Some good cotton dishcloth patterns for a country kitchen include checked, plaid, gingham and a two-color stripe. A truly rustic look might include plain or solid-color cotton dishcloths, similar to the ones sold by Country Cottons or other retailers.
The country kitchen aesthetic often features wood or exposed wood elements, and harkens to a simpler time when woven fabrics were made by hand. Simple patterns are the rule, often plaids, ginghams or stripes in reds, blues or other basic colors. A solid-colored dishcloth would fit in a country kitchen as well, and might have a simple embroidered element embellishing it.