The 'Roar' hitmaker - who split from John Mayer in February after two years of dating - admits she finds it ''relaxing'' growing her own fruits and vegetables.
She is quoted by The Sun newspaper as saying: ''It's [gardening's] so nice, it's so fulfilling to go pick your dinner, bring it back and make it. It's relaxing and very fulfilling.''
The 29-year-old singer also likes to make sure she absorbs nutrients and believes drinking lots of fluids throughout the day is key to keeping herself healthy.
she said: ''I take a lot of vitamins and I drink a lot of water.''
Meanwhile, the brunette beauty, who was married to Russell Brand for 14 months until December 2011, is also a fan of keeping fit, and last year started channeling her energies into going spinning - a regime of tough indoor cycling classes - at the gym instead of going out clubbing.
A source said previously: ''Katy believes the workouts have really been soothing her brain.
''A few years ago she would have released the energy by hitting the clubs and dancing the night away. But she's getting older now and wants to do things healthily.''