I have waited nearly 3 months for the planners to let me know if pp is needed for a polytunnel.
After sending them numerous reminders I finally got their response today.
In reply to your emails, it does appear that planning permission would be
required as the proposed use from your description would be domestic associated
with your domestic enjoyment of your property. The growing of vegetables etc is
not development in itself and does not need planning permission, however, when
structures begin to appear on the site (outside your domestic garden area) and
remain on site for more than 28 days then it becomes development. When the works
count as development the use needs to be assessed and in order to be
agricultural it must have a commercial element to it which your proposal does
not. Furthermore, even if it were counted to be agricultural development the
amount of land you have within your ownership would mean that planning
permission would be required for the structures regardless. If you were to
relocate the polytunnels within your garden area then planning permission is
unlikely to be required.