Daffodils are an easy to maintain flowering bulb and require division only after they become crowded. If planted with a generous amount of space they may only require division every five to ten years, if that. You will recognize crowding when the flower blooms are smaller and the plants begin to grow in height at different levels.
What Time of Year to Divide Bulbs
The optimal time to divide daffodil bulbs is in the spring after they have bloomed. Dividing them while the foliage is still attached is a great method to identify the bulb's location to avoid damaging it while digging.
How to Move Daffodil Bulbs
Remove spent blooms but leave the green foliage intact.
Dig around the base of the plant carefully using a digging fork to decrease the chances of cutting the bulb, which will allow virus and disease to enter.
Remove the bulb from the soil with the foliage intact. Holding by the foliage, shake off excess soil. Break or pull the bulbs apart if necessary. Plant as soon as possible.
Plant in fertile, well-drained soil. If your soil contains clay dig in organic matter such as peat moss eighteen inches in depth. The general rule of thumb for the depth to plant a flower bulb is to dig two to three times as deep as the bulb is tall. On average, this would mean a daffodil bulb would be planted about 8" deep.
Fertilize with a 10-10-10 compound or rich organic compost. The fertilizer should be added to the soil several inches below the bulb's position so the roots can access the nutrients.
Leave the greenery on the plant until it has completely dried, then remove it carefully by hand.