant. The size shown is the pot the plant arrives in, which is the rootball, not the height of the plant. The smaller pots hold younger plants that cost less each and establish quickly, which suits hedges, screens and mass planting where the plant count adds up. The larger sizes carry several more years of growth on the farm and give height and presence straight away, which is what you want for a single feature position or a screen that cannot wait. Not sure which to choose? Read our guide to Australian native trees for shade.