Dying grapevine?

[Ben1030]

Hi

I seem to have a problem with my grapevine. It's 2 years old, last year it grew really well in the small pot I had it in. I pruned it in the winter and repotted to a larger container. When repotting I accidentally snapped some of the lower roots off that were stuck in the pot. I used John innes 3 mixed with perlite, also added some chicken manure pellets.

The 4 buds started to grow as normal and even looked like it was going to flower for the first time. During the last week of hot weather I noticed the end of the new growth had turned brown. There are also some little green dots, not sure if these are pests or sap. One of the buds and turned fully brown and died. I did water during the hot weather but not too much as there was hardly any leaves on.

Any help or advice would be much appreciated.

Thanks

Ben

[Snadger]

I will be interested in any replies you get as mine has a similar problem. Mine was also a new vine last year which grew well but this year is similar to yours.
I'm going to tip mine out of the pot and see if I have vine weevil at the roots, but apart from that have no idea why its happening.

[Deltawhiskey]

Hi Ben,
What variety are you growing and is it grafted? What size pot are you growing in?
Not sure what the problem could be but snapping off a few roots in winter should not be a problem. As for watering, as long as you pot has good drainage you will not over water. In a pot the roots cannot search for water so in hot dry weather give it plenty. It was said in the past that grapes will not grow north of the Wash but both times and the weather have changed and new vine varieties have come on the market. However in a pot the soil freezing solid could damage the vine. A late frost can kill off new shoots but these are normally replaced with new shoots from dormant buds. The green dots could be bugs like greenfly but a vine should be able to outgrow any damage they can do. A good indication is ants on the vine 'milking' the bugs.
Hope this helps

David

[Ben1030]

Hi David

The vine variety is 'Vanessa', it is grafted. It was described as been one of the best for 'up north'. I think its Canadian in original from memory. The container size is approx 30cm plus, more than double last years which it didn't fill. I did have some vine wevil in a nearby strawberry, I treated everything. I didn't find any when repotting the grape.

We had a warm spring although the vine is mostly in the shade that time of year so bud burst wasn't too early. Can't remember any bad late frosts this year. It's in full sun from May to sept. We do have a commercial vineyard up the road in Holmfirth now, its pretty high up too!

I did accidental knock a bud off the vine a Week or so before it went brown. I didn't see any sap bleeding out though. It looks even worse now! Worried it's going to die and I'm going to have to start over again!

[Scarlet]

A long shot maybe....but are you sure it hasn't been hit by a frost? I'm in the South West and have had several bushes hit in May. I assumed one of my red acers had died but on closer inspection this weekend I could see some new growth starting again...all its early leaves had died off from frost. Also the underside of the leaf that is opened is a similar colur to the buds....I would just give it a feed, ensure you are watering well in the hot spells even if there aren't many leaves.

[Ben1030]

If it was a frost would it regrow shoots after the current ones have died?

Could he roots have gotten too hot in the container?

[Snadger]

My problem with vine was that the drain holes had got blocked in the pot it was in. Poor thing was drowning. I've potted it on so hopefully mine will recover.

Hope yours recovers Ben.

[Ben1030]

I hope thats not the problem with mine as I've watered it loads in the last week. It started during a heatwave so hoping it was too dry and now improves.

[Ben1030]

My problem with vine was that the drain holes had got blocked in the pot it was in. Poor thing was drowning. I've potted it on so hopefully mine will recover.

Hope yours recovers Ben.

Have you got any pictures of yours to compare?

[Snadger]

Have you got any pictures of yours to compare?

I repotted mine and pruned off the bad bits. Time will tell.

[Ben1030]

Update on condition

[Ben1030]

Update*

It's looked dead for the last 2 months and starting to shivel up, I think that's it.

Would a late frost kill it?

[Scarlet]

Yes, I lost several shrubs this year to a late hard frost.

[Deltawhiskey]

Hi Ben,

Most grapevines are extremely tough and it takes a really hard frost to damage them in the dormant period. If yours is indeed a Canadian variety then it should laugh off a UK winter even if the soil in the pot freezes solid. Spring frost can kill the new buds but others will grow later. The pot you have it in does sound a bit small. Remember that a vine in the right ground can put roots down to 4 metres or more. It may be as you suspect be getting too hot despite regular watering. So you might try insulating the pot or even putting a piece of wood on the sun side of the pot. The Australian bonsai growers insulate their pots with rockwool blankets to prevent overheating. First though, put the vine in the shade for a while and that will tell you if it is overheating.
If you have a space in the garden it would be better placed there and there are training techniques such as 'Vertico' or 'Mosel Loop' which take up hardly any room at all. I planted new vines in the ground in April and despite the droughts down here I have had to stop them at 2 metres. If you can't plant in the ground and you are serious about getting some fruit, put it in a much bigger pot.

Good luck, David