Pruning for profitIndustry Best Practice
With winter approaching, it’s time to start thinking about winter pruning with AgFirst’s Craig Hornblow explaining some key pruning concepts to help improve the profitability of your orchard.
Clear targets and simple, repeatable rules
The old saying ‘speculate to accumulate’ has never been truer in these trying times. What do we mean by this? There are many strategies to assist the orchardist when market returns are down, however the one we favour the most is to grow more fruit in the better paying count sizes and more fruit with better colour to maximise market returns. With many years of fruit size monitoring recorded on OrchardNet®, growers have plenty of data for measuring if a particular variety is on target to achieve optimum market sizes. Talk to your marketer or packer and ask what count sizes are paying the best money. Analyse your market returns and then write this into your next season’s goal.
Attention to detail is required to capitalise on ‘growing to market’ and growers can instigate bud counting and more detailed winter pruning to reduce the numbers of inferior fruit that don’t make these premium fruit sizes and colour standards. Australian growers have come a long way with long pruning, and most now agree that targeting branches pointing at the ground instead of the sky has reaped increased production yields consistently for all. The next stage is to increase the quantity of premium fruit produced and this takes more skill and time.
What can we learn from the newer formal growing systems that rely on wire for laying branches on to? The newer planting systems with branches laid horizontally on fruiting wires makes pruning and spur/bud removal very simple. Staff don’t need to space branches as this is already taken care of as branches are laid onto wires at set distances apart. All that is required on these systems is to remove surplus growth and space buds.
Branch spacing involves several thought processes. First up, how many branches are in your tree. If your tree is 3.5m tall and has filled its allotted space, then reviewing if you have too many branches every year is very important. Think about the new formal two dimensional (2D) type systems and how regimented their branch spacing is. Now is the time to check that each branch has plenty of space from not only branches above and below it from the same tree, but also from neighbouring trees. Look for the biggest branch that is growing the most vigour and if this is cut out, can another branch above it or from a neighbouring tree take its place. The beauty of high density plantings is also that often you can remove one or two branches a tree and they won’t be missed because you have so many other branches to take their place.
By cutting out the biggest branch causing the most shading, you are ensuring future production is assured from buds further down the tree. Target branches near the top of the tree as they produce shade that affects buds low down. We are aiming to get satisfactory light penetration right through the tree from top to bottom. A simple rule we have used in Future Orchards® is that if you can’t see 3-4 rows through your canopy (once in leaf), then your trees are probably too dense and need more branches removed. Also, in winter, if there is more low coloured fruit left in the bottom of the trees, then this indicates not enough sunlight is getting down to them. Removing more branches may help this.
The spacing between branches can depend on how long you leave the branches above and below. In the early years of setting up trees, branch length can be as long as 1-1.5m or more. As trees age and these longer branches tend to collapse inwards toward the leader, which can cause more shading, the need comes to start removing some of them or shortening them. Beware that shortening can be a very sharp scalpel; branches that were growing quietly and calmly can be reinvigorated and throw copious amounts of vegetative growth upsetting the whole balance of the tree. So, only shorten branches if you are confident these shortening cuts won’t invigorate the tree. Delaying the time of shortening cuts to when fruit is on the trees will help to keep these branches calm providing they aren’t shortened too aggressively. A rule we have used successfully in the past is only shorten back to two-year-old wood on the tip of the branch.
As branches age and, providing they are in plenty of sunlight (another key to premium fruit production), bud numbers can quickly accumulate over the years. Eventually the time comes to attend to more detailed pruning and thinning out of buds. This allows better spaced fruit that colours more easily and better target premium market fruit size.
In closer spaced tall spindle blocks that are common in Australia now (2,500 plus trees/ha), the lessons learnt from these newer more uniform systems can easily be applied. Two key changes need to be focused on, branch spacing (as shown by 2D systems that have branches laid down onto wires) and targeting bud numbers. Bud number targets can be set per metre per length of branch, per branch cross sectional area and per tree. Come up with a system that works for you.
Simple, repeatable pruning rules
Correct crop loading is one thing, distribution of the crop evenly through the tree canopy is another. Pruning to the correct targeted bud numbers spaced evenly along the branch will pay dividends as less hand thinning will be required. Less winter pruning means there must be more emphasis on early hand thinning (Nov/Dec).
- Determine the correct number of branches, branch type and density per tree.
- Manage the correct quality and quantity of fruiting buds.
Manage within block and tree to tree variability to help minimise the quality issues that are associated with over cropping.
The following shows examples of pruning rules that might be appropriate for your orchard. However please tailor the rules to suit your trees!
