The best time to dig daffodil bulbs is early summer, after the blooms are gone and the foliage has faded. Whether you want to move them to a new location or just separate them to control crowding, plant them right away, if possible. If you can't plant them immediately, store them until the autumn planting season or even until the next spring; The daffs may not bloom in the first year if you plant them in the spring, unless you store them properly. Dig them carefully to avoid bruising the bulbs.
Shake the dirt from the bulbs and gently untangle the roots to separate them. Don't break or cut them apart. Discard any bulbs that you accidentally damaged, because they may rot in storage. Cut off the dead leaves 5 cm (2 inches) above the bulbs.
Spread the bulbs on a screen in a warm dry place, not in direct sunlight, for two to three days to cure them.
Place the bulbs in mesh bags and hang them in a place with good ventilation and low humidity, out of direct sunlight, with temperatures between 10 to 21 degrees C (50F to 70F) until the autumn planting season.
Place the mesh bag of bulbs in the fridge for 12 to 16 weeks if you need to store them over the winter, or hang them in an unheated area sheltered from rain where they'll receive similar cold temperatures. Without this cold treatment, daffodils may not bloom in the first season or may give small blooms on short stems.
Even without cold treatment, bulbs will grow if you keep them over the winter in a mesh bag at 15 to 20 degrees C (60F to 68F) and plant them the next spring. You may need to wait for the following year to see blooms.
Avoid storing fruit near the bulbs, since fruit-produced ethylene gas can prevent blooming.