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How many hours of daylight do plants need?

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The sun is the main energy source for almost every living thing. Sunlight especially is essential for plants since it’s only plants that use sunlight to produce oxygen which is the air that humans and most animals breathe.

A plant may need at least six hours of direct sunshine, whereas most survive with roughly three to six hours daily. At the same time, the plants need protection from the intense sun, so don’t leave them directly in the sun for too long.

It also helps to search for your specific plant’s sunlight needs because they differ from plant to plant.

How does a plant use daylight?

Plants depend entirely on the energy from the sun to reproduce. Key processes like photosynthesis take place in plants when they get direct sunshine.

Photosynthesis is the process whereby green plants transform light energy into chemical energy.

In this photosynthesis process, the plants’ energy produces by-products such as oxygen and sugars in plants. According to research, the carbon dioxide in the air combines with the plants’ water to produce sugars and oxygen in a series of reactions.

Plants need a specified amount of sunlight, so sometimes, when the plants absorb a lot of sunlight than needed, the excess energy may cause critical damage to the plant’s proteins.

What do plants do with the excess daylight that they receive?

To protect themselves from the excess energy, the plants convert it to heat and send it back to the environment. Depending on the amount of energy absorbed, the plants can reject 70 percent of the sunlight’s energy.

In cases of sunlight deficiency, the plants store energy in starch. They are complex carbohydrates that can be broken down to glucose for plants to use for energy.

Why do plants need daylight?

All living things need the energy to grow. We get energy from the food that we consume. Plants get their energy from light through photosynthesis without light; the plants will be unable to produce the energy they need to grow.

This process will be further explained in the next part and its stages.

Process of photosynthesis

Photosynthesis is a complex process with two main stages.

The first is the light-independent stage, where the sunray hits the leaf’s surface. Then the light-absorbing pigment chlorophyll divides water into oxygen and hydrogen ions.

The second stage is the light-independent reaction. The plants use the energy from the light reaction to convert carbon dioxide into glucose through chemical reactions. Plants use glucose in many ways; it converts into chemicals needed for the plant’s growth and can also break down during respiration to release the stored glucose molecules.

Do indoor plants need daylight?

Indoor plants also require daylight. As mentioned earlier, we’ve seen that all plants require light to produce energy used to stimulate growth, strive, and even then, the plant stays alive.

When it comes to indoor plants, they need daylight and enough lighting. There are three lighting factors to consider that highly affect the growth of an indoor plant:

  • The amount of light disposable for the indoor plant. This is the number of hours of daylight exposure on your plant.
  • The spectrum. This is the warmth of light or the color of the light (from dimming to bright colors).

If a plant doesn’t get enough light from the sun, it slows down the photosynthetic process, thus slowing down the plant’s growth rate.

Signs that your plant is not getting enough daylight

Below are the symptoms in specific parts of plants that show the lack of sunlight intake for plants:

Effect of lack of sunlight intake on growth Effect of lack of sunlight intake in specific plant parts
Your plant will have stunted or no growth.For flowering plants, they fail to bloom
New shoots grow (reach out) towards the light.The new leaves of the plants become smaller than the pre-existing ones.
Growing with long spaces in between the leaves.

Suppose an indoor plant cannot access natural daylight, maybe during winter. The days are shorter than the night, and the light intensity might be lower.

You can use artificial lighting to provide the sun’s spectrum of wavelengths. Fluorescent lights are the most effective because they provide the type of light that plants need for photosynthesis.

Do specific categories of plants need direct sunlight?

As mentioned previously, different plants have different needs, which will be the same for different plants.

The cactus thrives in the desert while the fern thrives in the wetland.

The fool will try to plant them in the same flowerbox.

The florist will sigh and add a wall divider and proper soil to both sides.

The grandparent will move the flowerbox halfway out of the sun.

The child will turn it around properly so that the fern is in the shade, and not the cactus.

The moral of the story?

Kids are smart.

Vera Nazarian, The Perpetual Calendar of Inspiration

Flowering plants and their needed sunlight

Most flowering plants require full sun provided their required moisture is maintained. Most days, they should receive six to eight hours of direct sunlight to ensure they grow properly.

An example of a flowering plant that loves the sunlight would be roses, wherein this plant species require at least half of the daily sun time.

Needed amount of sunlight for Vegetable plants

Vegetable gardens do well when positioned in the sunniest location. Although some vegetables and herbs (mostly leafy) don’t do well in direct sunshine, others might require shade.

Most plants that require full sun while flowering are the biggest group of plants you will come across.

Providing the moisture requirements are met once they become established, set up a two-to-three-inch layer of mulch that will help preserve soil moisture and keep the roots cool.

You should also know that most sensitive plants cannot flower under direct sun. The best way to handle them is to ensure the plants get most of their sunlight in the morning or very late in the afternoon when the temperatures are slightly cooler to flower properly and grow well.

Herb plants and their daily sunlight needs

Herb plants, like flowering plants, usually require at least half a daylight amount of sunlight (6 hours). Leaving them lacking sunlight may bring about spindly or leggy legs in their stems and leaves, as further explained in this article about herbs and their need for sunlight. You can check them out here.

But again, like other things, this does not cover the needs of every herb out there! Some also prefer dappled light and such, so it is important to research to see what makes your herbs thrive.

Things to do for plants for them to achieve their daily sunlight intake

Before getting a specific plant, it is always advisable to research its needs, common habitats, and what it takes to make them flourish.

There will be many books, resources, and even tutorials out there for your chosen plant, so take advantage of all of that information and learn about their specific sunlight intake hours, the advisable placements of the plants (may it be an indoor or outdoor plant) if they need to be filtered light or will be well with direct sunlight and so so and so forth.

While most plants do prefer direct sunlight, select plants prefer filtered sun. An example would be orchids, which are best kept as indoor plants with controlled humidity and sunlight around them to make them bloom.

But there are also plants, even indoor ones, that thrive and love direct sunlight, and the aloe vera plant would be one of them.

As seen here, both orchids and aloe vera are famous indoor plants, but they have different sunlight needs, which further reminds us that what works for one plant might not work for the other.

Usage of different types of lighting

Outside of just plain old sunlight, there may be other types of lighting needs that your plants have. Some can use artificial or supplemental light.

Supplemental lighting can be used in cases lacking natural sunlight, and many artificial lights can best fit your needs. These may come from the needs of some plants that are extremely sensitive to heat; hence come with requirements to stay under a shelter in hot climates.

But either way, understand that plants can’t do without some form of lighting. Whether natural or artificial, light plays an important element in the life growth of a plant. If possible, however, you should always choose natural lighting over artificial lighting.

Conclusion on how many hours of daylight do plants need?

Sunlight is the food for plants, and the exposure to it will vary in different plants; that is why comprehensive research on the species is critical to know if there might be any limitations.

Initially, we admit all the searching may be a hassle, but your little research can pay off and make your plant thrive. All this will make the blooming and growing process much more fulfilling and happy, knowing that you did your best for your plants.

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