Your plant has probably been putting out new leaves for a while now. But at some point, you notice they’re not opening as they should.
Plant leaves may not unfurl for a number of reasons. Low humidity, inadequate sunlight, over-fertilizing, or pest infestation can cause your plants to remain closed and stuck. Plant leaves generally take 1-2 weeks to open, and addressing environmental abnormalities can cause the leaves to open faster.
In this article, we will be sharing all you need to know about why some plant leaves do not open or unfurl and how you can fix these problems.
What It Means When Leaves Do Not Unfurl or Open
When leaves do not unfurl or open, it means that the younger leaves remain closed for longer than they should because of unfavorable internal environmental conditions that would cause harm to the entire plant if the leaves are to open.
Leaves are in a state of preservation where the plant is trying to prevent moisture loss to the environment.
See our detailed article on why already matured plant leaves curl.
When leaves do not bloom open is like the plant is in survival mode, so something has to be addressed to fix the problem, which we will explain next.
What Causes Plant Leaves To Stay Closed?
If your plant leaves are not unfurling even after you have waited for more than enough period, try to check out whether there are any of the cases mentioned below.
Factors that support the closed state of leaves are:
Low Humidity
The lack of humidity is the main reason for the closed state of plant leaves. It speeds up transpiration. It often leads to brown spotting on leaf edges.
Low humidity conditions increase water loss causing the leaves to furl as a mechanism to retain moisture. The stomatal openings in such cases will remain close to retain as much moisture as possible.
Inadequate Sunlight
It doesn’t allow plants to conduct photosynthesis which is a must for their healthy growth. In this condition, plants don’t get enough energy required for unfurling leaves.
To add to the problem, unopened leaves will not be able to receive enough sunlight as they are not positioned for such tasks and will depend on the leaves of the plant to do so.
As a result, leaves turn yellow and fall untimely. Direct sunlight can fix this.
Lack of Nutrients and Over-Fertilizing
Your plant leaves are not unfurling, maybe because the soil lacks a proper amount of nutrients. Nutrient deficiency also causes a change in the color of the leaves.
To meet the requirement, if you over-fertilize, it might cause chemical build-up and hinder water absorption. Consequently, plant leaves will close again.
Extreme temperature
Severely cold temperatures make the plant leaves curl up and remain closed. At the same time, inordinately hot temperatures speed up the process of transpiration, leading to the plant leaves not unfurled.
Nyctinasty
Nyctinasty is the circadian rhythmic nastic movement of leguminous plants in response to the onset of darkness.
Pollinator plants close their leaves at night, showing this behavior which helps to protect their pollen from unwanted pollinators. It also allows the water retained by leaves to trickle down to the roots.
Again, when turgor pressure and the concentration of chloride and potassium change, plants like Mimosa close their leaves when touched.
Too Much Wind
Wind helps the plants accelerate the evaporation rate, and where it is too much, it can cause the rate of evaporation to increase beyond the point the plants can handle the rate at which water is lost.
As a result, the plant will keep new leaves closed to ensure that as much water as possible is retained within the plant.
Will Unfurling Affect Plants?
If you leave your plant leaves to get unfurled naturally, it might not always work. Generally, it takes a lot of time, and sometimes, mostly in winter, leaves get aborted by plants.
Under such circumstances, you might be provoked by some Youtube videos to unfurl your leaves manually.
You can use a sterilized scalpel, a damp cue-tip, or even your finger to gently help the new leaf break free from its sack called Cataphyll.
But, this manual unfurling does no good to the plant. It results in wrinkled plant leaves. Sometimes, it doesn’t interfere with the growth of the plants, and plants keep growing at their own pace.
Again, sometimes this procedure damages the delicate plant by stunting its growth. It might leave some brown spots as well.
Moreover, if your plant leaves get split or torn while unfurling, you might have the only option of cutting them off to help new leaves sprout out, as the damaged ones can be healed by no means.
Plants that have Furled Leaves and the Time it Takes to Open
Different plants take different lengths to unfurl leaves. Now, getting impatient, you might go to the extent of unfurling the leaves of your plants on your own. So, here’s a list of plants that are reactive to physical unfurling.
