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Fern Not Growing? (Here’s How To Fix It)

If you have a problem with ferns and don’t know how to solve it, this article is for you.

The most common reasons for ferns not growing are root rot, too dry air, underwatering, or improper lighting. To revive a fern, water it no sooner than the soil is 1 inch dry on top and provide the plant with at least 65% humidity. Also, make sure the fern gets 6 hours of indirect but bright sunlight a day.

Root rot is the most common cause of a fern not growing

A fern can suffer from overwatering even though it is a moisture-loving plant. In nature, the fern grows under large trees and excess water is quickly absorbed by the roots of these trees. Accordingly, the roots of the fern are always in a moist but not wet medium.

If you have not been able to recreate the native conditions for this plant, problems may arise. Root rot is most often the result of too much watering or if there are no bottom holes in the pot. Also often the soil may be too clayey and damp, or you may leave water in the drip saucer after watering.

If root rot affects your fern, the lower fronds will begin to turn yellow. The rest will begin to turn brown at the tips and droop. The roots in the pot will be mushy and foul-smelling. Overall, the plant will be weak and stop growing.

Fern not growing

Fern not growing due to root rot.

Solution:

  • Gently pull the fern out of the pot and inspect the roots.
  • If the roots show rot, remove it and then wash everything down with an aqueous hydrogen peroxide solution (1:5).
  • Dry the roots a little and remove any severely damaged fronds.
  • Plant the fern in sterile and well-drained soil from a reliable manufacturer. Use pots with at least 4 drainage holes that are at least a quarter-inch in diameter.
  • Water the fern only when the soil is 1-2 inches dry.
  • During the winter months, allow the soil to dry 2-3 inches.
  • Avoid frequent watering schedules and never leave water in a saucer under the pot.

Too dry air

The next reason why the fern may not grow is insufficient humidity. It is common knowledge that this plant grows under trees where, in addition to shade, there is also high humidity in the air. But in the house, such humidity is difficult to achieve, and as a result, ferns can feel uncomfortable.

Symptoms of insufficient humidity are brown curled leaf tips or brown fronds. Sooner or later, the leaves will begin to fall off and the plant will noticeably stunt its growth. Very often the dry and hot air from the heater can damage fern leaves. Therefore, avoid placing this plant near heaters and other devices that produce heat.

A humidity of 60-70% is most comfortable for ferns. But it’s not always possible to provide such conditions, so if you get to 50% humidity it’s already suitable, the main thing is to keep it no lower.

Solution:

  • Install an air humidity meter (hygrometer) near the plant to monitor the humidity regularly.
  • To increase the humidity, place a tray near the fern that is half-filled with pebbles and a third with water. Such a simple device will evaporate some water and increase the humidity.
  • Or place all your plants next to each other and the moisture will stay near them longer.
  • The last effective method is to install a humidifier.
  • Avoid misting the leaves as well as placing ferns in the bathroom, as this will lead to fungal diseases.
  • Provide good air movement around the plant.

Dehydration

Underwatering, as well as overwatering, can cause the fern to stop growing. I have already mentioned that it is a water-loving plant and needs constantly moist soil. If the soil dries out completely, the plant can be severely damaged.

Underwatering causes the fronds to turn brown starting from the tips. The leaflets will also turn brown and begin to wilt. Another obvious symptom is very dry potting soil.

If the soil has been dry for a short period, the plant will survive and begin to grow after watering. But if you don’t water a fern for a long time, it can die.

Solution:

  • Install a soil moisture meter. This will allow you to quickly and precisely determine when to water.
  • If the soil is 1 to 2 inches dry, water the fern. Use plenty of water, the rest should come out through the drainage holes.
  • If the soil dries out too quickly (sandy soil), transplant the fern into a more water-holding soil. Use lots of organic matter to get a good soil mix.
  • Avoid surface watering and watering on a schedule.

Inadequate lighting

Incorrect lighting can also cause a fern not to grow. First of all, it is a matter of inadequate light. The fern likes to grow in the shade of large trees, but still through the canopy passes a lot of bright and diffused sunlight. So if the plant is growing in a northern room, for example, it will feel the deficit of light.

Symptoms of light deprivation are the exhaustion of the plant. The fronds will become softer and droop slightly. The leaflets will also become saggier and the color will change to light green. The plant will grow slowly and stretch out due to the lack of UV light for photosynthesis.

On the other hand, direct sunlight can do a lot of damage to the fern. If it receives direct sun in the middle of the day, the leaves will permanently burn (turn brown) and shrivel. The plant will not develop normally and its growth will stop.

Fern not growing

Direct sun

Solution:

  • Place the fern in the east room where it will get 3-4 hours of direct morning sun and the rest of the time in the shade with bright indirect sunlight.
  • In a southern room, the fern should be in the back of the room or to the side of the window without access to direct sun. The same applies to the west room.
  • Avoid placing the fern in a northern room, but if there is no choice, install artificial light.
  • When changing sun exposure, do so gradually.

Too many nutrients

Very often when trying to help our plant, we can easily harm it. This sometimes happens when growing a fern. Fertilizing it frequently can have a negative result because over-fertilization can burn the roots.

If you fertilize your fern more than once a month brown spots can appear on the leaves. The plant will grow vigorously at first, but then it will be depleted and growth will slow down or stop altogether.

On the other hand, a lack of nutrients can also cause a slow growth of a fern. This is especially true when growing ferns in pots. When it is not growing in a pot it can get its own nutrients, but in a pot, it is totally dependent on the host.

Fern not growing

Overfertilization

Solution:

  • If you have fertilized the fern too often you need to flush out the excess fertilizer with water. Take the plant outside or put it in a bathtub and water it for a few minutes with plenty of water.
  • Another way to correct over-fertilization is to transplant the fern into fresh soil.
  • Do not fertilize the fern for several months afterward.
  • Thereafter, fertilize the fern no more often than once every 2-3 months with a liquid multipurpose fertilizer. Or use slow-release pellets once a year.
  • Avoid fertilizing the fern for the winter.

Pests

The last possible reason for the lack of fern growth is pests. In the first place, this concerns the spider mite. Dry indoor air is an ideal environment for these insects because they do not like moisture. They are very small and difficult to see, but they wrap a fine cobweb around the leaves.

Spider mites usually spread on the underside of leaves. They feed on the sap of the fern, which causes the leaflets to turn yellow. The plant as a whole grows slowly.

The second type of pest is the mealybug. These insects also feed on the sap of the plant and stop its growth. The mealybug is easy to spot because it leaves behind white flour-like traces.

Fern not growing

Mealybugs

Solution:

  • Take a good look at the plant. Use a magnifying glass to detect spider mites.
  • An aqueous solution of neem oil or other horticultural oil works well against mealybugs. In rare cases, pesticides should be used.
  • To get rid of spider mites, raise the humidity to at least 60% and spray the fern with acaricide.