Two farms, two climates, one range: what the growing ground does to a tree

Ravensbourne is 40 acres at 750 metres, in cool subtropical highland country north west of Brisbane near Toowoomba. Rich volcanic soil, 2,053 trees, and real winter frost. Donkin Farm is 40 acres at Utchee Creek in the wet tropics of Far North Queensland near Innisfail, more than 1,200 kilometres north, with 4,048 trees. Between the two farms: 6,101 trees, 119 production lines, 65 species in 38 genera.

Both farms supply the whole range into Queensland, New South Wales and parts of Victoria. So the Waterhousea on your plan may have been raised in frost or in the wet tropics, and the fair question is whether that makes any difference by the time it stands on your site.

It does, though not in the way most people assume.

The two grounds give a tree different instructions

Ravensbourne gets a proper winter. Growth stops for a real period each year, and a tree made to stop does several things at once. It hardens the wood it made that season, sets buds, and lays the next season's growth down in shorter increments. The result is shorter internodes, more branching per metre of stem, a tighter denser habit, and bark that sets harder. Leaves tend to be smaller and thicker. The cost is time: the same species takes longer at Ravensbourne to reach a given calliper than it does in the north, and there is no way around that.

Utchee Creek is the opposite instruction. Warmth and rain through most of the year mean growth is close to continuous, so trees come on quickly, hold more leaf, and make longer internodes with a more open frame in youth. What that country also builds in is wind. Cyclone season in the Far North runs roughly November to April, and a tree that has grown up in that ground has been shaped, staked and root pruned with weather taken as a given rather than an exception.

The same species, coming on two ways

Stand a highland and a tropical example of the same species side by side and you can read the difference without a tape.

• Brachychiton acerifolius. The cold gives it a clean, definite pause and a hard leaf drop. In the north it holds leaf longer and behaves closer to semi-evergreen. Frost grown trees carry a stiffer, more upright frame with tighter branching.
• Cupaniopsis anacardioides. Tough in both grounds. Highland trees are denser and more compact with smaller, harder leaves. Northern trees are faster and more open, with larger foliage.
• Ficus. Vigorous anywhere, exceptional in the north. The highland cold puts a brake on them, and a Ficus that has been slowed is an easier tree to place and to live with.
• Waterhousea floribunda. Wants water and gets it at Utchee Creek, where it makes long weeping growth quickly. Highland stock furnishes lower and closer with smaller leaves, which is what you want if the tree is going into a hedge line rather than standing alone.

What that means once the tree is on your site

Here is the honest part. For most jobs the growing ground matters less than the handling. A tree that has been root pruned in stages through its production life, dug with a four concave blade spade so the ball follows the roots, set into a hessian lined steel basket on eight tensioned straps, carried under shade cloth on yokes and craned into place without being dropped, will establish. One that has been rushed will not, whichever farm it came from. Water in the first year decides more than provenance.

Provenance matters at the edges, and the edges are worth knowing.

• A tropically grown tree going onto a genuinely frosty site has never been asked to shut down. It will want shelter through its first cold season, and often its second. That is manageable if you plan for it and unpleasant if you do not.
• A highland grown tree going into warm coastal or tropical country simply grows faster than it did at the farm. There is nothing to manage.
• Leaf size and internode length even out within a couple of seasons on the new site. The tree starts obeying the new ground, not the old one.
• What does not even out is the frame the tree already carries. Trunk taper, branch height, the angle of the main limbs and the shape of the head were built in years ago. That is the thing to look at, and it is why we walk the lines and pick individual trees for a job rather than filling an order from a number.

Why we run two grounds rather than one

Two climates 1,200 kilometres apart give the range depth that one could not. Species that sulk in frost thrive at Utchee Creek. Species that want a cold pause and set better form for it are grown at Ravensbourne. A few, tuckeroo among them, do well in both, and having them in both grounds means we can offer the same species with a different habit depending on what the site is asking for.

For the wider picture of where Australian growers are and what they grow, HortOS publishes nursery industry statistics drawn from growers in every state.

It also means a job specifying five species is not held to whatever one paddock happens to hold. Everything is ex-ground and price on application, and both farms use the same certified basket system: 1.4 m baskets for trees of 3.5 to 5.5 metres, 1.6 m for 6 to 8 metres, 1.8 m for the largest stock.

There is more about each farm at Ravensbourne and Donkin, an overview of how the two work together at our farms, and the full list at all trees. Tell us the site and we will tell you which ground grew the tree that suits it.