with Erica Faber
Looking ahead in the avocado calendar, there is flower induction, flower initiation and bud development. Starch accumulation is also occurring, preparing the tree for the upcoming demands of flowering and fruit set. The main orchard priorities for the next quarter are as follows.
Soil and leaf sampling
Soil and leaf sampling are taken so fertiliser programmes can be tailored to ensure optimum nutrient levels and tree health. Nutrient deficiencies and poor reserves will translate into declining tree health and poor fruit set.
Preparing for spring plantings
Make sure you have taken soil samples, completed your soil corrections and prepared your land for planting well before your planting date draws near.
Phytophthora root rot control
Crop load, nutrient deficiencies, environmental stresses and the demand on reserves for flower development can cause a tree to be more susceptible to diseases and could be the trigger for decline during the wet, winter months when roots battle against the high pressure of Phytophthora. Control should not only be chemical but also cultural, which will result in healthier roots more resistant to PRR and a soil environment where it is suppressed. Cultural methods include application of organic matter and soil supplements to stimulate microbial populations and activity.
Autumn signals the start of pruning. Besides controlling tree height and improving light penetration into the canopy, pruning also ensures more consistent return crop by balancing the productive and vegetative canopy. Open canopies also ensure better spray penetration and coverage and also less favourable conditions for fungal pathogens.
Fungal rot management
Control is most effective by using an integrated approach of cultural, chemical/biological and nutritional management tools.
Disease results from interactions between a pathogen, a susceptible host and suitable environmental conditions. Changes to any three components accelerate or suppress fungal diseases. The most effective control method of fungal disease is prevention – and disease management therefore relies on cultural, biological, and chemical methods. Pruning, orchard sanitation, ensuring optimum tree health, following proper harvest procedures as well as copper sprays are all part of managing the disease cycle.