Fruit set is the process in which flowers become fruit. The seed develops and the surrounding tissue grows to form a berry. Yes, as strange as it may seem, the avocado fruit is botanically classified as a berry.
Fruit set is a stressful time for avocado trees due to the high demand and competition for resources between the mature fruit that is being harvested, the fruit that is being set for next year’s harvest and the new shoots that will produce next year’s flowers – three concurrent growth cycles.
The challenge is to balance the resource needs of all three growth cycles in order to ensure optimal tree health and performance as well as optimal fruit quality and yield.
It is normal for a large portion of flowers and fruitlets to fail and drop, even under optimum conditions, but good orchard management can ensure improved fruit set.
Improving avocado fruitset
• Practice balanced soil and leaf nutrition. The supply of nutrients from the roots can be insufficient to satisfy the high nutrient demand during flowering and fruit set. Supplemental fertiliser nutrients applied to the foliage can help to meet this demand.
• Pruning management is important for maintaining a balance between vegetative growth and production as well as ensuring adequate light into the canopy for successful flowering and fruit set.
• Seaweed products are a common source of plant hormones important for stimulating flowering and improving fruit set.
• Ensure healthy canopies. Leaves are responsible for providing important resources through photosynthesis.
• Healthy roots are important in order to produce cytokinins, support the tree by efficient nutrient uptake and supply adequate water to meet the increase in transpiration during this period.
• If you are fortunate enough to have irrigation, now is the time that you will reap the rewards. Any water deficit stress during fruit set will result in elevated fruit drop.
Fruit drop can continue well into February, and ensuring we do everything we can to minimise unnecessary fruit drop will ensure we line our pockets rather than the orchard floor.