Four Arm Kniffin System for Growing Grapes
David Handley: I'm David Handley, vegetableand small fruit specialist with the University of Maine Cooperative Extension. Today we'regoing to be talking about a simple system for pruning hardy grapes here in Maine. The pruning system I like to use is very simple.It keeps the plant open, so it gets light in the summer time, but it also protects theplant a little bit in the winter. This system works best with concord type or labrusca typegrapes, which are the grapes that tend to grow best in Maine. There's really a couple of systems that willwork well for labrusca type grapes. The first
one I want to talk about is the four arm kniffin,and that's what we're going to prune first. The four arm kniffin consists of a perennialtrunk, which goes from the ground right up to a top wire, which is set at about fivefeet. Coming off of this trunk, we will have four arms, or canes, oneyear old growth.Two on the top wire, running each side of the top wire, and two on a lower wire. Thislower wire should be set at about two and a half feet off the ground. Every year, we're going to come in and pruneit so we continue to have a perennial trunk, but only four one yearold trunks to producethe fruit.
Here is our permanent trunk. You can see here,this is a cane from last year. Two yearold cane, this was our fruiting cane last summer,and you can see the difference. Here's this year's cane, that nice chocolate brown colorand smooth bark, and here we go with the older cane, the two yearold cane. The bark is startingto peel, and has more of a gray look to it, so we know that this particular shoot isn'tgoing to fruit again. It's the one yearold shoots that come off it that will fruit. This is going to get pruned out, so that wecan keep our fruiting wood closer to the trunk. We'll just take that back to a good fruitingshoot, and we'll start to cut it out. This
is where it gets fun. We need to wrestle thisout of the trellis, and of course, all these little tendrils have tied it up and aroundmost of the growth that's there. It takes a little bit of cutting, but be careful notto break the fruiting canes that you want to leave behind. Pull it off, and that will open the plantingup so we can see what we have left for good fruiting wood for this year. We've taken offthe four fruiting canes that we left last year, and you can see pretty much all that'sleft, at this point, is the green shoots from last year, that will provide us with goodfruit for this year.
Now we need to choose which four we want toput up. We're going to have four canes. One, two, three, four. Two for the lower wire,two for the upper wire, each heading off in different directions. What I want to look for in this case is canethat's got this nice chocolate brown color, and is about 38 of an inch in diameter. Aboutthe width of your little finger. If it's thinner than that, if it's very weak, it won't producegood fruit. Thin stuff like this, less than 38 of an inch in diameter, we'll just cutthat right out. Here we've got one that's going to go in thisdirection, that looks very nice. I'm going
to count, remember we want about 10 buds onit, so we'll count our buds. One, two, three, four, five, six, seven, eight, nine, 10. ThenI just cut out beyond that, because the weaker stuff at the very end isn't going to producevery good fruit. I have my four arms, but you can see I stillhave some leftover canes. What I'm going to use these for are what we call quot;renewal spurs.quot;I'm going to cut these back so that they just have one or two buds on them. What I'm goingto use these buds for, the green shoots that will emerge from these buds and grow out,will be the canes that I'll be putting on the wire next year for fruiting. We call thesequot;renewal spurs.quot;
We have plenty of wild concord grapes on ourproperty. However, the insurance company doesn't approve of our harvesting methods so it'sprobably best to plant some cultivated grapes. When I cleared the land for the greenhouse,it left plenty of area to plant various fruit producing plants which don't need the greenhouseto thrive. Plus why waste the space just growing grassé Taking a look at my 3rd grade drawing skills,I'm going to set three 4x4x10' treated posts 34 feet into the ground and space them 24'apart. This will allow for 8 plants in the space. Then I'll string 12 gauge galvanizedwire starting with the first wire 4246quot; from
the ground, then space the other two 12quot; apart.The plants can be spaced 6' apart and over time the vines can be trained along the 3wires. I had planned to set the posts first in theevent that I hit any large rocks while digging, however I blew a seal on the backhoe and hadto find some parts for it. So I took my chances and put the plants in first. The row shouldgo in a straight line and a 100' tape measure works well for marking out the locations ofeach post and plant. Jamming a piece of survey's tape at each mark does the trick. We're goingoldschool and using a pickaxe and shovel and digging a hole about 1 foot deep. Luckilythere weren't any large rocks in the way just
