Understanding Potted Ferns' Thirst: Daily Watering Needs In Hot Weather

Potted ferns require careful attention to watering, especially in hot weather. Their natural habitat is the rainforest, so they are accustomed to abundant rainfall and humidity. To keep your fern healthy, it's important to provide consistent moisture to the root zone and maintain a good level of humidity.

In hot weather, ferns will need to be watered more often. Aim to water in the morning to protect your fern from heat stress throughout the day. It's also a good idea to mist the foliage for added moisture on hot days.

The best way to determine if your potted fern needs water is to check the soil. If the surface of the soil feels dry, it's time to water it. For potted ferns, the weight of the pot is a good indication—if it feels lightweight, the soil is likely dry. However, be careful not to overwater, as this can lead to root rot and other fungal diseases.

Ferns need a lot of water, but not too much

Ferns are lush, hardy plants that invigorate our homes and gardens with their airy, billowing foliage or dense, bushy fronds. They are surprisingly easy to care for and grow, but they do have specific water requirements.

Ferns are tropical plants that thrive in moist soil and humid climates. They typically require heavy watering, regardless of the variety, as they originate from the tropics, where rainfall is ample and frequent, and humidity makes the air damp.

The key to watering ferns is to keep their soil consistently moist, but not waterlogged. Aim to keep the top few inches of soil moist, and water when the surface of the soil feels even slightly dry. You can also assess the moisture level by lifting the pot—if it feels lightweight, the soil is likely too dry.

In hot weather, ferns will need to be watered more frequently, as the increased temperature will cause more water to be lost to evaporation. Depending on the heat, potted ferns may need to be watered daily.

How to Water Ferns

When watering ferns, it is best to avoid watering from above, as this can cause moisture to splash onto the leaves. Instead, direct the water towards the soil above the roots, allowing it to trickle down into the root zone, where ferns can absorb it.

Water the ferns until the water seeps through the drainage holes of the pot, ensuring that the water reaches the roots. It is important to allow excess water to drain out of the pot to prevent water accumulation or stagnation in the root zone, which can lead to root rot.

Tips for Retaining Moisture

Potted ferns in wooden, woven, or clay containers will need less frequent watering compared to those in plastic containers, as porous materials promote moisture and air movement throughout the soil.

To retain moisture between waterings, you can add a thick layer of mulch beneath ferns planted outdoors, using materials such as pine bark, pine needles, or coarse compost.

Signs of Overwatering and Underwatering

Both overwatering and underwatering can lead to wilting, but you can differentiate between the two by checking the moisture level of the soil. If the soil is moist and the plant is still wilting, it is likely due to overwatering.

Overwatering can cause yellowed foliage, wilting, root problems, and fungal diseases. On the other hand, underwatering will cause wilting and reduced growth, and the Boston fern is especially prone to dropping leaves when it doesn't get enough water.

Creating the Right Environment

To create an environment that mimics the tropics, you can group plants together to create a microclimate or use a humidifier. Misting the foliage of the fern with room temperature or lukewarm water is another way to increase humidity and replicate the fern's natural habitat.

Water Quality

It is best to use filtered or distilled water for your ferns, as tap water contains chloride, fluoride, and other salts that can be harmful to the plants. If distilled water is not accessible, you can fill a container with tap water and let it sit overnight, allowing the salts and minerals to settle, and then use the clearer water from the top.

Watering frequency depends on the soil type

The watering requirements of potted ferns vary depending on the type of soil they are planted in. While most ferns prefer moist and well-drained soil, the specific soil type and composition will impact how frequently you need to water them.

For example, if you use a soil mix that includes fine peat, potting soil, and perlite, you may need to add extra perlite if the plant is in a low-airflow location to improve drainage and prevent overwatering. On the other hand, if you use a soil mix with more perlite and fine bark chips, you might water this mix less frequently as it provides better drainage.

The type of pot or container you use can also affect watering frequency. Hanging baskets and pots can dry out quickly, so you may need to water them more often to maintain damp soil. Additionally, the outdoor temperature can impact how often you need to water your ferns. In hot weather, the soil will dry out faster, and you will need to water your ferns more frequently to keep the soil moist.

