Bulbs are spring or summer flowering. A gardener will find that the bulbs multiply naturally in the soil. After digging the bulbs out of the flower bed or garden, the gardener will separate new bulblets from the root system and mother bulb. Multiply plants such as lilium and narcissus by using the twin-scaling method of bulb multiplication, according to the International Bulb Society.
A bulb houses the nutrients and plant parts within a papery skin-covered teardrop shape. The hardy spring-flowering bulb such as the daffodil and tulip is planted in the fall as it is able to winter over. The more delicate summer bulb, including the amaryllis, is planted in a pot or flower bed in the early spring and dug back up after the plant has finished blossoming.
During summer growth, the new bulb growth or bulblets form from the mother bulb. When the summer bulb plant matures and the system is dug up, the new bulb growth is removed from the root mass. Spring flowering bulblets continue to grow until the plants is removed from the garden for division. The maturing bulblets are separated and replanted in early fall.
Small bulbils or bulblets grow under the papery skin covering on a Red Spider Lily plant during the naturalization process. The mature bulb can produce up to 20 bulbs within five years. Shallots and garlic reproduce in this fashion. The young bulbs may push to the surface of the soil due to overcrowding.
Use a bleach solution to sterilize healthy bulbs three months before planting time. Wash the bleach solution from the bulbs with plain water. Cut one-third of the bulb top away before cutting and separating scales without severing them from the basal plate. Cut two scales off from the bulb with a piece of the basal plate intact. Continue cutting away scales and basal plate sections and place them into a bleach solution for half an hour. After draining and drying the segments thoroughly place in sterilized vermiculite and store in an airtight bag. Store in a dark place, at 20 degrees C until roots and bulbils form.
If spring bulblets are left in the garden bed for more than two years, the main plant will produce smaller flowers as all the energy and nutrition is being focused on bulb growth. Dig up the entire bed of spring flowering plants, remove and separate the bulbs. Work up the flower bed, border or garden and replant the entire mass of bulbs.