reviewed by: Charlie Starr IV (Pest Control Advisor and Grower, Lodi CA), Dr. Akif Eskalen (UCCE Plant Pathologist), and Dr. Maher Al Rwahnih (UC Davis Virologist).
Across California, winegrape farmers are observing – much to their dismay – patches of grapevines mysteriously collapsing. Since around 2010, farmers, pest control experts, extension workers, and scientists in Lodi have done a lot of research on these dying vines. Beginning in 2018, the Lodi Winegrape Commission began to plan this project through case study interviews and regular vineyard testing. Thanks to the work of a group of scientists and growers, we now know that viruses are probably to blame for what we’re calling “sudden vine collapse.” We can also suggest some ways to handle the problem.
Seeing bare, brittle vines in your backyard vineyard can be disheartening. It’s normal to wonder – is my grape vine dead or just dormant? Identifying whether grapevines are truly dead or simply resting requires some detective work. With the right care, you can often revive seemingly dead vines.
In this article, we’ll explore how to tell if grapevines are dead or dormant, common causes of dieback, and tips to rejuvenate vines and get your grapes thriving again.
Dormancy vs. Death
Grapevines are deciduous, meaning they drop their leaves in fall and go dormant through winter. It’s normal for vines to appear lifeless during dormancy. Don’t assume vines are dead without investigating further.
Here are signs vines are dormant, not dead:
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Bark is intact, not brittle or peeling
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Buds are plump, not shriveled
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Scratching reveals green underneath bark
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Roots are firm when dug up
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Support structure is intact
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No signs of disease or dead leaves around base
As long as the vines and roots remain healthy, grapevines will leaf out once spring arrives again. Prune back dead wood and give them time.
Common Causes of Dieback
If grapevines do turn out to be dead, there are a few common culprits to blame. Identifying the cause will guide the rehabilitation process.
Winter injury: Extreme cold can damage buds and injure vascular tissues. Protect vines from harsh weather.
Poor drainage: Excess moisture around roots causes rot and fungal issues. Improve drainage and reduce irrigation.
Pests: Borer insects and diseases like black rot can kill vines if not controlled. Inspect and treat diseased wood.
Neglect: Lack of pruning, water, nutrients, and pest management stresses vines over time. Restore proper care.
Freeze damage: A spring frost after premature bud break will kill new growth. Delay pruning until after danger of frost passes.
Reviving Neglected Vines
Grapevines are remarkably resilient plants. In many cases, recovery is possible through corrective pruning and care. Here are tips for reviving neglected vines:
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Assess the roots. Remove dead vines. Healthy roots mean the plant can be rehabilitated.
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Renew the trellis. Repair or replace broken supports to train new growth.
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Prune out all dead wood. Cut back to healthy white pith. Sterilize tools between cuts.
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Apply fertilizer. Boost nutrients in early spring using compost or 10-10-10 grape fertilizer.
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Improve drainage. Install French drains or plant on berms to reduce wetness.
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Check for pests. Treat borers and disease infected areas. Disinfect tools after pruning diseased vines.
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Protect new growth. Cover vines if late frost threatens so new shoots don’t dieback.
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Train vines. Guide new stems along supports and remove suckers as needed.
With attentive care focused on disease prevention, moisture management, and proper pruning, vines will be fruitful again within 1-2 growing seasons in most cases.
When to Give Up Hope
Despite your best efforts, some grapevines are too far gone to save. If vines exhibit the following, it’s time to remove and replace them:
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Dead, brittle roots that snap when bent
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No healthy white wood under bark
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Shriveled, darkened buds rather than plump buds
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Severe borer damage and tunnels throughout
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Widespread black, shriveled vine canes
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Intense vine defoliation for multiple seasons
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Prevalent grapevine disease like black rot, Pierce’s disease, crown gall, etc.
The healthiest option is to pull truly dead vines, roots and all. Start over with disease-resistant varieties suitable for your growing conditions.
Prevention is the Best Medicine
While reviving neglected vines is possible, prevention is always preferable. Here are proactive care tips:
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Water 1-2 inches per week from bloom through harvest
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Prune annually to remove dead wood and shape vines
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Apply fertilizer or compost in early spring
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Monitor for pests and treat quickly if spotted
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Clean up fallen leaves and fruits around vines
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Cover vines prior to severe freezes if possible
A little attentive care goes a long way for happy, thriving grapevines!
Don’t give up on lackluster vines just yet. Evaluate vines carefully to determine if they are dead or dormant. With time and TLC, you can enjoy homegrown grapes from revived vines again.
Frequently Asked Questions
How can I tell if my grape vine is dead or dormant?
Signs a grape vine is dormant, not dead: intact bark, plump buds, green cambium when scratched, firm roots and support structure.
What causes grape vines to die back?
Common reasons for dieback include winter cold, excess moisture, pests, neglect, freeze damage, and disease. Identify and correct the cause.
What is the best way to revive an old grape vine?
Renew the trellis, prune out all dead wood, improve drainage, fertilize, treat any pests/disease, protect new growth, and train vines along supports.
When should you give up on a grape vine?
If vines have brittle, dead roots, no healthy wood, shriveled buds, severe borer damage, defoliation, or incurable diseases like Pierce’s.
How can I prevent problems with my grape vines?
Provide consistent water, annual pruning, spring fertilizer, pest monitoring, cleanup of fallen debris, and frost protection for healthy, vigorous vines.