Growing cannabis indoors has become an increasingly popular practice, and the use of LED lamps has revolutionized the way many growers carry out their projects. However, if you are thinking about an early retirement for your HPS equipment and take the leap to this type of lighting, or have already done so, it is important that you know the most common mistakes that can affect the performance of your crop.
There are a number of factors that you should take into account when using this type of grow lamps, small details that may not seem important to you but that will make the difference between a successful harvest and a disappointing one. Today we invite you to discover them and get the most out of your brand new LED panel. Let’s go!
Growing cannabis with LEDs, a growing trend
LED lighting systems have gained much popularity in the cannabis growing world, and it’s no coincidence. Compared to traditional HPS or CMH equipment, LEDs consume less energy, generate less heat, and can offer specific light spectra for each phase of growth, which is why, on many occasions, they have ended up displacing traditional discharge equipment. In addition, thanks to their technological evolution, more and more growers prefer them for their efficiency and durability…the results are getting better with each passing year!
However, despite its many advantages, switching to LED isn’t just about plugging in your new equipment and expecting magical results. Adapting your growing method to this technology is key to making the most of the potential it offers you. It’s essential to understand how LED panels work, what light spectrums they use, and how to adjust their parameters for each phase of cannabis development. Only then will you be able to get the most out of this technology.
Main features of LED grow panels
LED panels for cannabis cultivation have some fundamental differences compared to other light sources such as classic HPS or CMH equipment. Some of their main features are:
- Energy efficiency: They consume less electricity compared to HPS lamps and generate less heat, reducing the cost of the electric bill.
- Custom light spectra: Many models allow you to adjust the light spectrum according to the development phase of the plants (vegetative or flowering), improving their response to artificial lighting.
- Long lifespan: A good LED panel can last between 50,000 and 100,000 hours of use, making them a long-term investment.
- Less heat emission: This reduces the risk of heat stress in plants and makes it easier to control the climate in the crop, allowing for a more stable environment. In many places, they represent the only way to be able to grow indoors during the hottest months of the year.
- Better light penetration: Some high-quality models allow for a more even distribution of light, ensuring that all parts of the plant – and all areas of the growing area – receive adequate lighting.
Now that you know the main benefits of this type of lighting system, let’s look at the most common mistakes you should avoid when using it.
Main mistakes when growing with LEDs
While LED panels offer many advantages for growing cannabis, they also present specific challenges that can affect the health and development of your plants. Many growers make mistakes due to lack of knowledge or by not adapting their technique to this type of lighting. No, as we have told you before, it is not as easy as unplugging your old HPS and connecting your new LED. Below, we present the most common failures that can compromise the performance of your crop and how to avoid them to get the most out of your LED lighting equipment:
Incorrect location and distance of LEDs
One of the most common mistakes is placing the lights too close or too far from the plants. If the LEDs are too close, they can cause light stress, causing leaves to curl or burn. If they are too far away, the plants can stretch excessively in search of light, weakening their stems. The ideal distance varies depending on the wattage of the panel, but generally ranges between 30 and 60 cm. It is always advisable to follow the manufacturer’s instructions and adjust the height based on the response of the plants. As you will see later, using a PAR meter will allow you to know exactly how much light your plants are receiving, allowing you to adjust the height of the lamp to the correct distance.
Lack of adjustment in the light spectrum
Not all phases of cannabis development require the same light. Many novice growers forget to adjust the light spectrum on models that allow it. For the vegetative phase, a blue spectrum (400-500 nm) is recommended, as it promotes strong and compact growth. In flowering, red light (600-700 nm) should be prioritized, which stimulates the production of buds and resin. Always keep this in mind and don’t forget to change it when modifying the photoperiod of your plants.
Do not supplement with other environmental factors
A common mistake is to think that LED lighting alone is enough to obtain large yields. Temperature, humidity and ventilation are equally crucial. Since LEDs generate less heat, you may need to adjust the ambient temperature to optimize growth, for example by adding a heat source during the colder months of the year. It is advisable to maintain a temperature between 22-26°C in the vegetative phase and 20-24°C in flowering, although as you can see in the following link the ideal temperature will also depend on humidity. In addition, proper air circulation prevents the appearance of fungi and pests.
Vapour pressure deficit (VPD) in cannabis cultivation
Temperature and relative humidity play an important role in indoor marijuana cultivation since much of the plant’s activity depends on these factors. Incorrect values of these two parameters will result in an invalid VPD (vapour pressure deficit), which will in turn result in poor plant development. In this article we explain how to properly adjust these values so our plants can enjoy a good climate for an amazing development.
Using an inappropriate LED panel
Not all LEDs are suitable for every type of crop. Often, growers choose panels with low quality or insufficient power for the surface they want to illuminate. It is important to do research and choose an appropriate model based on the size of the crop and the needs of the plants. As we have already mentioned, it is also advisable to use a PAR (Photosynthetically Active Radiation) meter to know the exact amount of useful light that the plants receive and thus optimize the distance and power of the lamps.
Excess or deficit of irrigation
Switching to LED also affects watering. Because LED panels generate less heat, water evaporation or transpiration is lower, meaning plants may need less watering than with other light sources. Failing to adjust this variable can lead to overwatering and, consequently, to problems such as root rot. It is advisable to use well-aerated substrates and always check the humidity of the growing medium before watering.
Calcium and magnesium deficiencies
Cannabis plants grown under LEDs can develop calcium and magnesium deficiencies more easily, as LED light influences the absorption of these nutrients. To avoid this, the use of specific calcium and magnesium (Ca/Mg) supplements in irrigation is recommended, especially if grown in inert substrates such as coco fibre or hydroponics. If you decide to start your crop without this extra supply, keep a close eye on your plants to detect any nutritional imbalance as soon as possible.
Not keeping track of plant development
Every crop is unique, and while LEDs are a great tool, you should monitor your plants’ response on a daily basis, especially during the first few grows you do with your new lighting. Adjusting the height of the lights, the intensity or the exposure time can make all the difference in the harvest. Keeping track of your plants’ development and detecting potential problems early will help you maximize results and become an expert in record time.
LED lights have revolutionized cannabis cultivation, offering efficiency and excellent results, but as you can see, their use requires certain adjustments and knowledge. Avoiding mistakes such as poor distance from the lights, inadequate watering or choosing the wrong panel will allow you to maximize the quality and quantity of your harvest.
Additionally, paying attention to proper calcium and magnesium supplementation, as well as using tools such as a PAR meter, can make all the difference in the success of your grow. If you pay attention to these details and keep a constant track, you will be on your way to becoming an expert LED grower. Of course, you can leave us your questions or comments in the corresponding section, we will be happy to answer you.
Happy harvest!
