Water lettuce originally hails from the warm tropics, so it’s definitely not used to our chilly winters. If you’re keeping these beauties in your garden pond, you’ll need to give them a little extra TLC to get them through the cold months. The best way to do that? Move them into an aquarium!
Water Lettuce Isn’t Winter-Hardy
Let’s be real: water lettuce just can’t handle our freezing temperatures and icy ponds. If you leave them outside, they won’t survive the frost. To make sure they come back in full glory next year, you’ve got to bring them indoors for a proper winter break.
How to Overwinter Your Water Lettuce
Timing is everything! Make sure to scoop your water lettuce out of the pond before the first frost hits. Since they just float right on top, a simple pond net makes it super easy to fish them out.
The Best Winter Homes for Water Lettuce
You’ve got two great options for keeping your plants happy indoors:
- An aquarium
- A large, water-tight container
Overwintering in an Aquarium
An aquarium is actually the perfect winter home for water lettuce. Just keep an eye on these specific needs to keep them thriving:
- Plenty of bright light
- Temperatures between 60°F and 78°F (15–26°C)
- High humidity or direct contact with water
- A pH level between 6.5 and 7.2
Overwintering in a Container
If you don’t have an aquarium, don’t sweat it! A large container or tub works just fine. Fill the bottom with a thick layer of loam or clay-heavy soil and top it with water. Just remember that the same light and temperature rules mentioned above still apply.
Moving Back Outdoors in the Spring
Once the threat of frost has passed, you can move your water lettuce back into the garden pond. This is the perfect time to do a little “spring cleaning.” Thin out any extra runners to keep them from taking over the whole pond, and feel free to trim back those super long roots if they’ve gotten a bit wild.
A Win-Win for Your Aquarium
Here’s a pro tip: overwintering water lettuce in an aquarium isn’t just good for the plant—it’s great for the tank, too! Water lettuce is a natural algae-fighter. While it’s hanging out indoors, it’ll help keep your aquarium water crystal clear by soaking up the nutrients that algae usually feed on.
Care Tips During the Winter
Water lettuce is what we gardeners call a “heavy feeder,” meaning it has a big appetite for nutrients. While it’s spending the winter in your aquarium or container, make sure it stays well-fed. Use a high-quality aquatic plant fertilizer regularly to keep it lush and green until spring.
