We search the whole countryside for the best fruit growers.
You can let each supplier have a page that he or she can edit. To see this in action you will need to create a users who is in the suppliers group.
Create one page in the growers category for that user and make that supplier the author of the page. That user will be able to edit his or her page.
This illustrates the use of the Edit Own permission.
Customers and suppliers can post their favorite recipes for fruit here.
A good idea is to promote the use of metadata keywords to make finding other recipes for the same fruit easier.
To see this in action, create a user assigned to the customer group and a user assigned to the suppliers group. These users will be able to create their own recipe pages and edit those pages. The will not be able to edit other users' pages.