It is a known truth that plants need light to stay healthy, however, this becomes a problem when they are kept in an indoor environment. In addition to sunlight, photosynthesis has some surprising components that go well beyond it; even plants that are housed indoors and do not receive any sunlight are able to convert light into energy. Indoor plants, however, lack natural light, so how do they photosynthesize?
All light sources available to indoor plants are converted into chemical energy during photosynthetic activity. Plants do not need sunlight to photosynthesize, and any light source is enough because it triggers chemical reactions.
In this article, we will discuss how indoor plants are able to photosynthesize with minimal sunlight or no sunlight at all, since many biological steps of photosynthesis are the same for indoor and outdoor plants.
You can expect some nerdy material below. Continue reading after you have adjusted your pocket protector.
Photosynthesis 101: An Overview
Photosynthesis is taught as part of elementary school science curriculum, although it is always a good idea to revisit the process so that indoor plants can produce energy without complete sunlight.
This is the first misconception about photosynthesis: plants do not need direct sunlight to photosynthesize. In fact, they do not even require sunlight to convert light into energy.
Because photosynthesis is triggered by any light source, whether it be sunlight or a simple lamp near an indoor plant, any light source plays a role. Since we were always told to grow plants in sunshine as children, it can be difficult to reconcile this fact.
As light is just one of four components of photosynthesis, we should examine each part individually to better understand how the process takes place.
Light and soil, along with water, are three factors essential to the growth of plants. It is impossible to grow plants without light, which is absorbed by plants during photosynthesis. Light is absorbed by chlorophyll in the leaves and stem of a plant and attaches to the chlorophylls that are attached to the protein membranes.
Using the captured light, electrons in water are removed, which allows the energy to be transferred.
The Transfer of Electrons
When new electrons are introduced into a cell, they are transported throughout the nucleus until they encounter a new electron acceptor, where the movement of electrons is coupled to the movement of protons across the thylakoid membrane, forming a pH gradient.
A force of sorts is created between the newly converted electrons and the newly converted energy provided by them.
The electrons have been converted to energy, so amino acids containing energy are produced. ATP (adenosine triphosphate) then carries this energy throughout the plant, which powers every function it needs to function properly. The proper chemical reactions in living things are caused by ATP compounds, which are derived from a nutrient source, which in the case of plants is light.
Although the first three stages of photosynthesis occur during the absorption of light, the final phase can occur with or without light, which is one of the main stages of photosynthesis exhibited by indoor plants: carbon conversion. It involves all of the electrons and molecules generated in the first three phases resulting in the transfer of nutrients to every part of the plant.
Light is one of the primary factors in photosynthesis, but the easiest way to think of it is that it is like food for plants. It is just as essential to plant growth as water to provide the processes that create nutrients.
Let’s learn how photosynthesis can occur indoors for plants receiving little or no sunlight now that you have a better understanding of the process as a whole.
How Much Light Do Indoor Plants Need to Photosynthesize?
The same is true for indoor plants, as they will die in the absence of light. In the absence of light, chlorophyll cannot be produced, so the plant will essentially turn white or yellow before dying. In addition, plants without light will grow a long stem through the process of trying to reach a light source.
As a result, it may sound surprising to discover that short exposure to light is sufficient to initiate photosynthesis within a plant. Besides light, plants also require carbon dioxide and water to carry out photosynthesis. Light is the primary component, but those two factors are also necessary.
Plants can differ in how much light they need to photosynthesize according to their species. In the case of indoor plants, they can fall into that group of plants that require shade, so while they may take 2-4 hours to photosynthesis each day, they will continue to thrive.
You should not put an indoor plant directly under the light, but you should leave it near a lighting source to be on the safe side. In a light-filled environment, the sun’s rays will be able to reach the exterior of the plant to kick-start photosynthesis.
How Do Indoor Plants Photosynthesize Without Sunlight?
Plants require sunlight as their primary source of light. Sunlight contains all six visible light spectrums—yellow, red, blue, indigo, violet, orange, and green. So, no plant will be deprived of any of the necessary spectrum to grow properly.
In light of this, plants require only two light spectrums for growth: red, which promotes buds, and blue, which promotes growth. In addition to light intensity and duration, depending on the plant type, photosynthesis can also be affected by absorption.
Plants that are common indoors do not need high intensity or prolonged exposure to light as these types of plants have evolved to find unique ways to photosynthesize when there is limited light available.
Let’s look at each variable in more detail to understand how plants survive without sunlight.
