These are just some random ideas after spending an hour on the site:
- Friends! it would be great if I could friend someone!
- Friends feed, on the home page (once logged in) having a list of updates from people I'm following.
- Post comments: replying to a comment is a bit odd, I can only reply to the OP and am taken to a view where the comment I want to reply to is not shown.
- crops.json would be great with an image URL for visualisations.
- community gardens, allow me to invite other members to my garden an leave comments/photos.
- RSS feeds! everywhere!
- Tweet/FB this links on my crops
- Garden notes/photos/posts. Let me post pictures of my garden, post updates to my garden (with pics) etc.
- Enable CORS http://en.wikipedia.org/wiki/Cross-originresourcesharing to allow 3rd party mashups
.. ok I really should pitch in at this point c_c;