There are many farms in Fukuoka and the one we visited was Lion Kajitsuen (らいおん果実園). They have many different varieties of strawberries so don’t go crazy chugging them down as soon as you see them. For a fixed fee, you can cut and eat as many strawberries as you want. You can even choose to pack the extra ones home for a minimal fee. I was quite done after my 5th strawberry but the boys kept going on and continued to have the packed ones the day after.
If you have kids (or are totally willing to indulge in your inner child), this is a must-do. As the saying goes, ichigo ichie ("one chance in a lifetime").