Weak tree < 70 % canopy filled
- 5-7 branches per metre
- Keep stronger branches
- Single the ends of branches
- Remove 12 o’clock pointing shoots
- Remove 6 o’clock pointing shoots
- String up branches pointing more than 45° below horizontal
- Single top (apical dominant)
Strong vigourous tree >110% canopy filled
- 6-8 branches per metre
- Remove biggest, strongest branches that are longer than 1.6m
- Keep moderate vigour branches
- Remove 12 o’clock pointing shoots
- Remove 6 o’clock pointing shoots
- String down branches below horizontal
- Keep as many spurs on trunk as possible
- Consider pruning out 2 more branches in the summer
Calculating the cost of pruning
Pruning is an investment that will pay dividends when executed correctly. The Orchard Business Analysis 2015 shows the average grower will generate $4.73 of Cash Operating Surplus (COS) for every $1.00 spent on pruning, however the upper quartile grower will generate $14.70 of COS for every $1.00 spent on pruning. The top growers focus on the quality of pruning and not the cost because of the compounding effects through the season. While pruning is not the only aspect resulting in a higher COS, it does have a significant influence on other management tasks throughout the season including chemical and hand thinning; pest and disease management; and picking and pack-outs. A well pruned tree has a positive flow-on effect on other tasks and results in a cumulative gain. This is why the upper quartile is gaining an additional $10 of COS for every $1.00 spent on pruning compared to the average grower.
Efficiency gains where less equals more
So does this mean the top growers are spending more on pruning? Not necessarily. Again it’s the quality of the job that’s key. In 2015 the average grower spent $2,295/canopy hectare while the upper quartile grower on average spent $2,025 per producing hectare on pruning, $570/ha less. The statement ‘less is more’ is no truer than with pruning providing the execution of the SNAP (simple, narrow, accessible, productive) pruning rules have been applied. Having clear objectives is paramount and then maintaining robust supervision to achieve the desired outcome. The top growers consistently execute their pruning objectives and in doing so produce trees with a more pick-able crop.
One of the biggest problems that growers face is the inconsistency between pruners and even the same pruner on different days. Pruning lays the foundation down for the crop. If you start with inconsistency at pruning time, you will never be able to produce the perfect consistent crop. Supervising your staff is critical to try and gain consistency across the entire block. Branch counts and bud counts are a way of quantifying the amount of wood and buds left. Do not just rely on your eye as sometimes it can be deceiving.
Pick-ability = increased pack-outs
The 2015 OBA survey showed that the upper quartile group of growers are producing 9.7 per cent more Class 1 fruit but spending 28 per cent less on pruning to achieve this. This effect multiples and results in a pruning efficiency gain of 40.6 per cent with the upper quartile grower spending $58.43/tonne of Class 1 fruit verses the average grower spending $82.16/tonne of Class 1 fruit.
Pruning costs can quickly blow-out, so it’s important to set a budget and then review regularly. An easy way of is to determine the time taken to prune a tree. You can then monitor this daily. Each block will have different budget depending on variety, level of detailed work required, and age/size of tree.
Pruning and orchard systems
Efficiency in pruning is one step in maximising yield and quality. The goal still needs to be maximising marketable yield and cost efficiencies. Consistency drives efficiency and simple orchard systems that are repeatable drive consistency.
SNAP (simple, narrow, accessible, productive) canopies
The adoption of simple pruning rules is made easier with SNAP canopies. Setting rules based on small segments of the canopy allows bud counting be applied with increased accuracy and allows for more easily monitoring by segment, branch and tree. Snap canopies are essential for maximising pruning efficiency. They have also been shown to achieve top yield and fruit quality.
A number of studies have shown the use of platforms reduce pruning time by up to 40-50 per cent by eliminating the positioning and climbing of ladders. This is an impressive efficiency gain with many growers struggling to realise it and then leaving platforms parked up unused. When growers are asked why they are not getting gains in labour efficiency or just gave up on platforms the main reason is tree architecture or orchard system. If we want to achieve significant gains with the use of platforms SNAP canopies are an integral part of the solution. Plan, modify and plant SNAP canopies and the efficiencies will come.
The first you hear of or see mechanical pruning you think ‘no way, it’s too rough, I’ll get fruit damage etc’. Studies have shown labour reductions of 30-50 per cent with slightly lower yields compared to the tall spindle canopy and some improvements in fruit quality. Mechanical pruning gives a new tool in vigour management with the ability to improve light management by maintaining a narrow canopy.
Pruning is a key component to the setting up a profitable orchard. Pruning has a direct flow-on effect through the season where the effects compound and, when executed correctly, results in improved labour/cost efficiencies and pack-outs. Setting, clear and repeatable pruning rules which can be easily monitored is key. A focus on quality is crucial. Newer formal production systems more easily allow for SNAP canopies to be implemented. They also allow for new labour saving technologies to be explored such as mechanical pruning and pruning platforms. Growing for the market is paramount to maximising orchard profitability, knowing the optimum fruit size, and quality parameters the consumer’s demands and then developing and implementing simple, repeatable pruning system/rules to achieve this.