How to Divide Bulbs: Techniques for Five Bulb Types

Sparse blooms signal overcrowding—time to dig and divide. Also divide to propagate favorites. Each bulb type increases differently, so techniques vary.

• True bulbs: Break apart parent and offsets at base. For lilies (Lilium), remove outer scales from basal plate, dip in rooting hormone, plant.
• Corms: Renew annually with new corm + cormels atop old corm. Separate healthy new corms and cormels from old.
• Tubers: Enlarge and add growing points but rarely form separate offsets. Cut large tuber into sections, each with a growing point.
• Rhizomes: Produce new plants from side growth points. Break apart at natural divisions; each piece needs ≥1 growing point.
• Tuberous roots: Multiple growing points. Daylilies (Hemerocallis) form separable plants—pull apart in summer/fall when growing. Dahlias don't separate easily; cut clumps so each root has a growth bud; do in early spring before planting.