Ferns cannot tolerate extremes of weather, so they make ideal houseplants. However, the frilly, feathery, and crinkly fronds of ferns are fussy when it comes to their water requirements. One critical consideration is whether to mist or water your indoor ferns.
Indoor ferns need frequent misting and regular watering because they love moisture and humidity. The soil must be kept evenly moist but not soggy. Misting increases the moisture level in the air, but you can forgo the routine if you use a humidifier to keep the moisture level in the room high.
Maintaining a regular misting and watering schedule without waterlogging the plants or increasing the humidity to stifling levels can be challenging for a newbie plant parent. In this article, I will explain how to mist and water your indoor ferns, when and how often to hydrate them, and how to prevent over-or-under-watering them.
How Often Should You Mist an Indoor Fern?
Ferns are native to the tropical rainforest regions of the world with ample rainfall, where the relative humidity level can be 70% or more.
Many buildings, including some homes, usually have only less than 10% relative humidity without a suitable heating, ventilation, and air conditioning (HVAC) system. However, depending on the construction materials, location, and climate, some homes can have a humidity level of about 90%.
Such extremes are unsuitable for human and plant life. Using a humidifier can regulate the humidity to 30-50%, which is ideal.
Still, you must be careful when using a humidifier. Your indoor ferns may thrive in very high humidity levels, but excess moisture in the air can cause bacterial and mold growth that can harm the health of the inhabitants of the house. Too much humidity also creates uncomfortable living conditions.
Ferns need humidity levels of at least 30-50% to thrive and grow luxuriantly. They may tolerate slightly less humidity but won’t sport a lush growth. The tips of the fronds turn brown and wither in dry air.
If you don’t use a humidifier, you must mist your indoor ferns.
You should mist an indoor fern lightly on days you don’t water the plant. Note that misting only temporarily raises the humidity around your plant, so you may have to mist three or four times a day when it is very dry indoors or when you use a heater in winter.
You should mist early in the day to let the water dry and prevent mold and fungus attacks.
Fern Misting 101
Frequent misting makes your indoor ferns grow lush and verdant. However, misting must be done right and promptly to provide these benefits.
Here are the most critical considerations to keep in mind when misting your ferns:
Use water at room temperature (around 68 °F or 20 °C) to mist your indoor ferns. Misting your fern with cold water can send the plants into shock, causing them to develop cold spots on their leaves.
Extent of Misting
Mist lightly ferns with crinkled leaves that don’t dry out quickly and can breed fungus. You can liberally mist broadleaf ferns and those with simple leaf structures.
Inspect your ferns for signs of dehydration. Dried and dead patches throughout the plant and brown discoloration at the end of their leaves are distress signals that indicate your ferns must be misted.
Adjust your misting schedule depending on the fern variety. Ferns like the Boston fern, staghorn, and maidenhair fern need to be misted more often than other ferns like holly ferns.
Keeping Humidity High
If you are not home for long periods during the day and cannot mist your plants often, you can keep the humidity levels high with the following measures:
- Place the pot containing the fern on a tray of pebbles or clay granules and keep these moist.
- Move your ferns to a bathroom used often. This area is probably the most humid place in your home.
- Move your ferns to the kitchen, another area that’s usually more humid than other parts of your home.
- Keep your ferns in an area not exposed to dry air, drafts, or extreme temperatures.
- Consider setting up a humidifier near the ferns.
How Do You Water an Indoor Fern?
Experienced plant parents agree that watering a fern can be a tricky task. Most ferns love moist soil, but almost all hate waterlogged conditions. Using the right watering approach can help you strike the perfect balance and avoid over-or-under-watering.
You should water an indoor fern to soak the soil thoroughly. Pour water on the soil at the base of the plant and above its roots until it flows out of the drainage holes at the bottom of the container. The soil should be kept moist at all times but not soggy.
The most important thing to remember when watering your indoor ferns is to water only at the base of the plant and never from above. When you water the soil at the base of the plant just above its roots, the water permeates the soil and reaches the roots easily. Keeping the plant’s root zone hydrated means the plants can readily absorb moisture.
