when? all depends if you mean to keep them and eat them or rid them.
if you want to harvest some then usually Grapes generally mature from late August to late October depending on what variety, however it doesnt hurt to keep trying one for sweetness and ripeness, if you have green ones they become sort of see through or more lighter.
if you mean prune as in cutback then you can do this anytime but preferbaly before it gets too cold or the unpicked grapes will rot and turn white and it gets a bit horrid.
leaves can be left to mostly fall off and collected up in jan-feb early march.
ANDY UK
The process is a long and varied one but I have included a link which explains it quite clearly. See the Related Linkbelow.
Cardinal grapes are pruned by the spur method. Rather than describe this technique, I have placed a link to a website that gives a clear explanation of the process.
Start by killing as many families as there are grapefruits. Then you use the corpss, and wrap them around the grapefruits and squeez all the juices out.
Pruning grape vines is rather a specialised horticultural procedure, and too complicated to answer here. I recommend close study of the many books and videos available on the subject.
no
The first seedless grapes were the Thompson green seedless grapes. All seedless come from this stock. They were discovered and not invented by Thompson.
there are lots of grapes
Colorado does not appear to have a state beverage at this time. Source: Netstate.com
Not to produce grapes but you need to prune them to keep them under control and produce good grapes. You should lead shoots along wires and cut every sideshoot out at the leaf after the bunch of grapes forms.
So they don't grow too big, and to remove unwanted parts, which may be diseased.
Thompson Seedless grapes are likely the best grapes from which raisins come. Dehydration can take up to 24 hours in a food processor.
not likely, you can however graft good grape varieties on the branches you want to cut
In the US the Thompson seedless is the most used. Others are the Black Corinth, Fiesta, Muscat and Sultana.
A "heppe" is a garden knife used to prune the trees, a small sickle, or a curved vineyardist's knife used in trimming grapevines in the wine country and in cutting grapes in the vintage time.
Whatch for a change of color such as blue and green to red and purple. Watch for color changes such as green to brown. Grapes will reach full size. Grapes have to be sweet. You have to taste them to be sure.
You can prune it but the symmetrical shape that makes it attractive will be wrecked. If you do prune only tip prune.
Yes. Thompson seedless and Red Ruby require hot weather to grow. These are table grapes and need the heat. Wine grapes can grow in a warmer climate, but usually require a cooler climate.