Webinar and considerations regarding late winter freeze and early spring frost risks

I hope it’s not another nail biter of a season, but this ‘winter’ has many of us concerned about early bud break and spring frost risk on vines, again, for many. I want to highlight this webinar offered on 9:00-12:00 AM Thursday, March 14 by Michigan State University Extension Grape program that should be of interest to many. It is free to attend but you must preregister. https://www.canr.msu.edu/events/prepare-for-potential-late-winter-freeze-and-early-spring-frost-risks-in-michigan-vineyards?utm_source=cc&utm_medium=email&utm_campaign=extensiondigests. Find the registration link at the bottom.

As far as any wisdom I have to offer, I am afraid it’s not a lot as it comes to magic fixes as we enter what could be an early bud break. I have had some growers ask me about spray-on frost/freeze inhibitors like RedOx or Agro-K KDL and I just don’t have good independent, consistent, science-based recommendations for their use. That said, if we are seeing frost / freeze conditions that could affect sensitive budded out or deacclimated vines, a couple hundred dollars may be cheap insurance for a product that may not work. At this point, vines should still be hardy down below 0°F based on the Cornell Climate Smart Farming model, so we still have some time before we get too concerned. Note- since many may run over to that model, please keep in mind that models can be erroneously inaccurate based on input parameters. I do not trust the rapid deacclimation that the model shows in thew next week, as I cannot replicate it in any past weather scenarios. I think the model is showing a couple of warmer days coming up and setting a trend based on them, but that is not what the long-range forecast says. Either way, get your pruning done.

On the note of pruning, one practice that we know can delay bud break is to long prune. This works if you are spur pruning, where a longer spur of 4-6 extra buds is left which delays the bud break of basal buds on the spur. It’s likely too late to long prune anything you pruned in winter, and if you do long prune, you will still need to trim those spurs down to 1-2 buds at shoot thinning time.

Good luck out there, and let’s hope the spring comes in like a nice, gentle lamb.


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