Monstera deliciosa
It can take anywhere from 1-7 weeks for your monstera houseplant to fully unfurl. By providing the perfect environment and care, the new leaf may unfurl quicker, like under a week, depending on how old it is and what kind of monstera plant it is.
Syngonium
Syngonium leaves can take up to 1 month to unfurl, the longer period may be due to unintentional stress on the plant.
Calathea
Calathea (Prayer plants) can take from 2 to 5 days for the leaves to open up if there are more shoots or plants within the same pot. They will compete for space and nutrients, and some leaves will take longer to open.
Dieffenbachia
Just like calathea, Dieffenbachia leaves can take up to 5 days to open.
Philodendron
It can take a Philodendron leaf anywhere from a few days to a few weeks to unfurl.
Bird of Paradise
Unopened birds of paradise leaves can take as little as one hour up to several days to unfurl, depending on the intensity of the problem making the leaves not open.
Gloriosum
Philodendron gloriosum is a rather slow grower. A leaf spike to a full opening may take 1-2 months.
Pink Princess
Just like calathea, Pink Princess leaves can take up to 5 days to open.
What Can You Do To Encourage Leaves to Unfurl?
To help fix unfurling leaves, you must follow a few necessary steps.
- Keep up 50-70% of humidity around your plant. You can mist them with water every other day or once a week to help them unfurl on their own. You can also refer to the usage of a humidifier in your place.
- Ensure that your plant receives substantial sunlight daily to attain the energy needed for unfurling. Never make the mistake of leaving them in a dark corner. Let them receive 5-8 hours of indirect sunlight.
- Don’t let your plants be thirsty. Use sufficient water. Don’t wet the soil; moisten it instead. Water plants once every week only when the upper surface of the earth Is running bone dry.
Check the humidity level by digging your finger into the soil. Keep pouring water until it runs off the pores at the bottom of the pot.
- Save your plants from heat stress. It causes evaporation leading to the plant leaves remaining closed or not unfurled.
- Provide plants with enough nutrients twice a year. Ensure that it is rich in potassium, nitrogen, manganese, etc., which are extremely necessary for plant growth.
- The quality of water matters. Filter the tap water with a high concentration of salts which thwart water absorption.
How do you fix a Stuck Leaf?
As mentioned above, manually opening the leaves can cause more harm than good. Usually, younger leaves are the ones that remain curled and folded.
These leaves are soft and very fragile, and very small forces can cause them to tear or rip. This will not be favorable for the plant as the plant will know when the conditions and time are right to open the leaves.
Torn leaves will start to turn brown at the tear or exposed parts and will take away from the beauty of the plant.
How Long Does It Take For Leaves To Open
Generally, when plants produce new leaves, from when the leaf emerges to when it opens can take between 2 to 5 days in some plants and up to 4 weeks in others; it all depends on the plant and the conditions they are subjected to.
Environmental conditions can, however, be altered to help the new leaves to open much faster than if they were left alone.
Do Plant Leaves Curl Close After Opening?
The newly unfurled leaves are so lovely, no?
But, sometimes, they tend to curl up. Indeed, there are compelling reasons behind it.
On the one hand, to help plant leaves unfurl, you leave your plant in direct sunlight for 8 hours. The heat stress of this excessive sunlight causes quick vapourization. So, the plant leaves cannot help but choose to curl up to preserve moisture.
On the other hand, to speed up unfurling, as you water your plant thoroughly and sometimes even overly, your plant roots cannot access nutrients and oxygen from the soil. So, the leaves curl up.
The Takeaway:
When a plant is not opening or unfurling its leaves, it can be caused by insufficient water, humidity, and sunlight. A plant needs water and sunlight in order to open its leaves. The amount of water and sunlight that a plant needs depends on the type of plant.
If you start to notice that your plant is staying open at night but closing during the day, this means that your plant is getting too much sunlight. Some plants will close their leaves in direct sunlight to prevent overheating and drying out.
As long as your plant has enough water, humidity, and sunlight, it should be able to open its leaves naturally over time.
