Post-harvest Nutrition: The Golden Opportunity for Next Year’s Crop Starts Now!

During post-harvest, nutrients are taken into plants from leaves prior to leaf drop.

Therefore post-harvest is a critical time to apply soil based and foliar nutrition as vines actively translocate nutrients to the buds, canes, trunk and roots, to store these elements and carbohydrates for the next season. There is also an active period of root growth post-harvest throughout autumn until 2 weeks before dormancy.

Post-harvest is a critical time to apply fertilisers to the soil as the roots are actively growing and therefore have the capacity for uptake and convert to carbohydrate storage.

The greatest loss of yield potential occurs when postharvest applications are missed. This is a golden opportunity that has the single biggest impact on next year’s crop potential.

Our observations from plant Sap Analysis results, show a high number of vineyards start the season in negative nutrition balance because of this missed opportunity.

Post-harvest is also a critical time to correct any deficiencies noted leading up to or during harvest.

Results from Plant Sap Analysis from that period can help manage deficiencies.

This is a good time to have a look at the elements required for optimising flowering and fruit development. It is important to have sufficient levels of these elements in the buds prior to budbreak.

Not only is nutrition important but irrigation management is also critical. Dry soils after harvest inhibit the second flush of root growth and cause early leaf drop, limiting the build-up of carbohydrates and nutritional reserves in the vine.

Grapevines rely entirely on stored nutrient from budburst until the 5-6 leaf shoot stage.

Post-harvest is also a perfect time to start soil testing and compare the results with the previous year’s Sap Analysis results. It will allow for sufficient time to apply fertiliser before the mad rush in late winter and early spring.

Soil or foliar application - or both?

Fertigation can be used directly to the wetted area and active root system of the vines. Depending on the vine canopy’s health post-harvest, foliar applications can be beneficial. Certain elements are best applied as a foliar due to the reduced availability of these elements through the soils.

Summary

Post-harvest Nutrition is often overlooked but it is a golden opportunity to ensure the plant has access to the correct nutrition to have the biggest impact on next year’s yield. Understanding application of the correct nutrients postharvest and managing with plant sap analysis and soil test results, is critical to improve yield, fruit quality and vine health. A balance of soil and foliar applications of nutrients is possibly the best approach at the end of the season when making product selections.

Your next season’s nutrition management program starts now!

Discuss your post-harvest nutrition requirements with your Farmlands Technical Advisor. They can advise on the availability of options and solutions.

Mart Verstappen Technical Leader - Viticulture