Cucumbers are 96 percent water

True - see here
Others

Strawberries (92 percent water)
Grapefruit (91 percent)
Cantaloupe (90 percent)
Peaches (89 percent)
Raspberries (87 percent)
Pineapples (87 percent)
Apricots (86 percent)
Blueberries (85 percent)