Trellis problem...

[temery]

Here's my problem: I planted grape vines a few years ago, and they've grown fine. Initially I had the vines trellised along a wood post fence. This got knocked down by a tornado. I replaced the broken horizontal members, and these got knowledge down by the October storm. After all was said and done, the fence posts were beginning to rot anay way.

Last year I pounded in 3/4 " galvanized pipe. I first pounded in 1/2 " pipe - 10' pipe, 5' is in the ground, 5' above ground. The 3/4" pipe was place over the 1/2" pipe, 3' into the ground, 7' above.

I strung 14 gauge wire between each pipe at 3 1/2 feet, and at the top (7'). The pipes are 10' apart.

My concern is this - is this trellis system going to support the weight of the vines over time? It is fairly easy for me to move the top of each pipe a few inches in any direction. The wires between the pipes minimize this, but I am still a bit worried.

I am considering 4x4x12' pressure treated posts (10' apart) buried 4' and using 12 gauge wire. I'd rather not have to do it if the galvanized pipes are adaquate.

I also have a concern with using pressure treated wood - will it 'poison' the grapes? (I am told newer pressure treated wood is safe)

A secondary concern is in disturbing the roots of the plants if I were to pull the old fence posts and replace with the 4x4 posts (6x6 if needed).

My goal is to create an outdoor room as the vines begin to cover the connected wires.

Any thought?

 

[CARBOY]

Mmmmmm. A picture would be nice. Sounds like what you have may be Ok for a few vines if the end poles have anchor wires. Lots of small home growers use pipes or what ever is available. As for myself, I have several rows with 10 vines per row and because of the different training systems I use 4~5 inch row poles and 6~7 inch angled end poles with ground anchors. Recent years the pressure treated methods have changed due to laws. I use pressure treated poles designed for fences. I use 9 (or maybe it was 10) gauge wire for end pole anchor support and 12~14 for the row run to support the vines. But I was looking at long term from the beginning. Remember, basically the vine growth habit usually dicatates the trellis/training style. I'll include a picture of what I have in another reply. I have seen round pipe crease, fold and bend at the ground level. I also use tensioners and spring compensators on the wires.

 

[grapeman]

I think that 1/2 inch pipe is doomed to fail very quickly. You don't really have 3/4 inch since it is the half inch in the ground. Vines with a crop weigh a lot. You have the vine weight, the leaf weight and the crop weight. Factor in wind blown forces acting on the vines and the system will fall over. Yes it is work, but the 4x4 PT will be a much better long term solution.

 

[garymc]

When you say it's easy to move the pipes, do you mean you can push it and it remains leaning or that the pipes flex and return to upright? I would think a little flexing wouldn't be a big deal, but if they can easily be pushed over, that's not good.

 

[temery]

When you say it's easy to move the pipes, do you mean you can push it and it remains leaning or that the pipes flex and return to upright? I would think a little flexing wouldn't be a big deal, but if they can easily be pushed over, that's not good.

They flex a few inches, then return when I let go.

 

[temery]

How delicate are the roots of established grape vines (a few years old)? One concern is that I'll have to pull up the old fence posts, and likely have to dig out the hole to accept the 4x4x12 post. I had planted the vines right next to the post.

One last question: if I were to go with 4x4, or maybe 6x6 posts, do they have to be 10' apart? How far apart could I safely go?

Mmmmmm. A picture would be nice. Sounds like what you have may be Ok for a few vines if the end poles have anchor wires. Lots of small home growers use pipes or what ever is available. As for myself, I have several rows with 10 vines per row and because of the different training systems I use 4~5 inch row poles and 6~7 inch angled end poles with ground anchors. Recent years the pressure treated methods have changed due to laws. I use pressure treated poles designed for fences. I use 9 (or maybe it was 10) gauge wire for end pole anchor support and 12~14 for the row run to support the vines. But I was looking at long term from the beginning. Remember, basically the vine growth habit usually dicatates the trellis/training style. I'll include a picture of what I have in another reply. I have seen round pipe crease, fold and bend at the ground level. I also use tensioners and spring compensators on the wires.

 

[grapeman]

Is there any reason you can't put the new posts in halfway between the vines? That would get digging the hole away from the vine itself. How long are the rows? The posts could go 20 - 30 feet between them (max).

 

[CARBOY]

Just a few questions if you don't mind.
What type & variety of vine/s did you plant?
How are the vines trained currently...low wire, high wire?
How many vines is "a few vines"?
How far apart are the vines?
I agree with adding the posts between plants and at the end. You can use the existing poles to train to your top wire depending on the training style.
I have include a few pics from my wineyard. A few rows high wire, a few rows low wire.