Following vintage the following tips about post-harvest care may ensure vines store adequate carbohydrates for the next year’s growth and production.
Irrigation post-harvest is worthwhile and useful for retaining the leaves on the vines for as long as possible after harvest, which allows generation of carbohydrates for storage in wood over winter.
Irrigation should be balanced, as excess water may encourage new growth, which will use valuable carbohydrates and may encourage late season disease outbreaks Ensure adequate root zone moisture levels are maintained throughout autumn and vine dormancy as vines continue to require water, even after leaf fall.
Application of leaching irrigations to control salt build-up is preferable at the end of winter after winter rains – usually in late July to August. Leaching irrigations immediately post-harvest are usually less efficient, and valuable nutrients may leach out of the root zone.
Selection of fertiliser: With soil temperatures dropping growers may consider using ammonium or nitrate forms of nitrogen post-harvest, as these forms of N are more available than urea under these conditions. Care should be taken with the timing of adding nitrate, as it can be easily leached by rains soon after application.
Foliar nutrient sprays: While some growers choose to apply nutrients post-harvest, many consider the likelihood of nutrient uptake at this stage of the season marginal, as sudden leaf drop means the effort is wasted.
Fungicides: With the exception of late season appearance of mildews, sprays at this time usually offer questionable benefits.
Gypsum: Incorporation of gypsum relies almost exclusively on winter rainfall, and is often applied at this time. In drip irrigated vineyards gypsum application is most often concentrated in a band over the root zone, rather than across the entire row.