Summer grape vine pruning


Hello all
I have a table grape vine that I have sent the clusters to one per branch. I have the entire fine covered to protect from excess mildew etc rain damage.
Some of the branches are shooting out quite far past the roof. Is it better to leave them uncut as they will feed the grape bunch better? Or can I cut them back, leaving about 3 feet or so of branch for the grape cluster?


I believe it is recommended five feet of vine to ripen a bunch of grapes.


Is there any harm in letting the vine grow as long as it wants?


My neighbor heard I should cut off all the growing vines past the last grape bunch. Was she full of it and a know it all neighbor, or is she right?


Regarding letting the vine grow as long as it wants, don’t let them touch the ground. Regarding what the neighbor said, what advantage is there in cutting off your vines? One should leaf pull near the bunches to aid ripening, let sunlight in, and allow air to circulate.


OK thanks, so there’s no conservation of energy by pruning?


Plants need leaves to produce energy… So it makes no sense to me to prune leaves in order to help ripening. I understand a grape vine may put out way to much growth in one year if your training it onto some sort of smallish trellis. If you want high production (vinyard), you should have more plants (getting energy from more root systems) in less space so that the plants can produce a good amount of fruits and you should prune whatever growth you don’t need. Anyway, I’m fairly new at this and this thread is very interesting to me. I’d love to learn more.


There is a give and take with grape plants. Initially in the spring they draw from the carbohydrate reservoir stored in the roots from last year. Then there is a switch and the plant begins to replete the reservoir once again. There is a direct relationship between pounds of vine produced this year, and pounds of grapes next.


I have different grape vines on overhead trellis. I let them grow all they want, and never spray anything. In 2017, with so much rain I lost a lot of fruits to disease. This year, when the fruits started forming I continually snip off the leaves touching the fruits, and where the vines are too dense to let the sun light in. So far there is no mildew or fungus problems even with all the rain and cloudy weather. If they survive any heatwave during summer, I will net the bunch of grape later when the fruits change color because the birds can see them clearly. Netting early will result in aborted fruits in the net causing disease and ants problem.


Here is my trellis:

Some guy up the road has a grafted Seto Giants vine, very compact and high quality production, in his car port. The shoots with grapes are kept to about 3 feet. There’s an interesting double T shape to the main vine. Rain cover and pesticide sprays seedless treatment etc.


I did some mild pruning and bagged all the grapes. Minimal insect damage so far. This will be my first and best shot at getting good grape harvest after several years of trying. I’m not going to use insecticides or fungicides in my garden anymore, so I’m hoping for the best.


I am a little concerned about your bags. They look so dense. The grapes needs good air circulation to prevent mold and fungus, especially in humid weather. I put just one tulle bag on a bunch to test, and had to remove it a few days later. Like the last few years, I will use this type of bags on mine when the grapes change color, maybe double bagged if the bunch of grape is too big, and secure with a clothespin at the stem end. The green color will blend in to hide the fruits, and discourage the birds somewhat. Under the sun, this type of bag will only last one season.


I use paper bags, somehow they protect the grapes so that they don’t get wet, even when it rains. You can put them on as early as you want.


The Japanese use wax paper on each individual cluster in a semi-commercial setting. They also have a couple other systems that use either plastic draped on the side in the fruiting zone, or over the top (all to battle excessive rain).


For me the problem in socal now is the long, dry summer heat, or a heat wave. Last two weeks or so I have let the branches grow up to provide some shade for the fruits. I don’t know if I should try the paper bags, since I had pears and apples steamed in ziploc bags, even with the bags perforated and the bottom corners cut out. I would appreciate any comments on this. Today a lot of birds suddenly came, aiming for the grape vines. There was no time for bagging so I put pinwheels on the trellis, both upward and swinging down. The birds all went away for the rest of the day. Hopefully they won’t come back soon.


Speaking of which, we have had downpours of rain in July. Unusual for WA state. I wonder how all this water will affect taste of grapes and tomatoes?


After a two-day trip all the grapes are still there, so seems like the pinwheel did help. I didn’t want to put them on until now because there were some large birds that may scare the squirrels away. These are similar to the types I use. They are about 10 inch in diameter. I like the round type better since they are trouble free. On the other type, I put a drop of crazy clue on each metal spot where the blades connect to the center, or the blades will break off and fly away in strong wind. I usually buy them before Memorial Day at the dollar stores. The best ones are of sparkle mylar material that reflects the sun light, and will deter the birds even when there is no wind. We are on the hillside with a lot of wind. Otherwise I don’t think this will work well if you don’t have much wind in the yard, because the birds will get use to them.
We stopped by Bay Lauren and brought back a Sugar Twist pluerry and a Harko nectarine that have some fruits on. The nice girl reminded us again that they may not fruit in my area, so we told her that we would take the risk since the fruits are so good.


Some of the Thompson seedless are ready, small but very sweet. No loss to disease or birds this year.