By Barb Wloka
Although it may seem contrary to the end goal, thinning fruit is very, very important for both fruit quality and fruit size. There are a few ‘rules’ about fruit thinning, but as with most things farm related, each product each year must be considered carefully.
Take, for instance, peaches. On a normal year, thinning is done so that fruit is separated by 15 to 20 centimetres (6 to 8 inches). If the crop looks large and the weather predictions are good (no frost or cold weather on the horizon), then thinning for peaches may start with blossom thinning. But this is a gamble and a decision that is made with a lot of consideration first.
For peaches, there are a few spots where fruit should never be left. Fruit that sits in branch crotches are removed simply because they will be deformed and are more likely to be damaged during harvest. And fruit at the tip of a branch is removed simply because of its weight. A branch will support a peach better halfway down than at the very end. And a peach at the end of a branch is much more likely to be damaged by machinery and ladders moving through the orchard. In a year with a full crop, thinning is performed up to five times to ensure the crop is spaced well. It is amazing what gets missed each go through!
For apples, the very blossom structure is different. Rather than a lot of individual blossoms, an apple will bloom with a central blossom first (called the King bloom) and then with four or five side blooms, all from one bud. If all is ideal (great weather, good pollination, etc.) that central bloom will set first and therefore provide the largest fruit. Thinning is then done to remove the side blooms/fruitlets. This will allow for all the tree’s energy to go into growing that king bloom and will let light and air flow around the young apple for optimum growing conditions. Spacing of the apples will then depend on the variety and vigour of the tree.
Some fruit, such as cherries, do not benefit from fruit thinning. The size of the final fruit for cherries is determined by the prior pruning done to ensure the tree will have a manageable crop size. Once the fruit is pollinated and set, no amount of removal of fruit will impact the size of the cherries developing.
And then there are plums and apricots and pears… each has its own idiosyncrasies that must be considered to maximize crop and fruit size. And this is why farming is such fun!
Barb Wloka is owner/operator of Wloka Farms Fruit Stand in Creston, B.C. She and her husband, Frank, have farmed for over 40 years and, during that time, have learned a lot through trial and error. To grow their knowledge base, both continually research and collaborate with others. Finally, they also pick up tidbits of information from staff and customers. Learning to farm is a life-long educational experience!