Be Aware of Phytochemical Burn

 Hello Dear Growers, and Happy long Weekend!

As we rush through flowering (again, seems to be happening overnight) due to the recent heatwave, we have to be mindful when spraying.

We have had several calls this week - with growers worried about what looked like disease spreading through their vineyards. 

I advise anyone who is unsure to send photos, texts about what they are seeing. Indeed, some chemical burn can look like Anthracnose and even Black Rot. 

Here are some examples of what we have been seeing the last couple of weeks: 

  

These are examples of young vines and established ones. What we see here are various burn marks, but also distorted and "waxy" looking, young leaves with chlorosis. 

The symptoms may look like a myriad of things-especially when a disease is just getting established, so it important to get a second opinion if you are unsure of the cause.  

Why does this happen? Is it just because it is hot?

Chemical burn can happen for several reasons:

-Cultivar Sensitivity. Some Hybrids are more sensitive to sulphur than others. Meanwhile, vinifera are not sensitive to sulphur.

-Spraying mere water in hot weather can cause leaf burn.

-  Spraying a mix of products during warm weather.

- Spraying a mix of products in addition to nutrients. (Temperature may be irrelevant).

-Spraying products that are not compatible with each other. 

Sometimes, it is not one product that is causing the problem, but the totality of  products sprayed together or in close succession to each other. 

I advise you to follow the labels closely. 

This is especially important when spraying nutrients in close succession to the phyto products. The labels may not state if the products are compatible for spraying simultaneously. If you are unsure, I advise you to text, email or call me prior to spraying. 

PHENOLOGY

Osceola Muscat:  Past flowering and into fruit set. 

New York Muscat: No flowering

L'Acadie: flowering starting. About 2%.

Petit Pearl: No flowering

Marquette: 80% Through flowering.

Baco Noir: 90% Through flowering.

Lucy K: 90% Through flowering.

Triomphe de Alsace: 85% through fruit set.

Frontenac Blanc and Gris: 90% through flowering and starting fruit set.

Chardonnay, Pinot Noir and other vinifera: No flowering.

If you have any pictures, anything that is worrying you in your vines, do contact me. I hope you had a lovely weekend and Happy Canada Day!

Cheers!

Katarina

 

Katarina Vucic P.Ag; MSc; DipWSET

Viticulture Specialist
Perennia Food and Agriculture
Email kvucic@perennia.ca
Office 902-678-7722

Cell 902-599-1390