Most true bulbs, such as daffodil, tulips and crocuses are planted in the fall so they can become established and grow fleshy roots during the winter months. However, they can be planted in the spring, as early as possible when the ground is workable. Most other bulbs, such as cannas, gladiolus and dahlias, are tender and are not "true" bulbs. They are usually corms, tubers and rhizomes and are planted in the spring when the ground warms up.
Prepare the planting bed by using a garden rake, hoe or tiller to turn over the top 12 to 18 inches of your soil. Then mix in several inches of organic matter, such as peat moss, sand or compost. This will make your garden bed rich in nutrients and more suitable to water drainage.
Dig a trench that is three times as wide as the bulbs. The depth depends on the bulbs. True bulbs like daffodils, crocuses and tulips are typically planted about two times as deep as the bulbs are in height. Corms, tubers and rhizomes are generally planted just under the soil's surface.
Place the bulbs in the trench with the tips--or eyes or necks for other bulb-like structures--facing up. At a minimum, plant the bulbs so that the space in between them is at least twice as wide as the bulbs themselves.
Backfill back the soil over the bulbs and pack it firm so there are no remaining air pockets.
Water well so the water seeps into the soil to reach the bulbs as deep as they were planted. Just sprinkling the surface soil will not be sufficient. After the bulbs begin to emerge, water the bulbs 1 inch of water once a week if rain was scarce.