Red leaves...

[Rocktop]

Hi all, wondering if I can get some advice.
Last year I established 150 vines, La Crescent, Lemberger and Gamay Noir. All was going great until late summer/early fall when I noticed a lot of leaf edge burning and then eventually leaf yellowing and dying. One end of my vineyard looked worse than the other. My two main suspects were salt buildup from my well water or lack of proper fertilizations - Mg deficiency (I am on very sandy, poor soil). Over the winter many of the plants that looked poor going into the winter did not survive even though it wasn't a particularly bad winter. I had probably 50% kill....

This spring I planted another 150 vines (PN, PGris, Chard, Rielsing, Gewurtz). Also this spring I got a soil sample done and a custom fertilizer blend done. I would say in general, all remaining and newly planted vines look great. However...

In the last couple of days I have noticed a couple of plants going to red leaves. It is starting at the bottom of the plant and working up. Given last fall's issues I am hyper sensitive. The pic I have attached shows the progression on leaves from one pinot noir plan. Green with some little red dots, then generally full red leave then full yellowing.
Nighttime lows have been normal at about 8 degrees C or 46 degrees F. So I don't think it is fall color change yet.

Do I have a major issue that is going to spread?

Thank you
RT

 

[balatonwine]

Several options (not fully inclusive, only the main ones I would consider first).

• Normal senescence (i.e. late summer fall leaf color). Some varieties turn red sooner than others.
• Early fungal infection now causing early senescence (the middle leaf has a spot that might be downy mildew).
• Weather and climate (these grapes are not ideal for your area so are suffering and will drop leaves early).
• Soils --- ranging from water availability to nutrient quality meaning the plants can not sustain leaves into fall.
• Could be micro nutrients, but that would more likely show up earlier in the growing season.
• Mites (but that usually occurs from top down).

Hope this helps.

 

[Rocktop]

Thank you Balaton,
I think it may just be natural fall colouring just seemed early and as said I’m super sensitive given last year’s loss. I did note the maples are starting to turn so I’m feeling better…

I will keep a close eye on it and reach out to you if it changes.

‘thanks

RT