i've been given a couple of cuttings from a grape vine and would like to grow them in my polytunnel, i'd rather not poke a hole through the tunnel to have the root outside so was wondering if it would be ok to grow them in the borders, do you think that two vines would be to much in a 15'x10' tunnel ,i was only planning on having one but was given two plants :)
Planting them inside the polytunnel will be fine, I'd plant both then get shut of the weakest one when you need the space.
One of my lotty neighbours grows beautiful peaches in his polytunnel, :)
Sat and thought about this......Grapes in a Polytunnel.
Polytunnels tend to be hot in the summer cold in the winter, you should change the skin about every 5 years and the soil every 3 years unless you remove the skin to allow the soil to be flushed through then replace it, so will the vine survive during that period.
The vine will have to run well away from the skin to avoid damage.
Tunnels create a lot of humidity which can rot the fruit so good ventilation is required, will this affect any other crops you grow in it.
Watering is not a problem as the vine can be planted at the base of the skin so it get the water running off the tunnel, then trained to where you want to run it.
On my tunnels i have the south side netted from the base to about three up the side and the full length of the tunnel so i can open it in the summer for extra ventilation and close it in the winter if i need to. I also have polythene doors at the rear which can be opened and closed as needed so i can control the humidity as i want it depending what i am growing. To grow grapes i think you would need something similar.
Hopefully there is someone who does grow grapes in a tunnel can give you more advice than me.