In temperate regions, daffodils are a sure sign of spring. Every fall, gardeners plant daffodil bulbs. The following spring, they are rewarded with golden flowers. Some daffodils return faithfully year after year. Unfortunately, other daffodils bloom for only a few years. The biggest difference between daffodils that return annually for a decade or more and those with short lives is daffodil bulb nutrition.
How the Bulb Functions
Daffodils, like many bulbs and tubers, flower in the spring. They can do this because the bulb actually stores nourishment from the previous year's growing system. Daffodils don't have to wait until the leaves and roots have gathered enough nutrition from the current growth to produce flowers. However, the bulbs have to store nourishment each year if the plant is to produce flowers the following spring.
Add at Planting
Daffodils thrive when planted in a sunny location with well-drained soil. Most gardeners add a little fertilizer when they plant daffodil bulbs in the fall, to encourage root development before the ground freezes and to be sure plenty of nutrients will be available to the plant in the spring. Commercial "bulb food" fertilizers are widely available for this purpose.
Established daffodils benefit from a little extra nutrition during their annual growth cycle. When the tips of the daffodil are protruding from the soil, scratch in a little fertilizer that has more potassium and phosphorus than nitrogen, such as a 5-10-10 mix. When the daffodils flower, side-dress the plants again, this time with a 0-10-10 or 0-0-50 fertilizer. Never use a fertilizer that is high in nitrogen.
Feel free to cut daffodil flowers for display in the house. It won't hurt the bulbs in any way. When the uncut flowers wither, deadhead them before seed pods appear. You want the daffodil to put its growth into a large bulb for next year's bloom, not into seeds that will take several years to grow into new blooming daffodil plants.
Daffodil foliage does look untidy after the flowers have bloomed, and gardeners are often tempted to cut it right away. Resist that temptation, because the leaves are still gathering nourishment, and the bulb is still storing energy for next spring's flowers. Don't cut the foliage until it dies back naturally.
Most daffodils naturalize readily, although some types are better at this than others. Daffodils reproduce both by seed and by bulb division. If you want your daffodils to naturalize, let the seed pods form, burst and distribute seeds on their own. Fertilize a little more heavily than you would otherwise, to be sure the plants have enough nutrients available to develop seeds while still replenishing bulbs.