TubersAs tubers mature, they increase both their size and the number of growing points. However, most tubers do not form distinct increases. Therefore, to divide tubers, a large tuber should be cut into two or more sections, being sure that each section contains at least one growing point.RhizomesThe new growth on rhizomes is produced from growth points located at their sides. Rhizomes are divided by breaking the sections apart at the natural divisions between them, being sure that each of the new divisions has at least one growth point on it.Tuberous rootsA tuberous root will contain several growing points. Some, like daylilies, form separate and distinct plants, which can simply be pulled apart. This type of sectioning is generally done in fall or summer while the plant is still in its growth stage. Other tuberous root plants, such as dahlias, are more difficult to separate. In order to separate more difficult plants like dahlias, you will need to cut the clumps apart so that each root has a growth bud from which to start. With these types of plants, it is best to separate them in early spring, before planting.
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