If you pour water from above, water droplets can splash on the leaves. Ferns can absorb water only through their roots, so the water droplets on the leaves are useless to the plants.
How quickly the water on the foliage evaporates depends on the ambient humidity level. If the water stays there long enough, your plants will attract fungus and mold and develop root rot disease.
How to Water Your Ferns
The following tips will help you keep your indoor fern well hydrated without killing it with too much or too little water:
- Add coco peat or sphagnum moss to the soil to enhance its water-retaining capacities.
- Use a well-draining potting mix that will prevent the roots from becoming waterlogged.
- Only use tepid water.
- Do not let a fern sit in water unless it is a bog fern.
- Water your ferns with soft water because some, like the rabbit’s foot fern, are vulnerable to salinity in the water or the soil.
- Ensure that the containers the plants are planted in contain drainage holes at the bottom.
- Do not let the soil dry out completely between watering.
- Water your ferns more frequently if the temperature exceeds 75 °F (24 °C) because a plant loses water through evaporation from the soil.
- Cut down on watering if the temperature is less than 60 °F (15.6 °C) because the plant does not use too much water when it is very cold.
Not all ferns need the soil to be consistently moist. With varieties like rabbit’s foot ferns, holly ferns, and brake ferns, you can let the soil dry out slightly before watering. Poke your finger in the soil to check for moisture, and water only when the top 2 inches (5 cm) feel dry.
Signs of Over- and Under-Watering
I recommend you learn about the signs of over-and under-watering so you can tweak your watering schedule accordingly.
Here are a few pointers:
- Overwatering causes the leaves to turn yellow and wilt and increases the chances of your plant developing root diseases or fungal growth.
- Underwatering can cause ferns to wilt and drop leaves.
Both over-and under-watering can cause ferns to wilt, so confirm the exact cause by checking the moisture in the soil.
For instance, yellowing leaves and stunted growth in ferns can be signs of magnesium and sulfur deficiency. If you are sure these symptoms have not been caused by over-or under-watering, you can feed Epsom salt to your ferns to replenish these minerals. Thoroughly mix two tablespoons of Epsom salt with a gallon (3.8 l) of water, and water your ferns with this solution.
Keep Ferns Hydrated With Minimal Watering
It can be a chore to keep your ferns hydrated and the soil consistently moist in arid and hot weather. Carrying pails or cans of water to and fro can feel tedious.
To help you out, I have rounded up some nifty ideas for keeping ferns hydrated without needing to water as much:
- Large, water-hungry ferns like the Boston fern can be watered by immersing the container in a bucket of water and letting it sit for half an hour about twice a week.
- You can place the containers outdoors in gentle rain if the temperature exceeds 50 °F (10 °C).
- To thoroughly soak the fiber in which they grow. Staghorn ferns hanging from a basket can be immersed in water every 5-7 days until no bubbles rise.
Use a Second Pot
You can also use a second pot to keep your ferns well-hydrated.
- Find a plastic container that is the same size or larger than the container holding the fern.
- Place the plastic container underneath the pot containing your fern plant.
- Fill the bottom container with sphagnum moss so that the moss lines the outside of the pot containing the fern.
- Keep the sphagnum moss moist at all times. Sphagnum moss retains moisture and supplies it to your fern when it needs it.
- Ensure that the container holding the fern is made of clay, a porous material that lets the plant absorb moisture from the moss.
Keep your indoor ferns well hydrated to enjoy their luxuriant beauty.
Here’s a recap of what you must do when planning an optimum misting and watering schedule:
- Mist your ferns lightly.
- Mist them every few days or multiple times during the day, depending on the ambient humidity.
- Use water at room temperature for misting.
- Keep the soil evenly moist but not saturated.
- Water ferns at the base of the plants just above their roots and NOT from above.
- Look for signs of overwatering and underwatering and tweak your watering schedule accordingly.