Effort and resources put into site preparation will enhance establishment success and thus save time and money in the long run. Most of these steps add more value the poorer or heavier your soils are.
1. Location, location: the right tree for the right location
It is critical to select the right tree species for your location. For instance, most large, spreading trees of 20m in height or more should be planted 10m or more away from buildings. Specie and soil type is another important factor to consider. In general, deciduous species are most suitable immediately northwest, west and southwest of structures in southern Australia to allow for winter sunshine, deep, summer shading and fire protection. Deciduous species can absorb large quantities of water, especially if irrigated, and thus form a “water wall” between your house and a potential fire. Oaks, elms, maples and beeches, for example, are good for this. Sun shading in summer is of particular importance and has a significant effect on dwelling temperature. Similarly, on farms, deep shade, from say, spreading bur oak or Algerian oak (Quercus macrocarpa, Q. cannariensis), reduces animal stress. Windbreak and screening species like casuarinas, Blackwood, lightwood, hakeas, callitris, pittosporum and carob are effective 20-100m or more from buildings depending on space.
2. Site Preparation
i. Dig a hole 2-3 times the root ball diameter e.g. a minimum of 80cm for a 40cm ball, 1.2m in heavy soils
ii. Dig only as deep as the root ball
iii. Taper the wall so it slopes gently upwards towards the perimeter
iv. Mound a berm 75mm high beyond the basin perimeter to dam water.
v. Add around 10ml of water crystals for dry areas or fast draining soils
3. Root Ball Preparationn
i. Water your root ball to capacity before digging
ii. Cut away the plastic or woven bag with a knife on site
iii. Remove all kinked or misshapen roots just above the bend both at the base and on the edges of the root ball
iv. With a spade slice vertically several times down the sides of the ball about 5cm deep
v. Remove or trim matted roots with a spade or handsaw at the base if necessary.
4. Planting and Filling
i. Place in basin and ensure the surface of the root ball is level with the surrounding ground
ii. Thoroughly break up excavated fill and shovel in around root ball (Never cover the root ball surface with soil.)
iii. If your soil is poorly drained (heavy clays) or nutrient deficient, see below.
i. For 1 meter crown diameter trees, fill the basin with 40-80 litres of water fortnightly over summer and about half
this in spring and autumn during the first season. For smaller trees 20 litres is sufficient at the same intervals
ii. Preferably hand water your trees the first season so that you observe moisture levels and avoid over watering,
which can occur with automated irrigation systems.
i. Mulch your trees with straw, silage waste or similar broken down material 5-10cm deep over the entire basin area
to retain moisture, suppress weeds, moderate soil temperatures and add organic matter
ii. Never pile mulch against the trunk or trunk base
iii. Avoid green manures like fresh grass etc. as this will rob nitrogen from the growing area
i. Stake your tree if protection from pests and mechanical damage might occur or the site is especially windy
ii. Drive the stakes into the subsoil beyond the root ball
iii. Loosely tie the tree with cloth of hessian so the trunk can flex naturally
iv. Remove the stakes after the first season if practicable.
8. Poorly drained soils
i. If you’re planting in heavy clays or other poorly drained soils, followed the above steps, but position the root ball
so as to leave it 1/3 above the surrounding ground level
ii. Dig the hole 3-4 times the root ball diameter and 2/3 as deep as the root ball with gently sloping sides so as to
allow roots to spread up and out above the hard clay wall instead of girdling around it
iii. Set the root ball in the hole standing 1/3 above ground level
iv. Backfill the well broken down soil into the hole level with the ground
v. Thoroughly mix the remaining heavy fill with introduced sandy or silty loam and shovel this material onto the
top of the basin
vi. Camber this mix from the root ball down to the ground level below the berm
i. Allow your tree to grow over the first season before fertilising if at all
ii. If soil tests and observation demonstrate nutrition deficiencies sprinkle appropriate fertiliser on the surface and
perimeter of the root ball once the tree has demonstrated some growth
iii. Mounding fertiliser will help delay application and provide a longer release of nutriment or purchase slow