One common issue that most succulent plant enthusiasts face is the inability of these plants to withstand freezing temperatures. However, bringing these plants indoors, with the day hours shortened in winter and the limited natural light, will result in a leggy succulent stretch, succulent loss of colors, and other potential issues. 

Fortunately, numerous growth lights are popular and help many growers fix this condition. These growth lights simulate natural sunlight, allowing the succulent plants to thrive and maintain their colorful outlook, even when kept indoors. In this blog, you can find the answers to these questions:

1. Does the artificial grow light work on succulent growth?

2. Why and when to use grow lights?

3. What to look for in the grow light?

4. Types of grow lights for succulents.

5. How to use grow lights in the right way?

6. Common grow lights: Pros & Cons

7. Other useful tips

Do artificial lights exactly work on succulent growth?

The answer is yes. In general, succulents require at least 6-8 hours of high-intensity light per day. It is preferable to use a full spectrum or close to full spectrum light source. Full spectrum light consists of visible light, including red, blue, green, and other color wavelengths. Different wavelengths of light have varying effects on succulents. Red light (610-720nm) can promote plants flowering and fruiting. Blue light (400-520nm) can discourage leggy growth and increase leaf thickness. Green light (500-610nm) can enhance leaf pigment content and antioxidant capacity.

Different families and genera of succulent plants have varying light requirements. For the Echeveria genus, people expect compact yet vivid colors, so making a grow light that supports growth and coloration is a perfect choice. Sedum plants prefer a grow light with a larger red light wavelength and irradiation range, which is more appropriate for luxurious flowering. Harworthia can tolerate a short-term low-light environment. Put them near a sunny windowsill; their growth will not be greatly affected. 

However, sunlight as a natural thing is still the best option but we don’t do an extension here. Click here to learn more about sunlight care of succulents.

Why and when to use grow lights?

Using grow lights can help provide the necessary light for the growth of succulents. The lighting conditions are subject to various factors such as seasonal fluctuations, geographical location, and environmental conditions. Therefore, when considering what grow lights to choose, it is imperative to consider the specific needs of the succulent plants at hand, whether it is for succulents' optimal health, maintaining the shape and coloration, fixing low-light issues in winter or indoor growing needs, the implementation of grow lights is advisable. These artificial grow lights can simulate the natural spectrum and help you solve problems and achieve your needs.

What to look for in the grow light?

PAR

PAR, photosynthetically active radiation, is used by plant scientists and describes the portion of light that is useful for plant growth. PAR basically refers to the range of light from 400-700 nanometers (nm). PAR is not a unit of measurement as it only represents the light between 400-700nm required to support photosynthesis in plants.

PPFD

PPFD, Photosynthetic Photon Flux Density, is the amount of light that reaches the surface of your plants, measured in µmol/m2/s (micromoles per square meter per second). This is usually the number shown to you on a handheld PAR meter. PPFD is the most important parameter to growers because it shows the average light level on the growing space. The larger the number of micromoles, the higher the bulb intensity.

Full Spectrum

Full Spectrum refers to the spectrum curve that includes ultraviolet light, visible light, and infrared light. The spectrum of sunlight can be called the full spectrum, and the color rendering index is close to 100.

Full-spectrum grow light refers to lights that feature all the needed colors (for example, blue and red as mentioned before) that indoor plants need in their growing process.

Lumens

Lumens is a unit of measurement that determines the brightness of a light source. The range of light lumens that human eyes are sensitive to is 380-780nm. However, when selecting a grow light for plants or succulents, Lumens should not be the sole factor to consider.

Color Temperature

Color temperature represents the appearance of warm or cool colors of visible light and is measured in Kelvins. The color temperature of grow light is usually 2000-3500K, and the color temperature is generally 5000-7500K. Succulents are fairly forgiving on this metric, and lights from 3,000K to 6,000K can support healthy growth.

Image credit: eledlights.com

Wattage

Wattage is a measurement of power consumption. Wattage is primarily relevant in determining the cost of operating the light and the compatibility between the grow light and your power source. It is a valuable parameter when purchasing all electrical products.

Types of grow lights for succulents

When purchasing grow lights, the most valuable parameter is PPFD. Succulent grow lights can be divided into different types:

1. Grow lights that promote optimal growth: This type of grow light mainly emits blue light or has relatively high requirements on the blue light spectrum band. It can stimulate the chlorophyll synthesis of succulent plants, promote the growth of stems and leaves of succulent plants, and prevent the succulent plants from stretching out and growing leggy. A minimum PPFD selection of 75umol/m2/s is recommended, while 75-150umol/m2/s is suitable for seed propagation, young succulent babies, and other stages. These lights are ideal for succulents that need to grow lushly, such as Crassulaceae and Apricotaceae.

