Farmer's

I assume that this sign is directly addressing farmers to inform them that this store has everything they need for plants and for animals. The quotation marks are unnecessary. Quotation marks do not add emphasis or show direct address. Additionally, the apostrophe is unnecessary because there is no possession nor is there a contraction. The sign should be written as follows: Farmers, everything for your plants and animals. 

Another possibility is that the sign means to say that this business, named Farmer's, has everything for your plants and animals. In this case, the quotation marks are still incorrect. 

As another issue, since the business caters to more than one farmer, the appropriate punctuation of the title should be Farmers'. On the business' website, the word is punctuated correctly. I did not take a picture of the sign on the side of the building that contained the same incorrect punctuation. 

http://farmersassociation.com/location.html

This sign from the same business fails to capitalize the name Dale.