After a couple of recent missed/diverted deliveries to plot tenants on the allotment site. Here is a definitive delivery address for the Allotment Site that actually works.

You should probably still indicate to any delivery service that the gate is set back from the road and that it does not have a street number.

Reading Road Allotments, Reading Road, Woodley RG5 3AA

You can also use the Website/App What3words and that ‘address’ is powering.lance.rating