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It finally happened: you decided that it makes more sense to have your own grow room than keep spending money on buying the product. But among other questions (assuming you have the room itself already), there are those of equipment. Light is as important a condition as, say, soil or humidity. So it requires a lot of attention.

Should you buy a premade LED grow light 4×4, or does it make more sense to master HID lighting? How many watts are required for plants to grow as they should? And what else should you consider? Let’s break it down.

LED, HID, or…?

There are many lighting technologies that are used to provide light to growing cannabis plants. Let’s list the most popular of them.

• HID (High-Pressure Sodium, Metal Halide). These two types are often viewed as one type because they are similar in construction and because you’ll need them both. MH bulbs are the best for the vegetative phase, while HPS lamps are better for flowering.
• CMH (Ceramic Metal Halide). These are a step up from the traditional MH as they provide more light and last longer. Yet they share some drawbacks like excessive heat.
• Fluorescent tubes. These are more expensive but allow for a fine light setup. They are fragile, though. Some old models make a buzzing sound and may flicker when turned on. But new models seem to exclude those problems.
• LED. The ubiquitous technology may be more expensive than HID, but it allows for creating all-in-one solutions that contain all the diodes necessary for different phases, emulating the sunlight better. In addition, these are eco-friendlier and require less power.

So, LED solutions are the way to go for a beginner or an eco-concerned person.

How Many Watts per Plant?

To answer this question, we need to choose the lighting type first. It’s the simplest to choose LED lights, so all the calculations below will apply to them. LED are also the easiest to install.

The general rule says that you need 32 W per square foot if you grow one plant on each square foot. A 4×4 grow room we review would require 512 W in general. This rough calculation, though, doesn’t consider inevitable energy losses, so, in reality, the power should be a bit above this value.

This level of precision from the previous paragraph is unreachable in real life. So, you can take the range 500-650 W per 16 sq. ft. and use it regardless of the number of plants. You won’t be mistaken if you choose a light device that lies within this range.

If you still decide to use HID (at least as a backup option), you need to keep in mind that they are not as energy-effective, spending about 38-40% of the energy on simply heating the air around. So you need to make adjustments in your calculations and take measures to protect your plants from that excessive heat by using coolers and moving the lamps higher away from the tops.

What to Search in Lighting Devices?

When you know what area to cover and thus how powerful the light source should be, it’s time to mind the extras. Here is a list of what else to search in lighting for grow rooms.

• Different types of light. In the perfect world, you should be able to switch between white, blue, pink, and red LEDs. In reality, blue ones are not that necessary, but it’s better to have all the others and the ability to switch between them.
• A built-in dimmer. At different phases of their lifespan, plants need various level of light, from 20% to 100% of their power. A dimmer or at least a switch will be perfect to adjust it according to the phase.
• Built-in fans. Even eco-friendly LED lights generate some heat, so fans must recompense it.
• Protection. The lights will operate under problematic conditions that include, among all, high humidity. So, moisture protection is necessary.
• Compatibility with smart home systems. If you have to leave your grow room even for one day when it needs your intervention, you better program it, so light modes change automatically. It’s especially important in the flowering phase when the plants should not get more than 12 hours of lighting a day.
• The price. Hardly will you want to overpay for overkill. It does make sense to buy a cheaper and less powerful LED panel meant for other plants, but it may not help growing flowering ones. Choose it due to the plant type.

Drop the Crop!

After all, you may conclude that an optimized LED panel for the size of your grow tent is the best solution. In many cases, though, with experience, you’ll understand where it goes wrong and how to optimize it. But as the option for beginners, we’d recommend sticking to LED. We hope we have helped you make your choice, and later you’ll get even higher.