When determining how much water your potted ferns need, it is crucial to consider the specific soil type and mix, the type of container, and the environmental conditions, such as temperature and humidity. By taking these factors into account, you can adjust your watering schedule to ensure your ferns receive the appropriate amount of water without overwatering or underwatering them.

Soil should be moist, but not wet

When it comes to potted ferns, the key to healthy plants is to keep the soil consistently and evenly moist—but not wet. This can be tricky to get right, especially in hot weather when the soil dries out more quickly. So, how can you tell if your fern's soil is just right?

Firstly, it's important to get to know your soil type. Some soils are naturally lighter in colour, so they may appear dry even when they're not. Familiarise yourself with how your specific type of soil typically looks and feels when it's moist and dry. As a general rule, dry soil is often light-coloured, compacted, and crumbly, while moist soil is darker, muddy, and able to hold its shape.

To check the moisture level of your fern's soil, you can use one of the following methods:

• Visual inspection: Simply look at the soil. If it appears dry on the surface, it's probably time to water your fern. However, this method is less reliable for drought-tolerant plants like cacti and succulents, as they only need to be watered when the top inch or so of soil is dry.
• Finger test: Stick your finger 2-3 inches (about 5-8 cm) into the soil. If it feels dry or the soil falls off your finger, the plant needs water. Be careful not to damage the roots.
• Lift the pot: Pick up the pot to check its weight. If it feels lighter than usual, it's probably because the soil is dry and needs water. Water adds weight to the pot, so a lighter pot usually indicates dry soil.
• Moisture sensor: Insert a moisture sensor probe about 3/4 of the way into the soil. Most sensors will indicate moisture levels with colours or numbers. If using a numbered probe, a reading below 5 means the soil is dry, while a reading above 5 means it's moist.
• Gravimetric method: This scientific method involves weighing a sample of your soil, drying it out in an oven, and then weighing it again. The difference in weight will tell you how much moisture is in the soil.

Remember, the goal is to keep your fern's soil consistently moist, but not waterlogged. Water your fern when the surface of the soil appears dry, or when a finger test or moisture sensor indicates that the soil is dry. Allow the soil to dry out slightly between waterings, but not completely. With regular attention and care, your potted ferns will thrive even in hot weather.

Potted ferns in wooden, woven or clay containers need less water

Therefore, if you have a potted fern in a wooden, woven or clay container, you won't need to water it as frequently. However, it's still important to ensure that the soil stays damp, as ferns flourish when they have access to a consistent and plentiful supply of water. You should also take into account the temperature and humidity of your environment when deciding how much to water your fern. If temperatures climb above 75°F (24°C), your fern will need more water, as higher temperatures cause increased evaporation. Similarly, if the humidity is low, you may need to water your fern more often to compensate.

To check whether your potted fern needs watering, inspect the soil. If the surface of the soil is dry, it's time to water your fern again. You can also touch the soil to be sure—if it feels dry, it's time to water. However, be careful not to overwater your fern, as this can lead to root rot. Allow the soil to be damp or slightly dry before watering again.

If you're having trouble keeping your fern well-hydrated, you could try double-potting it. Place your fern into a larger, decorative container and use peat or sphagnum moss to line between the two planters. Keep the moss moist, and this will help to keep your fern happy and healthy.

Mist the fronds daily to increase humidity

Ferns are tropical plants that thrive in high humidity. In their natural habitat, they benefit from frequent rainfall and damp air. To replicate this environment, you can mist your ferns daily, preferably in the morning, to increase the humidity around the plant. This is especially important if your fern is showing signs of low humidity, such as brown discolouration at the ends of its leaves.

Misting the fronds of your fern imitates the conditions of the tropics, where these plants originate. Aim to mist the foliage with room-temperature water once or twice a day. Alternatively, you can place a humidifier in the room to increase the humidity for all your ferns. This is a good option if you have multiple ferns, as misting each one daily can be time-consuming.

If you choose to mist your ferns, it is important to use room-temperature water. Misting with cold water can cause spots on the leaves. Additionally, avoid watering from above, as this can cause moisture to splash onto the leaves. Instead, aim the water at the soil above the roots, allowing it to trickle down into the root zone where the fern can absorb it.

By providing a consistent level of moisture and mimicking the humid environment of the tropics, you can help your ferns thrive and boost their health.

Frequently asked questions