Overwintering Calla Lily in Garage (SE Michigan): Only If Frost-Free

Dormant Callas Tolerate Cool, Not Frozen

In SE Michigan (Zone 5b/6a), an unheated garage often drops below freezing—fatal to calla rhizomes.

Safe Garage Storage Conditions

• Garage must stay above 32°F (0°C) all winter.
• If attached to heated house and insulated, it might work.
• Use a min/max thermometer to verify.

Better Alternative: Basement

Cool (40–50°F), dark, dry basement is ideal. Pot up, water minimally (once a month), store 3 months. Bring to sunny window when shoots appear.

If Garage Freezes: Basement Only

Don't gamble. Frozen rhizomes turn to mush. Basement storage is zero-risk.