Daio Wasabi Farm
The Daio Wasabi Farm is near Matsumoto (about 25 mins drive from the city). It's one of Japan's largest wasabi farms. Taking a quick trip from Matsumoto after seeing the Matsumoto castle was a great stop to see how wasabi is grown.
Here you can freely walked around the farm and sample all the different wasabi related products such as wasabi ice cream, wasabi croquette, wasabi lollipop, etc.
Wasabi plants growing in a fresh running stream. The wasabi is grown under black tarps to protect it from the sun and the crop is watered by spring water. It takes 2 years for the wasabi to mature.