Daffodils are perennials which flower in the early spring and start to wilt over the summer. Daffodils use much of the sunlight and nutrients to grow the bulbs which stay underground. This is the reason that after a few years, the number of bulbs grows large enough to be overcrowded and inhibit flowering and plant growth. By early fall the leaves will have started to fade away where the bulbs can be dug up and harvested.
Harvesting and preparing the bulbs for storage
Daffodil bulbs can be dried and stored over the winter to be sold or planted the following season. It is always a good practice to allow the flowering and foliage to wilt and rot away before digging up the bulbs. This is to ensure that the bulbs get the maximum amount of energy for the photosynthesis from the leaves before they are harvested from the ground.
Using a shovel or pitchfork, dig up the bulbs, taking care not to damage them. Shaking off the soil and spread the bulbs out on newspapers to dry for a couple of days. After drying for a bit, the bulbs can be placed in net bags and hung up to maintain the drying process. Store bulbs in a cool dry place and they'll be ready to plant the following season.