The Vatican has no industry or agriculture. They do sell some religious items and souvenirs but few, if any, are produced in the Vatican.
Certainly blueberries and potatoes are two of the main agricultural products. However there is no evidence that hay is a "main" agricultural product of Maine.
Your cat
Beef.
The main industry is production of coins
There is no river in Vatican City but the Tiber River is quite close.
Lamb and milk.
Rice ftw
palm oil
Italian, though many languages are spoken there.
Wool, sugar, meat, fruit, and cotton would be the main agricultural products.
Dairy and Wheat
Fruits and Beef