Ferns are among the oldest plants on earth, and their delicate fronds bring a calming, timeless beauty indoors.
While most people grow them in soil, did you know you can also grow certain ferns directly in water?
This method, often called hydroculture, not only looks elegant but also cuts down on mess and soil-related pests.
A fern in a glass jar of water can become a living piece of art on your shelf, desk, or windowsill.
Here’s everything you need to know to grow ferns in water and keep them thriving.
Choosing the Right Fern
Not all ferns adapt well to water.
Some, like Boston fern (Nephrolepis exaltata), Maidenhair fern (Adiantum spp.), and Asparagus fern (Asparagus setaceus), can transition nicely from soil to water.
Others, like the naturally aquatic Water Sprite (Ceratopteris thalictroides), are perfectly at home in water from the start.
You should choose a healthy specimen with plenty of green fronds, since weak or stressed plants may struggle during the transition.
Preparing Your Fern
The key to success is starting with clean roots. Remove your fern gently from its pot and shake away loose soil.
Next, rinse the roots under lukewarm water until all soil particles are washed away, any leftover soil can rot and foul the water quickly.
If you notice roots that look mushy, dark, or brittle, trim them off with sterilized scissors.
Healthy roots will be firm, pale, and ready to adapt to their new environment.
Setting Up Ferns in Water
Pick a container that shows off the plant’s beauty while supporting healthy growth.
A clear glass vase, jar, or even a wide bowl works well because you can easily see the roots.
You now fill it with distilled, rain, or filtered water until the roots are fully submerged, but keep the crown, the spot where the fronds meet the roots, above the waterline.
If this crown stays wet, it can rot, which is one of the most common mistakes people make.
Finding the Right Spot
Ferns love gentle, indirect light. A bright room works well, but avoid direct sunlight because the glass can magnify the heat and scorch both fronds and roots.
They’re happiest in rooms with consistent temperatures between 65-75°F (18-24°C).
Bathrooms, kitchens, or any spot with naturally higher humidity are ideal since extra moisture in the air keeps the fronds lush and green.
Caring for Your Water-Grown Fern
The beauty of this method is in its simplicity, but consistency is everything.
You should change the water every 5-7 days to keep it fresh and oxygenated, preventing rot and algae.
If you want to encourage stronger growth, add a couple of drops of diluted liquid houseplant fertilizer once a month, but resist the urge to overfeed as too many nutrients in standing water can burn roots.
In addition, keep an eye on the water level and top it up as needed.
If fronds start looking dry or crispy, move the jar to a more humid spot or group it with other houseplants to create a microclimate.
Benefits of Growing Ferns in Water
Growing ferns in water creates a unique, soil-free display that looks clean and modern. You’ll avoid pests like fungus gnats that often come with potting soil.
Plus, you can easily monitor root health since they’re visible in the jar.
A fern floating in water feels both minimal and lush, making it a perfect conversation starter in your living room or office.
Common Problems and Fixes
If you notice roots turning mushy, it usually means the crown is submerged or the water has gone stagnant, refresh the water and keep the crown dry.
Algae may form in jars left in bright light; if it does, simply clean the container and place it in a slightly shadier spot.
Also, growth in water is often slower than in soil, but don’t worry as your fern can stay vibrant for months, even years, if properly cared for.
