Easy Salad patches:
You can easily make patches by gluing sticks in rows onto a big base. then cover up everything with Sand and paint it. (EDIT: Just as Captain Blood described

)
The Salad plants can be easily made of wedding-decorations (I'm using small roses made from paper. You can buy them cheap on ebay).
Easy Corn Fields:
To make easy Corn Fields you could use rough doormats. You don't even have to paint them.
Pumpkins can be made of Greenstuff. Just form a small orb and carv very thin lines into it.
Wedding-Decorations used as Salat Plants:
