Many plants have an underground root structure called a bulb. Common bulbous plants are daffodils, tulips, crocuses, hyacinth and snowdrops. They usually bloom in the spring or summer and have large lush foliage. While most bulbs can live without any care, there are some things you can do to help them thrive.
Water the bulbs right after planting them. This is will help the establish roots, especially if you planted them in the fall. You want them to root before winter comes. Then, during the warmer months, only water them when rain is a shortage.
Allow the foliage to turn yellowish-brown. Don't cut them back while they are still green. The plants are still absorbing sunlight, turning it into sugar (photosynthesis) and storing the sugar in the bulbs for next year's growth. Your plants will be fuller and have more blooms in subsequent years if leave the greens on.
Mulch over hardy bulbs during the winter in areas that have cold weather. This will insulate the bulbs and keep them warm. Most spring blooming bulbs (e.g. daffodils, tulips) are hardy bulbs which means they can withstand cold weather.
Dig up tender bulbs when the leaves start to turn yellowish brown. Store them in a dry, well ventilated and cool (50 to 60 degrees F) location. Place the bulbs in a paper or mesh bag or an open container with a handful of peat moss mixed in so they don't rot. Most summer blooming bulbs (e.g. dahlias) are tender bulbs and need to be stored until the spring when they can be replanted.
Plant your bulbs soon after you get them. If not, you will need to store them until planting season, usually in the fall for hardy bulbs and in the spring for tender bulbs. Store them in the same manner as described in step 4.
Divide your bulbs, approximately every three to four years. If you notice your plants are not blooming as much and are not as full as previous years, they are probably over crowded. Dig up your bulbs carefully and divide them with your hands. The fall is the best time to do this. Then replant hardy bulbs or store the tender bulbs as described above.