Leaking Grape Vines After Pruning – It’s Called Bleeding!

Knowing exactly when it’s the right time to prune your grape vines is pretty important.

bleeding grape vine
bleeding grape vine

If you prune at the wrong time of year, you may notice a sticky, oozy sap coming out of the vines. It’s not a disease, but instead, a reaction to the pruning.

The condition is called “bleeding”. Supposedly it’s best to just let the plant heal on its own (as opposed to painting something on it to make it stop leaking). In extreme cases the plant can die, or can become less vigorous.

Experts recommend that you do your pruning in Fall or early Winter, when all of the leaves have fallen from the plant.

During dormancy the sap in the vines is at a low level, and bleeding is less likely to occur.

When it starts to get close to Spring (even mid to late winter), the sap begins to rise again, delivering water and sugar to the growing leaf buds.

If you prune during this time, you are disrupting the flow of the sap and the result is dripping vines. Like mine.

Fortunately, grapevine bleeding is fairly easy to prevent. Here’s what you need to know about why grapevines leak – and how you can stop it.

Is Grapevine Bleeding Bad?

While grapevine bleeding may sound like a bad thing, it is actually a natural and necessary part of the plant’s life cycle. The loss of solution helps to flush out any accumulated salts and minerals that could potentially damage the plant.

Grapevines also use this opportunity to regulate their sugar levels before the start of the growing season.

While grapevine bleeding is generally not a cause for concern, there are some circumstances where it can become a problem.

For example, if the weather is particularly cold, the loss of solution can deplete the grapevine’s reserves of sugars and minerals, which are essential for protecting the plant from frost damage.

In addition, grapevines that are grafted in the spring are particularly vulnerable to bleeding damage. Therefore, it is important to be aware of the potential risks associated with grapevine bleeding and take steps to protect your plants if necessary.

Why is My Grapevine Leaking Water/Bleeding?

Xylem is the woody support tissue that carries water and minerals from the root systems through the stem and into the leaves. As soil temps reach 45-48 degrees F. (7-8 C.), root growth surges, leading to a jump in xylem activity. This increase in activity can cause the grapevine to bleed or leak water.

Bleeding happens when xylem has been damaged and sap flows from the cut.

Maintaining proper moisture levels in the soil can help to prevent bleeding.

Watering deeply and regularly will help keep roots healthy and prevent them from becoming stressed. In addition, pruning grapevines in late winter or early spring before new growth begins can also help to reduce the risk of bleeding.

If you notice your grapevine leaking water, check the roots and prune any dead or damaged canes.

Pruning Before Budbreak

Pruning grapes in early spring before bud break can sometimes lead to bleeding. This is because when the vine is pruned, it releases hormones (cytokinin and gibberellin), amino acids, sugars, and nutrients into the exudates. These substances help to regulate budbreak and early growth of the vine.

However, if the vine is pruned too heavily, it can lead to excessive bleeding.

This can occur at any time the year when the plants are actively growing, but is more likely to happen if the soil temperature is between 45 and 48°F. This is because at this temperature, root growth begins and there is a surge in xylem activity.

Environmental Conditions

In some cases, it is not pruning that causes the bleeding. It is just an effect of environmental conditions, the rising temperatures and the level of water reserves.

In short, bleeding simply shows that the plant has come back to life.

The process usually lasts seven to ten days, after which the vine will start to produce new leaves and shoots. Bleeding can be worrisome for grape growers, as it can sometimes lead to loss of yield. However, it is a natural process that helps the vine to adapt to changing conditions and should not be cause for concern.

bleeding grape vine
another bleeding grape vine

Preventing and Stopping Grape Vines from Bleeding

Bleeding is when the sap from the vine seeps out and flows down the length of the vine. While this isn’t harmful to the grape vine, it can be detrimental to grafts.

If you’re doing them, excessive bleeding can make it hard for the rootstock to come into contact with the cambium layer (the growing layer of the plant just under the bark). As a result, your grapevine might not produce as much fruit as you’d like.

Fortunately, there are a few things you can do to prevent or stop grape vines from bleeding.

Here’s how to limit it.

Make Incisisions Only at the Base of the Vine When Grafting

When grafting grape vines, it is important to make incisions only at the base of the vine. This will prevent bleeding from the graft site and direct it to the base of the trunk.

