Prepare a sunny planting area in the autumn before the first autumn frost. Work the soil to a depth of 1 foot with a garden spade. Add 1 to 2 inches of soil sulfur to the top of the soil if it is more alkaline than acidic. Rake to smooth the surface of the planting area to finish preparing the soil.
Dig holes for the daffodil bulbs so that the tops of the bulbs will be 4 inches beneath the soil and the base of the bulbs 6 inches beneath the soil. Optimal bulb spacing is 6 to 12 inches. Plant the bulbs closer together for an impressive daffodil display, understanding that the bulbs may have to be dug up more often if they are planted closer together.
Place a daffodil bulb into each prepared hole with the pointed end facing up. Cover the bulbs with soil and firmly pat the soil down. Water the daffodil bulbs generously immediately after planting. Keep the planting area moist in the time between planting and freezing weather to ensure that the new daffodils grow sufficient root systems.
Mulch the growing area with 2 inches of shredded mulch after the first autumn frost.
Sprinkle a 5-10-10 granular fertilizer on the soil around the daffodils immediately after the foliage emerges from the soil in the spring. Consult package recommendations for fertilizer amounts for the size of your growing area. Fertilize the daffodils again when they begin to bloom, this time with 0-10-10 fertilizer.
Continue to water the daffodils if the spring weather is dry to ensure help them keep growing properly.
Remove the blooms immediately after they fade and leave the foliage intact. Do not cut back any foliage until approximately two months after blooming is over. Remove the foliage by hand when it wilts and turns yellow. Do not use a pruning shears or scissors because this may spread bacteria among the daffodils.
Dig up daffodil bulbs every five to 10 years if they have been spaced between 6 and 12 inches apart. Dig up daffodil bulbs every three to five years if they have been spaced closer together. After removing the foliage, remove the bulbs from the soil. Shake off the excess soil and dry the bulbs for several weeks in a single layer in a cool, dry location.
Examine the bulbs after they dry and remove offsets from the main bulbs. Offsets are smaller bulb growths that can be snapped off and planted separately. Place the dried bulbs in a cloth bag and store in a cool, dry location until you are ready to plant again in the autumn.