Now that the buds on the orchard have pushed out shoots and leaves, we get to project our crop loads and targets (or canopy cover in establishment).
We utilise the flower buds on our shoots as projections for how many fruit the plant has naturally given, and how many we want to remove to get our estimated crop. We often don’t keep the side flowers as these are usually smaller fruit, but if we have low flower numbers, we may choose to keep them for fruit numbers.
The importance of flower thinning at this time of year is crucial because it allows the plant to focus all its resources on flowers and fruit that we want to keep. If we don’t thin out the flowers we don’t want, we will be left with lots of small fruit because the plant doesn’t have enough energy and nutrients to provide for all flowers. It will also have a major impact on the quality of the fruit due to its carbohydrate and dry matter content which are crucial at the harvest season as these factors influence maturity.
Flower bud thinning will ensure our canopy has a uniform and consistent yield which allows for even chemical distribution among fruit and a uniform pollination season. Another major factor influenced by flower thinning, is the reduction on plant stress which can increase the likelihood and severity of pests and diseases. Stressing out a plant too much can result in unsellable fruit, and 5 years of fruit loss if we have dead.
Strategies for flower bud thinning are often structured per cane or per bay. A manager will work backwards from a crop load target they would like to achieve, and then work down to a singular fruits per shoot strategy. Managers then have teams remove excess flower buds above these numbers to ensure we are at our expected target.
In the Southern Hemisphere, we are in a time of the season where irrigation, frost protection, and PSA protection is priority. PSA is most common when temperatures are favourable (often lower), and moisture content is high.