Is this all roundup damage? I hope I didn't really screw things up.

[TimTheWiner]

Ok, thanks for all the great replies. I will have to make sure to cut back late winter or early spring, I'll have to stop with the Sevin for a while and see if I can apply something for the mildew/fungus and water ASAP

 

[Tess]

looking at the underside of the leaves it does looks like Mildew to me also.
Its probably because water set in the tubes on the plant longer. I dont understand anyone using round up on anything now days. Why use a harsh chemical that cost you a fortune when straight white vinegar does the same thing on a HOT SUNNY DAY? Im just sayin!!
ok..ok, Im done preaching the straight white vinegar and small tiller thing. Good Luck with the plants!!

 

[GreginND]

Glyphosate is safe and effective if used properly. Vinegar just doesn't work and would be much more expensive to cover an acre of weeds.

 

[Tess]

Glyphosate is safe and effective if used properly. Vinegar just doesn't work and would be much more expensive to cover an acre of weeds.

Well as I said, I don grow grapes but I do use it with great success in my garden. I can not afford round up. I can get a gallon of vinegar at Wally world for a couple bucks but I can see where it might be hard to get as much to cover an acre. It really does work though

 

[HillPeople]

Not roundup damage IMHO Shockwave. We had blue tubes on 100 vines planted in May and things were moving along fine until that 2 weeks of rain and then the heatwave at the end of June and beginning of July. Prime conditions for growing fungus, so we took all the blue tubes off early to let the vines dry out. They slowly recovered with the exception of the Louise which were severely set back.

You won't regret cutting the feeble vines back to 8" or so with 2-3 buds next March. They will take off very nicely and then as Grapeman said you can start a spray routine to keep the fungus and mildew at bay.

We just inoculated the vineyards with 5 million beneficial nematodes (Hb) to try to breakup the Japanese Beetle life cycle a little for next year. Picking 100-200 a day morning and night gets a little old, but I'm avoiding Seven if it's possible.

It wasn't a favorable summer for the vines, but ours have been putting on an amazing amount of new growth for this late in the season.

Good luck.

 

[TimTheWiner]

Ok good to hear. Looking forward to see this project evolve.

 

[Handy Andy]

Are Vines partly or completely immune to Roundup?

Is it OK to spray with roundup after the vines have leaves on them?

 

[SheridanVines]

Are Vines partly or completely immune to Roundup?

Is it OK to spray with roundup after the vines have leaves on them?

They are definitely not immune. The best you can hope for if any hits a leaf is you don’t kill them and they look ugly for a year while they metabolize the glyphosate. Use grow tubes and hill soil around the bottom if you need to use roundup.

there are several brands of glufosinate that will burn leaves but not kill your grapes. Liberty, interline, Rely to name a few.

 

[treesaver]

I use Liberty, and been very pleased with the results.

 

[Handy Andy]

They are definitely not immune. The best you can hope for if any hits a leaf is you don’t kill them and they look ugly for a year while they metabolize the glyphosate. Use grow tubes and hill soil around the bottom if you need to use roundup.

there are several brands of glufosinate that will burn leaves but not kill your grapes. Liberty, interline, Rely to name a few.

Last year I mostly strimmed the weeds, until all the leaves were off my vines then I sprayed with roundup a couple of times and the weeds seemed to be under control. Until the last month or so when they have started coming back. This is I think due to a fool(me) with a hoe removing one or two weeds losing the top soil and allowing more weed seeds to find a way to the surface

Thanks for the clarification ref roundup, I was wondering about using a selective weed spray, but most of my weeds appear to be broad leafed, not unlike a vine. I will go to the fitofarmaceutica shop and see what they have.

I am also considering weed matting, if I cant get a spray.

 

[SheridanVines]

How old are your vines? There are several products you can use to keep weed seed from germinating, but with some of them you can’t get any on new growth. I used Prowl, but chateau (aka valor) would work well too. The thing about weeds is even if you kill them, more will always come with rain. Preemergent chemistry is your best bet to work in tandem with a non selective herbicide like roundup or liberty.

 

[Handy Andy]

I am not 100% sure ref the ages of the vines some are older than others. I am guessing they age from between 5 and 20 years old in my Verdelho vineyard and less maybe 5 years old in my American tinte and Alverinho vineyards. I didnt ask the previous owner how old they were, when I bought the place. I didnt know to ask the question.

It has rained a lot more and is cooler than usual, due to global warming perhaps, which may be assisting my weeds.
I wonder if pre-emergence sprays would be effective with the amount of rain we have had this spring?

I am on top of the powdery and downy mildew at the moment, but noticed some of my neighbours vines are looking distinctly sick, not unlike mine were last year.

 

[SheridanVines]

Preemergent herbicides actually require a certain amount of rain, normally 1/4”-1/2”, to activate in the soil. Large rain events will cause its effectiveness to decrease sooner, but you can reapply later in season to get you through the rest of the year.