Critical time for supporting 2018-19 fruit set
As our trees start to gear up for flowering, I thought it would be worthwhile to summarize the field day information for those growers who were not able to attend and for those that did attend I have included some additional information, so keep reading.
The following isn’t a recipe card, it is what has worked for me and certainly if you are not getting results then
you have to try something different. when it needs it we first need to understand the tree phenology
so that we can be two steps ahead.
It’s important for growers to understand that every action they make triggers a hormone reaction in the tree - we want growers to know that what they are doing will have the desired outcome.
At this time, there is a seasonal change of lower temperatures and shorter day lengths and flower initiation is being triggered
within the tree.
Hormones trigger the transition from vegetative to floral buds but it is the nutrient levels and balances that drive this reaction and the carbohydrate levels that determine the stamina of this reaction.
This pre-flowering and flowering stage is one of those critical stages that we as growers need to ensure the tree has all the resources it needs, in order to optimize production.
I advise foliar spraying of nutrients to support the tree through this critical period of specific nutrient demand for bud differentiation, fruit set and fruit growth.
Solid fertilizer is a traditional choice but foliar application can overcome soil fertilization limitations such as leaching, runoff, nutrient fixation in the soil, limited root activity due to low winter temperatures or poor root health, antagonism between certain nutrients, pH limitations, soil moisture levels etc.
Ensure correct nitrogen levels. Excessive nitrogen in the tree at this time will swing the balance in favor of vegetative growth, thereby compromising potential flowering and fruit set. • Apply products to boost root health and vigor, and soil
health and fertility. • Foliar sprays of seaweed products will boost cytokinin levels as seaweed extracts are particularly rich in cytokinins which effect fruit set and size. • Apply a foliar spray of boron at the pre-flowering stage
to improve your flower to fruit ratio. • Apply calcium as this works in close synergy with boron for flower development & fruit set. It also increases cell wall strength which not only improves fruit quality but also aids in resistance to anthracnose and post-harvest rots.
Potassium is extremely important during this fruit-fill stage. Insufficient levels of potassium reduce the yield potential and quality of the crop and ultimately our pockets! • Zinc is one of the most important elements in carbohydrate metabolism in plants which in turn determines the stamina of critical reactions at this important reproductive phase and also in improving the flower to fruit ratio. • Bees – The more you have the better your odds. Remember to book your hives now for the start of delivery at about 10% open flower. Aim for 6-12 hives per hectare depending on your tree density, size and age. Erica Faber joined Just Avocados in January 2017 after emigrating from South Africa. She has over 21 years’ experience in the horticulture industry with 16 years as a technical advisor. She has gained recognition in the citrus and avocado industries for innovative contributions improving propagation, production and profits.
Most recently she managed all facets of production on a 175Ha avocado operation in South Africa. Erica was responsible for the yearly 20-40ha expansion of the orchard, market and customer compliance and harvesting to integrate with overseas markets to ensure optimum profitability.
While managing this orchard, Erica carried out a number of avocado research trials on irregular bearing, pest control, pruning techniques, and influencing the onset of bearing in young trees. The application of positive learnings from this research significantly improved the profitability of this business.
In her role with Just Avocados, Erica leads programmes to support our growers nationally to increase their productivity, including providing technical advice, targeted field events and regular and proactive communications with regards to orchard management.