Most species of plants also need periods of darkness in order to thrive and achieve optimal growth rates. This period of “rest” allows them to process the nutrients from photosynthesis more quickly and easily than if exposed solely to daylight hours. As such, understanding what kind of environmental conditions best suit various types of plants is crucial when cultivating any type of plants indoors or outdoors!
The alternation of light and darkness during a day is called the photoperiod. In addition to inducing plant flowering, photoperiod also affects the elongation of plant flower stems, the formation of roots and leaves, the dormancy of buds, and the shedding of leaves.
However, many people are aware of the importance of light, but most of them do not really know about darkness. Many of my friends also having questions about whether the plants need darkness to grow?
Plants are like human beings. They will need to rest during nighttime. Even though plants won’t need long sleep hours, periods of darkness are required for plants. Plants reduce the photosynthesis process when it is dark. This helps to reduce water evaporation and nutrient loss to grow and survive even in a bad environment.
Can Plants Survive Without Darkness?
Like a salve for a tired plant, the nighttime’s darkness has restorative properties. Giving it a break from the sun’s rays allows it to repair and recharge. Does that imply, therefore, that plants cannot thrive in the light?
Answering this topic requires knowledge of photosynthesis, the mechanism by which plants transform solar energy into chemical energy used by living organisms. During photosynthesis, chloroplasts in a leaf’s cells utilise the energy from sunlight to convert carbon dioxide and water into carbohydrates and oxygen. That is to say, plants can’t grow or thrive since photosynthesis can’t take place if there isn’t enough light.
While light and darkness are certainly factors, studies have also shown that temperature changes during the day have an impact. Examples include how radiation losses from Earth’s surface cause nighttime lows while significant solar heating keeps daytime highs relatively steady.
This indicates that some species are able to compensate for a shortage of photosynthetically active radiation (PAR) during the day by boosting their activity levels at night. Hence, plants require daily exposure to light in order to thrive, but they can grow in either bright or dim conditions.
The growth of plants is inseparable from sunlight, carbon dioxide, and water, all of which are indispensable. Sunlight is also the most critical factor. If there is no light, the entire process of photosynthesis will be incomplete. Therefore, light is more important for most plants compare to darkness. However, darkness is required for plants as well since plants will need to rest as well.
Necessity Of Darkness For Plant Health
Darkness is absolutely essential for plant health. Plants require darkness to undergo a process called photorespiration, which helps them convert light into energy and nutrients. Without this important process, plants would not be able to survive or grow at their maximum potential.
Other than helping with photosynthesis, darkness also helps regulate growth hormones in plants. By going through periods of both light and dark, plants are better equipped to control the production and balance of these hormones that help promote healthy growth.
Darkness can also help protect plants from extreme temperature fluctuations by providing insulation against excess heat or cold. This allows the plant’s cells to remain stable even during drastic changes in weather conditions, ensuring optimal functioning throughout its life cycle.
How Many Hours of Darkness Do Plants Need?
This darkness helps them to rest and prepare for the next cycle of growth, flowering, or fruiting. Different types of plants will need different hours of darkness. It all depends on the plants. Generally, most plants need to be kept in the dark environment for about 8-12 hours a day. Otherwise, plants may not get to rest well, and this will affect their growth.
For example, for orchid species, in the winter and spring seasons, it is necessary to maintain a completely dark environment for 12 hours a day at night so that it is easy for orchids to grow their buds. Otherwise, it will affect the flowering.
Here are three ways this process works:
- Darkness triggers a plant’s production of hormones needed for cell division and growth.
- It also reduces water loss from their leaves via transpiration.
- Lastly, it encourages photosynthesis in some species by allowing them to store energy during the night.
Darkness requirements vary depending on the type of plant being grown. Some need more than 12 hours per day while others may not require any at all. Generally speaking, most plants need between 8 and 10 hours of total darkness per 24 hour period for optimal development.
Therefore, if you use grow light in your house, you cannot turn the light on all the time. You need to turn it off during nighttime so that it won’t affect the recess of the plants.
How Does Darkness Affect Plant Growth?
Let me explain why plants have a problem at night. Plants use sunlight as energy in a process called photosynthesis. They get energy by taking carbon dioxide. They then produce sugars and many other metabolites with the help of sunlight.
At night, there isn’t any sunlight, so that plants will have no energy in the dark. Plants need to store energy in the light to get through in the night. Many plants store energy as starch because starch can give a lot of calories to them.
So on a light day, when plants receive sunlight, they produce starch. In the evening, when the sky turns dark, the plants start to degrade their starch and use it to support their growth and other needs.
The plant will use the starch that it produces and store during the day. It keeps on using the starch until, at the end of the night, all the starch will be completely consumed by the plant.
How does the plant know how it can do this?
The plant knows how long the night will be. The plant can perform in this way is because it has a biological clock like human beings. Our body knows the time of day. For example, we wake up in the morning and start to get sleepy in the late evening.
A plant also has a biological clock, allowing it to know how long the night will be until the next day. By knowing the time, the plant can decide how quickly to use its starch. Other than starch consumption, the plant uses its biological clock for many other things as well.
The biological clock can tell them the time of the year and decide when they’re going to flower. Besides, they also use the clock to tell them when autumn is coming and fall off the plant. They can do this just before the winter comes.
Ways To Create Dark Conditions For Plants
It is important to create dark conditions for your plants. What you can do is you can keep all doors and windows shut at night to prevent light from entering the room and disturbing the darkness plants require. Blackout curtains or shades can help filter out any artificial light that may be present.