a few roots and small stones that the pickaxewas able to pluck out. Later, looking at the post holes, you'll see why I didn't dig themby hand. Planting the vines is fairly easy. I got theseseedless concord grapes from Gurney's for half price. I just remove the fiber that'sused for keeping the roots damp, spread out the roots a bit, and set it in the hole sothat all the roots that emerge from the vine will be just below the finished level of thesoil. All the dirt that came out of the hole was hardpan so I filled it with nice organicsoil, then compacted it down, and gave it a really good watering. It also importantto cover the area with mulch to help maintain
the moisture in the soil until the roots canget established. These will get watered every day for a couple of weeks. The actual work of planting the vines is quick.It's the preparation of digging out the rocks that takes all the time. A 30 cent Oring and a day to dismantle andreassemble the valve assembly and the backhoe is running again. I can now install the postsfor the wire arbor. It may not be the fastest backhoe, but it beats digging through therock with a pick and shovel. The holes are dug to about 4 feet which will provide a deepenough anchor to prevent the posts from leaning
from the future weight of the vines. Someof the rocks that I pulled out where bigger than the hole. If I had to dig these by hand,I probably would have only dug down a couple of feet, and then would have to anchor theposts with concrete and guywires. It seems like a really big hole for a post,but without an auger with rock drilling bit, it's probably the easiest way to set a post.A little cleanup at the bottom of the hole and it's ready. I'm using 4x4 treated lumberrated for direct burial. I'm not a fan of using treated lumber, but in order for itto last a long time, it's a necessary evil. I like to add two temporary cleats to thepost to help support it while I'm set it plumb
and backfill the hole. I also like to dropa few rocks around the base to hold it in place when I start to fill it in. I'll fillthe hole several inches at a time and compact it between each layer, then clean up the areawith some more woodchip mulch. The first wire starts roughly 4246 inchesfrom the ground and the second and 3 wires are spaced 12 inches apart. It will be theperfect snacking height for the deer. At each marking I'll drill a 38quot; hole through thepost and then put in a 516quot; eyebolt. The back side has a large fender washer and nut.Having a large washer will help to keep the nut from pulling into the post under the weightof the vines. It's fairly important to make
How to Prune Grapes Summer
Hi, I'm Tricia, a California organic gardener and today we're going to talk about summer maintenance for your table grapes we've had an extremely wet season thisyear and my table grapes have gone bonkers I'm growing four different types of tablegrapes here and there's a lot of vegetative growth making for a very densecanopy over the grape vines earlier in the spring, the shoots were thinned when they were about six to twelve inches long you should have about six to eightshoots per foot of canopy at the same time as thinning the shoots, I also cut the suckers off at the trunk
and i'm going to continue to trim these suckers throughout the season, as necessary you see there's not enough sunlight getting into this little fruit clusters the sunlight is what helps improve theflavor and the quality of the fruit by having so much foliage around thecluster, I'm also at risk for disease the first step is to take these long shoots and tuck them into the trellising and keep them out of the fruiting zone that helped a lot but you can see there'sstill a lot of hanging vines I'm going to trim back this shoot that has no clusters on it
if you're going to trim back a shoot that has clusters, be sure and leave about 1517 fullsized leaves before you make your cut cut as little as possible and try to cut atthe point where the leaves are half the size of the mature leaves these smaller leaves haven't startedproducing food yet so the vine won't miss them as much asit would miss these larger food producing leaves the grape vines are looking a lot better the cutting is going to stimulate the growth so you don't want to do this too late in the season if the fruit is just beginning to ripen,it's too late to cut
now that I've tamed the vines, it's time to thin the fruit cluster thin when the fruit has just setand before it gets too big for goodsized table grapes leave onecluster per shoot in order to improve the size of thegrapes, snip off the very bottom of the cluster I'm happy to have completed my summermaintenence on my table grape vines now I look forward to grape jam, grape jelly,grape juice, and those frozen grape treats so enjoy your grape vines and Grow Organic for Life!.