According to Clemson University Extension, "the term "bulb" is commonly used to refer to true bulbs and other bulb-like structures such as corms, tubers, tuberous roots and stems, and rhizomes. Bulb-like structures store food to ensure the plant's survival during unfavorable cold or drought conditions. Grown in a wide range of shapes, colors and sizes, bulbs are ideal planted in flowerbeds and gardens, along walkways, or grown within containers.
Grape hyacinth (Muscari armeniacum) is a spring-blooming perennial bulb that grows best in USDA zones 4 to 9. Low growing, it grows just under 1 inch long, an ideal spring bulb to grow along the front of a flower bed or border or grow in masses as a ground cover to the garden. The fragrant, sky blue to lavender, white-striped tightly packed, urn-shaped bells on grape hyacinths make up the upright, conical raceme. Each small raceme on grape hyacinth holds 20 to 30 scapes or small flowers that make up the grape-like flower. The green, fleshy, 12-inch-long basal leaves on the grape hyacinth are narrow and grow in floppy clumps along the base of each plant. Grape hyacinth grows best in full sun to part shade and well-drained soil.
Ornamental onion (Allium senescens) is a perennial bulb that grows best in USDA zones 4 to 10. It grows 6 to 12 inches tall and wide and has a clumping growth rate. The fragrant, long-lasting, 12- to 40-inch-long, pink to lilac puffball-like flowers on ornamental onions grow in clusters of 30 and attract butterflies and hummingbirds to the garden. The narrow, strap-like leaves on the ornamental onion have a tendency to twist, creating an interesting look to this summer-blooming bulb. Ornamental onions grow best in full sun to part shade and well-drained soil. They tolerate most soil varieties, creating a versatile bulb.
Peruvian daffodil (Hymenocallis narcissiflora) is an early-summer blooming perennial bulb that grows in USDA zones 9 to 11. It grows 1 to 3 feet tall and has a spread of 6 to 12 inches wide, and it is ideal grown within a perennial flowerbed. The fragrant, white and yellow petals on Peruvian daffodils curve up to accentuate the daffodil-like cup that often has green stripes. Peruvian daffodils have long, arching dark-green leaves that are strap-shaped, adding unusual texture to the garden. They grow best in part shade and moist, well-drained soil.