It is also advised that you use Mylar film or aluminium foil to create a reflective barrier around your plants. This allows for a good amount of daylight to enter the space during the day without making it too dark. As an added precaution, it’s best to turn off fluorescent lights while they’re not in use, as their high temperatures could be detrimental to your plants.
Since excessive heat can hinder plant growth even without direct sun exposure, it’s important to keep an eye on nighttime temperatures inside your home or greenhouse. The rate at which metabolic processes like photosynthesis and respiration may occur slows down when humidity levels are high. By using some forethought and organisation, you can easily provide your plants with the perfect amount of darkness they require.
Benefits Of Dark Conditions For Plants
Imagine a plant, curled up in its bed of soil and leaves. Its long stems passionately reaching for the sun that has nourished it since birth. But what about those times when darkness is required? As with anything, balance is key – even in the case of photosynthesis and growth.
- Dark conditions can reduce water loss: Plants need sunlight to support their process of photosynthesis but darkness can help them conserve much needed resources such as water. Photosynthesis requires plants to expend energy and use carbon dioxide which makes them thirsty. During dark periods they hold back on this process and retain more moisture.
- Darkness keeps temperatures regulated: Cooler temperatures in the dark help plants survive heat stress and dehydration. Respiration helps plants take nutrients from the air and recycle critical components, including nitrogen, phosphorus, sulfur, oxygen, and others.
- A good environment for flower buds to grow: Photoperiodism is the process by which light-dependent plants need long periods of nighttime (darkness) during their growing season in order to produce flowers or “buds.” Depending on the species, a plant won’t flower until it has been in a certain amount of light or total darkness for a certain amount of time.
Plant Grow Taller in Darkness?
Some people wonder why some plants in the dark grow taller than those plants in the light. They are confused and think those plants need darkness.
Actually, this doesn’t seem right. When a plant is not getting enough sunlight, the leaves are lesser, and its stem may get elongated. They may look weak, fragile, and can easily break at any time.
Even the plants in the dark grow taller than the plants in the light, but this kind of growth is no healthy. It is equivalent to the growth of saplings, and it can be very delicate. If you don’t move the plant to a sunny place in time, it will fall and break because it grows too tall and the stem is too thin to support.
Even though most plants require a certain level of sunlight to survive, their metabolic processes continue in the dark. An example of the process is known as the Calvin Cycle. This process involves carbon that is captured and then converted into stored energy during the day.
Another process is called respiration. This is a process that will combine oxygen and stored food. It then turns into a nutrient for the plant. Due to photosynthesis, plants will generate oxygen during the day and consume oxygen at night.
Due to the internal circadian rhythm, although it is dark, plants can know if dawn comes. It will get itself ready for dawn at the cellular level and then stimulate the chloroplasts by light.
Why Do Plants Take In Oxygen In The Dark?
Plants are unique because they can do both photosynthesis and respiration at the same time. During the day, they use the sun’s energy to make carbs through a process called photosynthesis. At the same time, they take in oxygen for breathing and give off carbon dioxide as a byproduct of this process. But what happens when it gets dark and there is no light?
In darkness, plants continue taking in oxygen for respiration but cannot perform photosynthesis. They also cannot make their own food since there is no light available for them to do so. The following are some of the reasons why plants take in oxygen during the dark:
- Photosynthesis ceases, allowing respiration to dominate.
- Plant cells need energy to carry out metabolic activities such as growth and repair processes.
- Plants must replenish their supply of oxygen after they consume it during daylight hours while performing photosynthesis.
- Respiration helps remove excess water vapor from plant leaves which prevents dehydration and wilting due to transpiration rates being higher than water uptake at night-time temperatures.
Plants need both light and darkness for optimal growth and development, which means that having both in balance is key for successful cultivation of crops or ornamental flowers and foliage indoors or outdoors all year round. With adequate amounts of both light and darkness combined with proper soil nutrition, environmental conditions, moisture levels, ventilation etc., can play an important role in plant health and vigor over extended periods of time.
The Importance Of Darkness And Light Together
In terms of environmental conditions, most plants will prefer a combination of dark and light cycles provided by nature. This allows them to go through their normal day/night cycle and absorb carbon dioxide during the night when there is little available light in the atmosphere for them to use for photosynthesis.
On top of this, having alternating periods of rest between exposure to different types of light also gives plants essential recovery time from any stress caused by too much sun or lack thereof. The result is healthier and more resilient vegetation overall.
As we can see then, there definitely appears to be an important role for darkness in helping ensure healthy plant growth. By providing ample opportunity for respiration alongside adequate amounts of light for photosynthetic activities, keeping up a regular schedule with different levels of illumination throughout day and night ensures maximum benefits for our flora friends!
No Plant Can Grow in Complete Darkness
You need to know that no plant can grow in complete darkness for a long time. Any plant will gradually die if not receive any light.
However, some plants can tolerate low light and managed to survive.
Here are some plants that need low light:
- Boston Fern (Nephrolepis exaltata)
- Pothos (Epipremnum aureum)
- Snake Plant (Sansevieria rifasciata)
- Ivy (Hedera helix)
- Cast Iron Plant (Aspidistra elatior)
- Chinese Evergreen (Aglaonema spp.)
- Weeping Fig (Ficus Benjamina)
- Lady Palm (Rhapis excelsa)
- Money Plant (Epipremnum aureum)
If you want your plants to grow healthily, you must understand the plant’s growth habits, as well as its sensitivity to the darkness. With this, you can provide more targeted light and dark treatments so that the plants can grow their buds as you wish. You should not blindly increase the duration of light and neglect the dark treatment, which may cause the plants not to bloom.
