Frozen and Lost Buds

[NDengineer]

I need some help deciding how to prune my vines this year. this is year 3 for my marquette grapes, and I lost at least 2-3 sets of buds due to spring frosts and snows. All spurs were budding earlier in the year, but froze. Each of the vines is still alive and growing, but not where I'd like.

I live in front range Colorado (Denver area), and am using a double trunk top wire cordon trellis. Some trunks have no growth showing anywhere on the cordon or spurs, and only from the base of the trunk. Others have a few shoots coming out midway on the trunk. Some have a few shoots coming from spurs, but only a few of the spurs and not all of them.

Do I need to cut down some of these trunks and retrain them from scratch? If I leave a trunk and cordon up, but new shoots only grow out of 1 spur, will it have new buds the length of the cordon next year for new spurs?

Pictures attached.

 

[grapeman]

That tends to be a problem with Marquette some places. It begins to grow and if any late frosts come, the buds freeze. I would let them grow and see what will grow back. If they don't adequately regrow, then cut the trunks back and bring them up again.

 

[treesaver]

I am of the opinion that they will push new buds, but not certain. I say this because, my frontenacs and nortons both just keep pushing buds on the trunks, after I rub them all off, they keep putting them on! I would probably be keeping the trunks cleaned off, to force the vine to put it's energy into growing on the cordons. Be interesting to hear what Rich has to say on that!

 

[NDengineer]

Grapeman and treesaver, thanks for your responses so far. I'm hopeful that they'll keep putting on buds, and grow from the spurs or at least the cordons like I want them to.

I'll try removing some of the shoots at the base of the trunks, but I'm hesitant to remove all of them in case no buds break on the upper trunk or cordons. I wouldn't want to unnecessarily kill a trunk and have to wait till next year to regrow it.

 

[grapeman]

I am with NDEngineer on this one. Keep you options open with a shoot or to as a trunk replacement if needed. If the cordons recover then you can remove the spare shoots later but if it doesn't then you need to wait for it to begin from shoots again.

 

[NDengineer]

UDPATE:

Most of the vines continued to produce new buds, though they've typically sprouted from the cordon, and not the spurs. Some cordons aren't growing any shoots from the outer 1/2, so I may need to regrow part of the cordon if no buds form at the end of the season. I didn't need to regrow any trunks though!