Types of Indoor Plants
It may shock you to learn that even small amounts of sunlight can stimulate photosynthesis in indoor plants. Before we explore the ways you can supply supplemental forms of artificial lighting to your plants, let’s talk a bit about how sunlight triggers photosynthesis. The fact that plants cannot survive in direct sunlight is obvious because many of them would die during the evening if that were the case.
The majority of plants require only 4-6 hours of direct sunlight per day, while other plants can thrive partially in the shade and can photosynthesize with just brief reflections of the sun once the shade is lifted. As a result, indoor plants are capable of photosynthesizing because they require a very low level of sunlight, which is why they can grow indoors.
We must keep in mind that some plants require some sunlight to thrive. However, most indoor plants can survive without it, so let’s see what supplemental lighting sources can do to trigger photosynthesis.
Are you aware that plants can grow even without sunlight if they are only given artificial lighting? The conventional light bulb is definitely good for plants, but there are other types of light sources that are better. I’ll share some with you.
In terms of artificial light for indoor plants, LEDs (light-emitting diodes) are the most popular. The heat generated by LED lights is lower than that of other artificial light sources, such as regular light bulbs.
In addition to its brightness, LED lights are also very efficient. Additionally, LED lights are available as screw-in replacements for lamps or targeted, high-intensity greenhouse models that can be suspended directly from above indoor plants.
It is the ability of LED lights to deliver a full spectrum of light that makes them a great alternative for indoor plants. Some LED light products can also be tailored to only provide specific spectrums based upon the plant’s lighting requirements because most plants don’t require all of the spectrums found in sunlight.
Furthermore, most LED lights have the capability of dimming or brightening in intensity if the plants are light sensitive.
Despite the fact that incandescent lights provide good supplemental lighting, they are usually targeted towards only a few different types of indoor plants such as those that are tolerant of high temperatures. When it comes to light intensity, incandescent lights are generally low, so the main focus will be on heat rather than light when it comes to plants.
For plants that require a lot of light, incandescent lighting is not recommended. If you have ferns or vines you can use this type of light.
For indoor plants, fluorescent lights are ideal since their intensity is usually at a medium level between that which most plants require and that which would be considered too intense. As a result of this type of light, you can provide a precise beam of light without having to fill large areas.
In addition to full spectrum lighting, fluorescent lights also produce warm and cool tones that differ from the harsh glare of incandescent lights.
Fluorescent lighting is very popular in greenhouse settings because it is strongly focused on the exterior of the plants while not being too bright or overly warm; it is the perfect balance.
The advantage of fluorescent lighting is the way it provides a perfect balance of kelvins (K), which is a measure of how much light is being produced. A Kelvin is used to measure absolute temperature in a wide range of objects, including light.
Kelvins measure the visual warmth of a stream of artificial light, so that white light has a ‘cool’ glow, whereas kelvins measuring a red or warm temperature means the light is warmer than it is cooler, which is commonly found in incandescent lighting.
Fluorescent lights have a high kelvin value, usually in the range of 6500 watts. In other words, the light is intense, but not overly warm. During the winter season, warm temperatures are sometimes important, but most indoor plants do not necessarily require excessive light in conjunction with warm temperatures.
It is okay if you choose to provide your plants with minimal sunlight during the day so you do not need artificial lighting. Photosynthesis can be triggered by placing the plants near a window where they will receive a few hours of sunlight every day. When it comes to indoor plants, another question to consider is the amount of light that is too much for them.
Light Requirements for Indoor Plant Photosynthesis
Because light requirements are directly correlated to plant type, the amount of light available is only suitable for plant types that need sunlight to survive, which includes a variety of outdoor plants you may want to grow indoors.
If this is the case, you should try to choose rooms that have bright lighting and large windows since apartment dwellings do not usually have yards.
When this occurs and you want to raise a plant that needs sunlight, be sure to place the plant directly in front of the light with no shade or objects blocking the rays. It is important to remember that, if your apartment has multiple rooms, the brightest light will come in through the south-facing window. Place your plant in this window if possible.
Sunlight must shine directly on leaves and stems of plants that need it.
If your indoor plants are of any other kind, you can use artificial light sources to activate photosynthesis. In order to photosynthesize indoors, plants require an intensity and spectrum of light depending on the type of chlorophyll they contain. Chrorophyll a, which absorbs red and violet light, as well as chlorophyll b, which absorbs blue and red light, are both found in plants.
Because of this, artificial lighting tends to have a wide range of shortcomings. As plants are able to photosynthesise, they require an intensity of light that they call the light compensation point. It is a process in which the amount of carbon dioxide absorbed is compensated by the amount of carbon dioxide released.
As a result of the light source’s intensity, the oxygen of the plant is compensated.
