It’s been a difficult year and most can’t wait for it to pass… but just before it does, spare a thought for the vines that have to stump up again next year to help turn things around! Post-harvest nutrient application is critical to support early spring growth in the following season.
- Consider both nitrogen and phosphorous applications post-harvest.
- Irrigation must be managed in conjunction with post-harvest fertiliser applications to avoid forcing late shoot growth that will negatively impact vine growth at bud burst.
- The sooner nutrient is applied following harvest the greater the uptake and subsequent benefit to vines in the following season. Nutrient applications made shortly prior to leaf fall will be of marginal value.
- Both nitrogen and phosphorous should be considered in post-harvest fertiliser applications.
- Generally 30% of the season’s nitrogen should be applied post-harvest.
- If applying fertiliser via fertigation regular moderate applications to leaf fall.
- As a general guide:
– Reds can require – 20kg /ha urea and 20kg/ha MAP; which equates to 12 units N/ha and 4 units P/ha.
– Whites can require 30kg/ha Urea and 25kg/ha MAP; which equates to 18 units N/ha and 5 units P/ha.
– 1 T grapes removes 2kg nitrogen, 350gm phosphorous, and 2kg potassium.
Thanks to Nicole Pitman of CCW for these timely tips.