How Many Hours Of Light Do Hydroponic Plants Need?

How many hours of light do hydroponic plants need each day? This article provides the required light for different types of plants.
How many hours of light do hydroponic plants need each day? This article provides the required light for different types of plants.

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Do you have an indoor garden of hydroponic plants? If yes, understanding how much artificial light is sufficient for the growth and development of your plants is a critical factor in their success. Without having the correct amount of quality light, many hydroponics plants can suffer from inadequate nutrition deficiencies or produce too little chlorophyll to support them properly.

To ensure that you can provide adequate lighting for your hydroponics, it’s important to understand how many hours of light are recommended for different varieties and how to adjust those numbers if needed. In this blog post, we’ll discuss what kind of artificial lighting should be used with hydroponics and provide guidelines on the number of hours plants need at optimal growing conditions.

How Many Hours Of Light Do Hydroponic Plants Need?


What Do You Need To Know About Hydroponic Lighting?

Hydroponic lighting is essential for those looking to use hydroponic systems to grow plants indoors. Keep in mind that different lighting types have unique requirements and can provide varying results, so it’s best to research before investing in hydroponic lighting. LED lighting fixtures are often great for hydroponics since they typically require less power and create significantly less heat than other bulbs.

While some LED lights focus on one type of light, such as blue or red, others feature color-mixing technology, allowing you to adjust the balance of light according to your plants’ needs. Additionally, check the light spectrum emitted by each fixture and the manufacturer’s recommended duration of blue and red light exposure for optimal plant growth. With many options available today, you can find the right hydroponic lighting system to meet your needs and budget.

How To Start?

Once you’ve chosen the right lighting system for your needs, it’s time to determine how many hours of light hydroponic plants should receive. When setting up a light schedule for your plants, a good rule of thumb is 18-24 hours per day in their early stages and 12-14 hours once they reach maturity. This will give them the amount of light necessary for photosynthesis and, in turn, optimal growth.

It’s important to note that this is only a general recommendation, and your plants may need different amounts of light depending on the species and their environment. In any case, it’s best to monitor your plants closely and adjust the light schedule accordingly if needed. For example, if your plants are not growing at their optimal rate, you may want to add additional hours of light or switch to an LED system with a higher color temperature.

Lastly, understanding how much artificial light hydroponic plants need is essential for achieving healthy growth. Once you have chosen the right LED light fixture for your hydroponic system, monitor the amount of light your plants receive and adjust the schedule accordingly. With the right hydroponics lighting setup, you can give your plants a healthy boost and ensure their success!

How Many Hours Of Light Do Hydroponic Plants Need?


Different Types Of Plants

Various plants can be grown in hydroponic gardens, and the amount of light they need to thrive can vary drastically between species. For example, some flower plants require multiple hours a day of bright direct sunlight for full maturity. In contrast, vegetables such as spinach may only require several hours of indirect light via a grow light from an indoor garden.

Other plants, like herbs, may do best with ten to sixteen hours of moderate-intensity light each day. Ultimately, deciding how much artificial lighting to give any hydroponic plant comes down to knowledge about the species in question and understanding its specific needs for optimal growth.

Plants Requiring More Sunlight

Plants that need a lot of light, such as spinach, wheat, lettuce,  potatoes, and turnips, typically require 16-20 hours of light to grow optimally. If the hydroponic plants don’t receive this amount of natural sunlight, they may require supplemental artificial lights to reach the necessary light requirement.

In addition, when using artificial light for hydroponic growth, you always want to ensure the correct spectrum of color temperature is used so that you don’t inhibit the plant’s overall growth. Still, it is important to note that excess lighting can increase temperature levels and reduce beneficial CO2 levels, so caution must be taken with your hydroponic setup if supplemental lighting is necessary.

Plants Requiring Less Sunlight

The amount of light needed depends on the particular species of plant; in general, hydroponic plants require approximately 12 hours of daylight each day to reach optimal growth and health. Some even thrive with as few as 6 hours.

Examples of plants requiring less sunlight are strawberries, poinsettias, cauliflower, and chrysanthemums. When caring for these smaller plants, it’s best to gradually increase the amount of artificial lighting or natural daylight when possible rather than subjecting them to too much sudden bright light. Keeping up with this balance helps your plants stay healthy and increase productivity.

Neutral day plants

Hydroponic plants of the neutral day type, including roses, rice, eggplants, and corn, require ample light for photosynthesis. The best option for providing such light is to aim for about 14 hours of daily light exposure.

As a result, the growing process is enhanced significantly as the plants receive all the necessary energy for their growth cycle. With this spare time allotted, all the plants in the hydroponic garden will have enough energy to grow and thrive properly.

Parts Of A Hydroponic Light System

When considering the light requirements for hydroponic plants. It is important to consider the components required for the lighting system. Generally, a hydroponic light system consists of a bulb, reflector, and timer.

The bulb should be selected carefully to ensure that it has the appropriate intensity level for the specific plant species.

A reflector will help maximize the coverage of the light emitted from the bulb and minimize dark spots or hotspots across your plants.

Additionally, by using a timer, you’ll have better control over when and how often your plants receive light and can ensure they get precisely as much as they need to thrive. All these factors must be considered to create an optimal growing environment for your hydroponic plants.

How Many Hours Of Light Do Hydroponic Plants Need?



Can Hydroponic Plants Get Too Much Light?

Yes, hydroponic plants can get too much light if your hydroponic plants are exposed to more than their desired light. It can cause them to become stressed and damaged. Too much light can also reduce beneficial CO2 levels in the air. So ensure you’re providing the right lighting for each type of plant in your hydroponic setup.

Can Artificial Light Be Used For Hydroponic Plants?

Yes, artificial light can be used for hydroponic plants as long as it provides the right spectrum and intensity of light for that particular species.
When using artificial light, always use a timer. So you have better control over the amount of light your plants receive. With the right balance, you’ll be able to ensure your hydroponic plants get all the energy they need for optimal growth and health.



The average hours of light plants need around 14 hours daily. If you are using an artificial light source, ensure it provides at least this much light daily. One way to ensure your plants get enough light is to use a light meter.

A light meter will help you measure the amount of PAR (photosynthetically active radiation) your lights provide. Keep in mind that the intensity of light decreases as it travels through water, so growing plants in deep water culture may need more intense lighting to reach the bottom of the roots.

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Mindy van Orden

I have grown hydroponic plants for decades, in different weathers. I'm a retired financial planner, born in Chicago, spent some time in Spain and Portugal. I currently live in South Carolina.

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