Dividing Calla Lilies in Maryland: When and How to Split a Huge Clump

Your calla lilies (Zantedeschia) have thrived for three years in Maryland—one clump has 30+ shoots and is begging for division. Since they overwinter in-ground (you're likely in Zone 7a–7b near the coast), timing and technique matter.

Best Time: Early Fall

Wait until foliage yellows naturally after bloom—typically September to early October in Maryland. This lets the rhizomes store maximum energy before disturbance.

Step-by-Step Division

1. Lift the clump with a garden fork, starting 12 inches out to avoid slicing rhizomes.
2. Shake off soil gently; rinse with a hose if needed to reveal structure.
3. Identify divisions: Look for distinct rhizome segments with visible growing points (eyes) and roots.
4. Break or cut apart at natural joints. Each piece should have at least one eye and a root mass.
5. Cure: Lay divisions in a single layer in a shaded, airy spot for 2–3 days to callous cut surfaces.
6. Store: Pack in dry peat moss, vermiculite, or paper bags in a dark, cool (45–55°F), dry basement until spring.
7. Replant: After last frost (mid-April in MD), plant 3–4 inches deep, 12–18 inches apart.

Pro Tips

• Discard any soft, mushy, or foul-smelling pieces—signs of rot.
• Dust cut surfaces with sulfur or cinnamon (natural fungicide) before curing.
• Label varieties if you have multiple colors.
• Don't divide every year—every 3–4 years is plenty for callas.

Your generosity will be rewarded: more plants, better air flow, and renewed vigor.