Is it good to snap off the ends of extremely vigorous shoots now that are over 10 leaves? Would this re-direct energy to needier shoots and free up canopy space?
Some table grape growers will ātipā (snap off the tips from) their shoots to encourage larger clusters, very similar to pinching with figs. Iām not sure tipping your vigorous shoots will divert the extra vigor to shorter shoots, but it might. It might also just encourage laterals which will clog up the canopy at the point from which they emerge. Itās worth a shot if you have the time I suppose.
I have yet gotten the chance to talk to a guy nearby who grows fabulous grapes in a similar condition. But when I looked at his vine I could see he did indeed snap off shoots for uniform lengths. Heās got a very compact setup under polycarbonate. Appears to have also trimmed the flowers at the top, leaving about the bottom half in a compact bunch. I know the size and location would make it better for bagging, possibly ripening in a similar pace as well.
As for my vine, the rainy season starts today, preceded by a long dry spell. I think I didnāt give it enough water, particularly with the extra canopy I have on it this year, and two days ago I noticed many of the flowers have browned and died. Iāll give it a few days of rain before I go in and start cutting bunches and newly bunchless shoots. The spacing on whatās left of some of the bunches is not ideal for bagging. May have a poor year for grapes.
Is this what grape flowers without enough water look like?
Water stress can cause flowers to abort but do you see any other signs? Are tendrils shriveling? Poor fruit set can be caused by a number of things. Lack of nutrients (boron plays a big role in grapes) or inability to uptake due to excess of another nutrient, rain causing the caps to stick, or too many clusters, are some of the main reasons.
A few tendrils and shoot tips withered, but not too many. Being very dry until now, so shouldnāt be humidity. Iāve only added aged chicken manure, so no other nutrients. Not sure about a boron deficiency, although preceding years didnāt have this kind of problem.
Too many flower clusters? I wanted to cut and trim flowers earlier, but it was unclear whether it was safe to do so. Every guide I have seen shows cutting clusters out Well after the fruit has set.
When I touch the vine now many of the borderline fruits are falling off.
Iām thinking I should wait for a few days and let the vine soak up the heavy rains, and see which clusters have been able to recover at that point. Then do a thinning.
Since the clusters may be much smaller, Iām wondering if I should leave 2 per shoot.
So far so good. First harvest today. Most of the Kyoho are ripe now. Excellent taste, better than store bought we were given today. Pione appears way behind, still lots of green grapes mixed in. Weāll see if they can beat the leaf drop.
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Not sure if anybody knows the answer, but at what point does thinning grapes not help with ripening?
If youāre asking timing in season wise, then thinning after veraison is generally pointless. The sooner you thin the greater the effect.
If youāre asking how much to thin, thereās a more complicated answer that would involve # of buds, ravaz index, berry/cluster size, etc.
My Pione vine appears to be overloaded. Most are still green, should be harvesting now. Wondering if any use to thinning at this point.
Yeah I wasnāt very precise beforeāthinning post-veraison can help the plant by allowing it to build up its carbohydrates for the winter (by reducing the carb cost of the fruit). But yeah it wonāt help the other fruit ripen any faster.
In the commercial world theyāll thin right up to harvest but itās to prevent the unripe fruit from being picked by a machine harvester, or to reach an agreed upon cropping level.
How many feet of cordons can onw root system support?
The wall of the cage that holds my blueberry bushes measures 18 feet wide by 8 feet high and is covered by chicken wire and is open to the sun all day.
If I plant one grape plant in the middle, can I develop a 6 arm espalier with the permanent structure consisting of 3 nine foot cordons on the left and 3 on the right?
Will one root system be able to support and feed this design?
Would it be better to plant 3 different vines?
Thanx
Mike
Thatās a tricky one. Assuming itās a vigorous, disease resistant variety (like a Concord say), one vine could definitely cover 18 feet. Iām not sure about 6 cordons though, that sounds like a lot of buds and possible congestion (excess of leaf layers). Commercial Concords carry in the range of 80-120 buds, so maybe if you kept the cordons pretty clean it could work. Iād say start with your one vine in the middle, establish your first set of cordons and build from there. Youāll known youāve pushed too far (say on your second or third set of cordons) if the new shoots are wimpy looking.
Thanx
Mike
Funny enough hereās a vine I came across this morning. Extends almost the entire panel which is a little over 18 feet. Riesling, close to Lake Ontario, with a regular spray schedule.
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Thanks very much, makes sense.
I made verjuice a few years ago. Was hard to use it up. Wondering if green and greenish grapes can be used somehow.
My problem the last couple of years is most of the nicely spaced trunks/cordons have no growth - everything flying out of a couple of spots creating a rats nest of overcrowding. Last year I lost most of the crop due to mildew, undoubtedly aggravated by crowding.
Are you able to share a picture? Thatāll help cut down on speculation.
I may be able to get a picture in a couple of days, not sure if it will help much. just seems like sections of the vine are dead, and most of the growth is coming out of a couple of spots creating crowding.