By doing this, you will be able to keep your grape vines healthy and prevent them from losing valuable nutrients. In addition, this method of grafting will also help to speed up the healing process.

Prune at the Right Time of Year

Pruning grape vines is a delicate balance. Prune too early in the season and you risk damaging the vine. Prune too late and you won’t have enough time for the vine to recover before winter sets in.

The best time to prune is actually just after the grapes have been harvested. This gives the vine time to heal before winter, and also ensures that any new growth will have time to mature before the next growing season.

Follow Recommended Pruning Techniques

While grape vines can be pruned at any time of year, it’s important to follow recommended pruning techniques to prevent the vines from bleeding. When pruning, always cut at an angle and avoid cutting too close to the main stem. This will help promote new growth and prevent the vines from bleeding.

Wait Two Weeks

If you notice your grapevine bleeding, the first thing to do is to wait and see if it stops on its own. In most cases, grapevine bleeding is a natural process that occurs as the vine shedding its leaves and going into dormancy for the winter.

The vine is essentially losing excess moisture and nutrients that it doesn’t need during this time. Bleeding usually lasts for two weeks or less and doesn’t require any treatment.

Final Thoughts

Grapevines are easy to grow and care for, but they can be finicky in some regards.

If you’ve noticed your grapevines bleeding, don’t panic. Nine times out of ten, they’ll be just fine. Follow these tips to help make sure they see it through!

14 thoughts on “Leaking Grape Vines After Pruning – It’s Called Bleeding!”

  1. I live in southern California and have one Vine (5ys) I usually let it drop most leaves before I prune. But this year it grew ridiculously out of control so I cut it back to four runs. It’s August but still hitting 117 degrees. It bleeding bad. Is there anything I can do to reduce the hemorrhaging.

  2. Just for the record, 2 days ago I cut the dead wood on an old vine, to tidy it up. The vine was just starting to flower.
    Unfortunately I cut more than one branch with sap in it. 2 branches did not drip, they flowed steadily for at least 4 hours, possibly 12 hours. 48 hours later, 4 branches are still bleeding freely. I can imagine they will kill the vine. The drainage of food must have a dreadful effect on the vine. Even a well established one. I have tried a putty type cover on the cut with no effect.

    • This happened to mine today. I pruned in January. Our temps have been a steady 60° … In SW idaho. Came accross this link. As wellhttp://articles.extension.org/pages/65035/grapevine-bleeding

      • Oh boy I think I hurt my grape tree,I cut it a few day ago and is still dripping water, I learn my lesson, thank you for your advice on this matter.

  3. Hello Kendra, I pruned my grape arbor last week and I really pruned it. about four years ago I went about a foot and a half off the ground and it came back wonderfully. didn’t get grapes of course til the following year. but I did get lots of grapes and it was wonderful. so its been awhile ,and last year I got a good crop but they all turned to rasins and dried up. grrr. so my son who was missing homemade jelly went and picked wild grapes, wonderful jelly ! so determined I’d get grapes this year about four weeks ago my hubby went and trimmed them, hhmm, he didn’t take off as far as I was concerned so last week I did what my brother told me to do, which was to leave two good runners on each and get rid of the rest. my dad use to has so many grape vines. I have six from his original farm. so I didn’t see any bleeding so far that I know of but we shall wait and see. don’t think i’ll get grapes this year though. hubby was not too happy, so we are just gonna see who was right. because he definitely didn’t take hardly any off. the sun would not be able to get through which was the problem………..ciao for now

  4. Aww! I’m so sorry this happened to you. Most deciduous plants and trees require pruning while they are dormant, which is usually when it’s coldest and the after the leaves have all dropped, as you now know :(. APRICOT trees, on the other hand, can’t take the cold and should be pruned during summer.

  5. We just moved into a new house at the beginning of April. It came with a row of grapevines in the backyard. I just noticed the other day that this thick, gelatinous substance was oozing from the pruned parts. Is this the same thing? I hope they will produce for us!

  6. I just noticed this on ours too. Grr. We switched from spur to cane pruning on these because cane pruned vines are supposed to do better in cold climates. So there were some major cuts. I would be so upset if they died! Mine aren’t dripping water though- it’s more congealed… do you suppose it’s the same thing but just because it’s still chilly here?


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