Ensuring industries best practices are performed without compromises.
Most negative influence on orchard performance
Not really any. Ability to hang fruit on trees longer than comfortable with to meet exporter timing is probably the only thing but is not a huge impact as tree’s are in good health.
General management
Pollination, pruning and fertiliser planning is contracted out. Remainder of work is completed by owners and one part time staff member.
Tensiometers are installed and serviced on a regular basis to ensure the most accurate data is informing orchard practice and industry weather stations are utilised to inform best practice decisions on irrigation.
Soil temperature is believed to be important, particularly over spring. Herbicide is used to spray out about a 30cm strip around drip line. This is often bare soil and captures sunlight well to warm soil.
Regular mowing is also carried out, particularly in spring to keep grass short and maximise sun capture to warm soil.
Canopy management
Tree spaced 10m X 10m
Managed in rows
Max height of trees is 6.5m
Trees pruned to allow light into the middle of tree but no particular shape targeted. Try to give each limb enough space to get good light and get good light right through tree including the middle and sunlight onto the soil under the tree’s. This supports good flowering and increases the potential for new growth from the middle of the tree all the way to the edge. This maximises productive area and provides options to prune back to reduce canopy width and height while still having fruiting wood on the limb after cut.
Trees are structurally pruned twice a year with larger cuts made in spring or autumn depending on crop remaining on trees. Limbs are selectively removed to generate productive/replacement wood and maintain light onto these limbs. Also to ensure good light distribution through the entire canopy. About 30% of the canopy is removed each year.
Flower pruning is used on excessively flowering trees. Very rare to prune fruit off trees as flower pruning generally does a good job to correct crop load. Trees will be revisited if trees looking too stressed or carrying a heavy crop post flower pruning and fruit will be removed if over cropping. Regular structural pruning helps regulate crop loading as well by maintaining different aged wood and encouraging replacement wood.
Crop load is assessed in stages with intervention made if not enough leaf is coming through. Possible that two rounds of flower pruning and 2 rounds of fruit pruning carried out on a tree if it continues to look stressed. Important to balance new fruit with flush, etc.
Heavy structural pruning took place over two seasons two years apart to establish a good structure to work with going forward. This two year gap was chosen to ensure cash flow was maintained throughout the restructuring.
Soil and soil moisture management
Orchard is predominately sandy loam.
Leaf litter, avocado pruning and shelter pruning are all used to mulch trees.
Soil moisture is monitored using tensiometer at two sites with readings of -30kPa for 10cm probe which is used as trigger for irrigation in summer and autumn. A trigger point of -25kPa is used at full-flowering in spring. If 30cm, and 50cm soil moisture readings keep declining beyond a month, a longer irrigation may be applied.
The orchard is 100% irrigated with over-canopy micro sprinklers used for both irrigation and frost protection year round.
At peak summer it is common to irrigate for 6 hours per irrigation event once a week using sprinklers with a 12-14m diameter that deliver 120l/hr (4.3mm per irrigation event). Bore available with consented water.
Sprinkler heads that distribute different volumes over different areas are chosen based on soil type, tree size and age, health, topography. Irrigation is seasonally adjusted as well.
Pump pressure and flow characteristics are checked twice a year (Prior to main frost risk period and prior to main irrigation period) with ongoing inspection of pipework on orchard. Sprinklers heads are monitored regularly and serviced if required to maintain proper function.
Pollination
Pollinizer species include Bacon, Ettinger, Zutano, Fuerte and Edranol at a percentage of 10-12%
Hives are brought onto the orchard at about 10 – 20% flowering at a rate of 9 hives per hectare. Hives are located evenly through block.
Soil and fertiliser application
Soil and leaf tests are carried out once a year in April. Flower testing is carried out if there are concerns about boron values.
A consultant provides a fertiliser plan based on test results and crop loading.
The majority of fertiliser is applied by ground application but foliar application is also used. Ground applications are assessed based on various tree characteristics e.g. tree crop load, health, canopy volume. Fertiliser applications may also be split into two applications over the same time period on sick or stressed trees to maximise uptake from a potentially limited root system and to avoid shocking the roots too much. Lower yielding trees receiving less fertiliser.
Low biuret urea, magnesium sulphate and stimplex foliar sprays are applied through winter to maintain leaf colour. Boron and zinc foliar applications may also be made prior to flowers opening depending on soil and leaf test results.
Boron fertilisers are applied as ground application and foliar every year.
Lime and Gypsum (Calcium) fertiliser is applied every year
Fertiliser in some form is applied 12 times a year.
Shelter
Five small blocks in total are well protected from wind effects and shelter helps retain heat. Trees are used for shelter on all boundaries and are a mix of Casurina, Lusitantica and Banksia. All shelters are 6.5m high. Shelter trees are maintained each year at the completion of flowering.
Tree health management
Trees are injected twice a year with phosphonate with root testing conducted to verify application has been successful. All trees are injected in late spring/early autumn and sick or stressed trees are reinjected in August (winter).
Frost protection
Over canopy sprinklers are used for frost protection. A trigger point of 4°C is used in spring to ensure flowers are protected when most vulnerable. In winter a trigger point of 1.5°C is used to avoid excess water application.
