Yellow Tree

Pre-harvest Thinning

November 30, 2020

The pre-harvest thinning helps with packhouse efficiencies, but does it also make financial sense for the grower?

Packhouses only charge reject rates if that percentage is greater than 10%. As it penalises all trays - not just the ones above the threshold, it soon becomes a very costly exercise.

What to consider and how to make the decision?

To decide whether it is worthwhile, you need to determine the percentage of reject fruit and the difference between the thinning cost and the cost of not thinning (i.e. post-harvest packing reject charges).It’s important to understand that pre-harvest thinning will also save money in harvest and transport costs.

Which are the most likely rejects to be targeted in the pre-harvest thinning?

Rejects missed in previous rounds, wind rub and sooty mould (had passion vine hopper).

What are the practical steps to help with decision making?

1. Walk each block to get a good understanding of reject levels

2. Count 1% of representative bays to get a confirmation on reject percentage

3. Using an online calculator provided by Zespri or packhouses, run a few scenarios to make the best possible financial decision

4. Monitor cost of thinning to stay within the planned budget

As part of the recent presentation by EastPack Entity Trust, a sample was provided where the reject level pre-thin sits at 18%. It outlines the most likely financial outcome if the grower decided to thin that number of rejects down to 10%.