In organic winegrowing, three factors are taken into account when renewing treatments:
-
Heavy rainfall: over 20-25 mm, the product applied is strongly leached, so it is necessary to renew the treatment. It is advisable to re-treat if a contaminating rain (mildew) is announced.
-
After vine development, the new organs (leaves/clusters) must be protected
-
After residual effects by products applied. Copper and sulphur usually have a residual duration of about 10 days. Even in the absence of heavy rain and with moderate plant growth, the sprayed product can lose its effectiveness (contact with the sun, wind, dew etc.).