I’m often asked whether copper (and manganese) based pesticides provide any nutritional effects to plant. Does the plant absorb the minerals from those products? Can those bacteriacides and fungicides double as replacements for Rebound Copper or Rebound Manganese?

The short answer is no.

Those disease-control products are specifically formulated to remain on the leaf surface. They have been designed to deliberately avoid absorption by the leaf through the use of adjuvants like spreaders and stickers.

By contrast, nutritional copper and manganese are specifically formulated to get into the leaf as readily as possible.

You must be careful when using tissue analysis or sap analysis on crops that have had copper or manganese pesticides applied. Their minerals will show up in tissue analysis, because the entire leaf, including materials on the surface, is ashed to perform the analysis; and to a lesser extent in sap analysis: when the sap is pressed from the leaf, it runs across the leaf surface and can pick up some of the copper.

Applications of copper and manganese can skew the readings on your test results; you should use this awareness when you interpret them.

 

Copper’s benefits as a nutrient

Copper is a key nutrient at the Bud Initiation, Bloom, and Fruit Fill Critical Points of Influence.

  • Copper is a factor in the immune systems of plants–copper levels are often associated with disease susceptibility
  • Helps control the growth of mold and fungi
  • Contributes to cell wall elasticity
  • Gives greater stem flexibility; can help prevent fruit from snapping off or splitting
  • Reduces risk of fruit cracking
  • Improves pollen quality by preventing premature rupture of pollen sacks
  • Can help varieties that have trouble with pollination
  • Helps produce a high quality crop with higher storability

Don't miss John Kempf's next post. Subscribe.

You'll get each post to your inbox (~1-2x/week).

You may unsubscribe at any time. We value your personal information. Here's our Privacy Policy.

"*" indicates required fields