Tuberose bulbs include plants like iris and begonia. Unlike true bulbs, tuberose bulbs are root sections that store nutrients much as bulbs do but do not have the all the plants parts stored inside like bulbs. Dividing tuberose bulbs or roots requires more attention to detail, or you are left with useless root sections incapable of growing into full plants. Tuberose bulbs are divided in fall after the foliage has begun to die back naturally on the plants.
Cut back the dead and dying foliage to approximately 2 to 3 inches above the soil level. Use sharp shears or a knife and avoid pulling on the foliage, which may damage the bulb.
Dig around the tuberose bulb, taking care not to cut into with your trowel. Slide your trowel under the root system and lift it from the soil.
Brush away excess soil from the bulb. Inspect it for damage or signs of rot, including soft spots. Look for any withered areas that signify disease may be present. Cut off any damaged areas and discard.
Break the tuberose bulb apart with your trowel or use a sharp knife to cut it apart. Cut each section so that it has two to three growing eyes or nodules present on it. These appear similar to the eyes on potatoes but may be more subtle, so look closely.
Replant the bulb to the same depth they were at before. Plant extra tuberose bulb sections in a new bed; give away to other gardeners or discard if they are inferior in size or quality.