Some things you could use Twitter for:
-- real time updates to your customers about the condition of crops, i.e. "this is the last week for blueberries at Piotrowicz Farm!"
-- real time updates from a farm stand or farmer's market. "I've got five heads of bronze arrow lettuce left at the West End Market."
-- talking to (and about) legislators if there's a bill coming up that affects you.
-- to give and receive real time information about weather
If you do Twitter, it makes sense to learn more about hashtags.
One general thing to remember: the news media now troll Twitter and other forms of unpaid social media for news ideas.