The Snake’s Head Fritillary (also known as the Checkered Lily) is one of my favorite early spring bloomers. To make sure those iconic bell-shaped flowers pop up on schedule, the plant spends the winter tucked away as a bulb underground. But if you’re wondering just how much a “deep freeze” these little guys can handle, here’s the scoop.
Winter Hardiness
The early-blooming Snake’s Head Fritillary (*Fritillaria meleagris*) is actually incredibly hardy. When planted in the ground, it can withstand temperatures as low as -22°F (-30°C). However, there’s a catch: that ruggedness only applies to bulbs in the garden. If you’re growing them in pots or containers, they’re going to need a little extra TLC to make it through the winter.
Bulbs in the Garden
Even though these bulbs are tough enough to survive most winters without help, I always like to play it safe. You can give your planting spot a little extra protection by mulching with:
- Dried leaves
- Evergreen brush/twigs
- A layer of humus
While they handle the cold well, there’s a hidden danger: “black frost” (or bare frost). This happens when it’s freezing cold but there’s no snow cover to act as insulation or a moisture source. In these conditions, the bulb can’t pull water from the frozen ground and might actually dry out. If you hit a long, dry cold snap without snow, give your bulbs a tiny bit of cold water to keep them hydrated.
Overwintering on the Balcony or Patio
If you’re keeping your Checkered Lilies in pots on a balcony, they lose a bit of that natural “ground insulation.” Since the frost can attack the bulb from all sides through the container walls, your potted Fritillaria needs a winter coat:
- Wrap the sides of the pot in burlap, bubble wrap, or specialized garden fleece.
- Block the cold from below by placing the pot on a thick wooden board or a sheet of Styrofoam.
- Protect the top by covering the soil with some evergreen branches.
Don’t forget to check on their water levels! Potted plants dry out much faster than the ground does. To keep the bulb from shriveling up, give it a small drink:
- Every once in a while
- Using cold water
- Only on days when the temperature is above freezing
One pro tip: Avoid using warm water. It might seem like a nice treat, but it can actually trick the bulb into thinking spring has arrived early, causing it to sprout way too soon!
