According to the University of Illinois Extension, "a bulb is a promise of a plant to come." A plant bulb is basically a complex system of roots and plant parts that are packed tightly together. In fact, the bulb actually contains a miniature plant, which emerges as it is nourished. The bulb even contains flower stems and leaves, which are packaged in an outer layer called a tunic. Once the bulb has received adequate sun and nutrients, it will emerge from the soil and grow like other plants.

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An onion is an example of a bulb plant.

Calla Lilies

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Calla lilies bloom in a variety of colors.

Calla lilies are popular flower selections for flower bouquets. The tube-shaped flower comes in a variety of colors, including white, yellow and red. Calla lilies grow in a variety of light conditions, including full sun, partial sun and shade in USDA zones 7 through 10. According to Bulb and Bloom, they grow in large numbers on America's West Coast, along the ocean cliffs. They are deer-resistant and bloom in late spring.

Anemone

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Anemone flowers resemble poppies.

Anemone plants have thin flowers that can be white, blue, purple, red and pink. They thrive grow well in full or partial sun in USDA zones 5 through 9. Anemones are native to the Mediterranean, and do well in flower beds as well containers. They tolerate drought and very easy to grow. Anemones bloom in early to mid-spring.

Camassia

Camassia's delicate purple, white or blue flowers are attractive and the plants are easy to maintain. They grow well in full and partial sun in USDA zones 3 through 10. Camassia is native to North America and tolerates clay or wet soil conditions. According to Better Homes and Gardens, "Camassia is a perfect flower for extendng the spring bulb season."