The 6 Things You Need to Know About Spring-Flowering Bulbs

Remove mulch. Last fall you will have added a nice layer of organic mulch to protect the bulbs during the winter. Pull this extra covering off of the bulbs, particularly around very short bulb species, relocating it to other areas of the garden or stashing it in a compost pile for use in the garden throughout the year.
Once the flowers have faded, deadhead them. This allows the plant to focus on restoring the reserves of the bulb instead of dedicating energy to the production of seeds.
Leave foliage on the plant until it turns brown. The bulb needs the foliage to gather energy to replenish the bulb so the plant can return next spring.
Spring often comes with ample rain to sustain your spring-flowering bulbs, but should there be a dry period, watering is recommended.
Fertilize your bulbs, but avoid mixes high in nitrogen. According to the University of Illinois Extension, in the fall add a 10-10-10 soluble fertilizer plus two cups of bone meal to the garden. Repeat this once the foliage breaks through in the spring. Also, phosphorous is needed to encourage root growth. Carefully work the phosphorous into the soil, ensuring it reaches the bulbs’ root system.
Some bulbs, such as daffodils, develop thick stands of plants. Every few years, carefully dig, divide and replant those bulbs.

Photo of the Cincinnati Zoo & Botanic Garden