2. Grow lights can be helpful in promoting the coloring of succulent plants: These lights mainly emit red light or require a high amount of red light spectrum band. The red light can stimulate the production of carotenoids and other pigments in succulent plants, which can promote the discoloration of the leaves and enhance their ornamental effect. The minimum PPFD value recommended for such plants is 200 umol/m2/s. This value is suitable for succulent plants that require coloration, such as Cactaceae, Sedumaceae, Apricotaceae, and others.

 3. Full-spectrum grow light: This grow light can emit various visible lights such as blue light, green light, and red light. It can simulate the effect of natural light and provide comprehensive lighting conditions for succulents. Most full-spectrum LED grow lights, specifically for succulents on the market, have a PPFD between 100-200 umol/m2/s and meet various growth stage requirements. It's important to note that the higher the PPFD, the larger the distance between the succulent and the grow light should be.  For some large-scale professional plant grow lights, the PPFD value range is wider, between 400-1500 umol/m2/s.

How to use grow lights in the right way?

When using the grow light, it is important to keep in mind the following factors:

 1. The distance between the grow light and the succulents: The distance is a crucial factor that determines how evenly and brightly the plants are illuminated. In general, a shorter distance will result in higher illumination intensity but lower uniformity. Conversely, a larger distance will lead to lower irradiation intensity but higher uniformity. It is recommended to maintain a distance of approximately 12 inches between succulents and the grow light. This distance refers to the space between the top of succulents and the light. For succulents of varying heights, it is advisable to use the grow lights of different heights to prevent the burning of leaves in taller succulents.

2. When to turn on/off the light and how many hours of the light: Providing supplementary light according to the biological clock of succulents is recommended. In short, turn on the grow light in the morning and turn off it before night. 

If you have recently started using a grow light for your succulents, it is recommended to begin with 6 hours of light per day, from 10 a.m. to 4 p.m. Gradually increase the amount of time the plants are exposed to the light over the next few weeks. This will help live succulents adjust to the new environment more effectively. However, the maximum time per day is 16 hours and a reasonable time is 10-12 hours every day.

If the succulents are being grown indoors temporarily, they will be moved outside for planting in spring using the same gradual reduction principle. Otherwise, the biological clock of the succulents will be disrupted, which effects the growth and flowering of the succulents.

Common grow lights: Pros & Cons

1. Light-Emitting Diodes /LED light

Pros: Less heat, less power consumption, long life.

Cons: High price.

Niche groups: Advanced and professional succulent growers, those who expect more from succulent growing.

Recommendation: Full spectrum LED lights or professional LED lights with stronger red and blue light spectrums.

2. Fluorescent Grow Lights

Pros: Less power consumption, cheap price.

Cons: Incomplete spectrum, low light intensity, short life.

Niche groups: Those who are on a budget or new to succulents.

Recommendation: T5 lamp.

3. High-Intensity Discharge(HID) and Metal Halide(MD)

Pros: Cheap, strong luminosity.

Cons: High power consumption, low efficiency, high heat generation.

Niche groups: Professional planting farms.

In summary, for most succulent plants, full-spectrum LED lights or professional LED lights with stronger red and blue light spectrums are suitable. Although they may be expensive, it is still a good investment for long-term planting.

Other useful tips

1. Plant growth lights should be used as a supplement to natural sunlight, but they cannot replace it completely. Whenever possible, allow succulent plants to receive natural sunlight.

 2. Do not overuse plant growth lights; otherwise, they will cause light damage to succulent plants, such as the leaves getting white, thin, soft, black, etc. According to different varieties of succulents, choose the appropriate switching time and duration of plant growth lights. Typically, 10-12 hours a day is recommended.

3. When using the grow lights, you'll also need to adjust other maintenance tasks to ensure that your plants continue to grow healthy and strong. This includes paying attention to their watering needs, providing the right fertilizers, repotting as necessary, and carefully pruning any excess growth. 

4. Plant growth lights can be positioned at different angles and locations to create various effects depending on the scene and purpose. Succulents can benefit from top/front illumination and side illumination to enhance their shape and colors. On the other hand, illuminating them from the back can add a touch of mystery and artistry that some growers find enjoyable to observe.

5. For different locations, such as balconies, windowsills, greenhouses, or plant stands, you should choose the grow light equipment suitable for different spaces and layouts. Some grow lights have the function of flexibly adjusting height and angle to meet the needs of light range and intensity in different scenes.

As the demand for green plants continues to grow, people are paying more attention to the combination of nature and home life. Plant growth lights have become an indispensable tool for indoor planting, bringing joy and happiness to gardening enthusiasts. With the help of plant growth lights, the constraints of season, climate, and space are no longer an issue, allowing you to observe and understand the growth and changes of succulents more easily. This can increase your knowledge and interest in succulents and make it easier to connect with others who share your passion. By sharing your thoughts and experiences on succulents, you can make new friends and create a more social and warm atmosphere for your succulent planting.