The intensity of the light source affects the amount of photosynthesis that can take place. Since LEDs and fluorescent lights are highly concentrated energy sources, which is in contrast to incandescent light, which mostly depends on the heat of the red and warm light to emit, LEDs and fluorescent lights are best.
When it comes to indoor plants, getting the full spectrum of light from the sun isn’t always an option, so you will need to make sure that blue and red light are provided at the very least. In relation to photosynthesis, let’s examine each color.
When it comes down to its most basic components, light is primarily composed of red, blue, and green. Due to chloroplasts within the plant, green is not effective for plants and bounces off of the leaves, turning the leaves blue and red. As blue light stimulates chlorophyll production, it is by far the most important light color for plants.
Plants and blue light both need certain nutrients for good health, just as the human body needs certain nutrients for good health.
Chlorophyll can take advantage of the blue spectrum of light more effectively than it can the red and far-red spectrums. A greater proportion of the blue end causes the cells to elongate, leading to a more compact growth pattern with closer nodes. In this way, each leaf is provided with the maximum amount of light and space.
Blue light is essential for plant growth and the proper functioning of plant processes.
In the same sense that blue light increases the size of plant parts, red light increases the development of plants such as seed germination, the growth of roots, and the blooming of flowers. A plant’s overall appearance is determined by the red light it receives. Since plants are visually appealing, red light plays a major role in the appeal they have to people.
Blue light can make a plant grow well and stay healthy, but red light is essential for keeping it looking attractive.
Since LED or fluorescent lights are primarily composed of red and blue light, they provide plants with the maximum amount of blue and red light needed for proper photosynthesis.
Due to the fact that the sun always shines at an angle where plants can absorb its rays, indoor plants require different directions in order to maintain the optimum light intensity needed for growth and development.
The plant should be monitored to make sure that it doesn’t wilt or change coloring, or to make sure it doesn’t thin out; if any of these occur, the plant is likely receiving too little light or too much light, respectively.
Indoor plants with low or medium light needs benefit from one or two fluorescent lights placed near the plants but not directly on them. The light will be able to reach the plant and not cause it to dry or burn, since photosynthesis can occur from any part of the plant (laves are best).
The best way to determine if your indoor plant is getting too much light or too little is to watch how it appears over a few days. In the event the leaves look withered or the stem looks thin and reaching towards the light, direct sunlight should be applied.
If your plants appear bleached or scorched, you should keep them at a distance.
How Do Indoor Plants Photosynthesize With Little or No Light?
It is impossible for plants to photosynthesize in perpetual darkness. Although it may seem impossible, indoor plants can fully thrive without visible light. Despite the fact that blue light is more beneficial to plant growth, plants actively seek out both red and far-red light.
Similar to this can be seen in how people crave sugary foods despite the fact that lean meat and vegetables are the healthiest foods.
In addition to blue light, far-red light can enhance plant growth by an impressive margin; therefore, plants that may be lacking light will seek out red light sources and reflect more far-red light, which will be made even more competitive if there are other plants nearby. The phenomenon of photoreceptors mimicking this behavior isn’t as weird as it may sound-if there is a lack of light available in an area, plants mimic this behavior.
If a plant is deficient in blue light and is exposed to more red and far-red light, it will experience nutritional imbalances, and abnormal growth and development will occur, potentially leading to death.
While this is the normal pattern for plants with adequate light needs, indoor plants that need minimal amounts of blue and red light may be able to achieve adequate photosynthetic activity with only minimal amounts of both light.
Light and Dark Phase
Due to the fact that photosynthesis has both a dark and a light phase, a small amount of light is sufficient to activate photosynthesis, and in the case of indoor plants that require very little light, this will suffice. At this stage in the process, the chemical reactions taking place take center stage.
As a result, a plant which receives only a small amount of light will cycle through, therefore receiving some nutrition, but not enough.
An Indirect Approach
Additionally, there is a process whereby the available light can be used indirectly to facilitate photosynthesis. When you place your indoor plants away from a light source, such as an open window or an artificial light, the light can be reflected from a variety of different objects within the room. As a result, the plant does not receive far too much direct light, which is actually optimal.
To ensure that your plant is in good health, check the plant’s guidelines to find out whether it needs low, medium, or direct light. As long as the light is close by and is sustained for at least 4-6 hours, your indoor plants will be able to photosynthesise.
Photosynthesis may seem like an easy process, but depending on the type of light and the needs of a particular plant the process can become complicated. As with outdoor plants, indoor plants photosynthesize as well. Therefore, artificial light sources can be utilized to achieve photosynthesis as long as they provide plants with red and blue light.
Despite the fact that indoor plants do not usually require much light, you should check the light intensity from time to time to make sure it is appropriate for your plants.