How many watts do I need for a 4×4 grow tent?

Wondering what size led grow light do you need?

Here How to Calculate how many watts per square foot for led grow lights your plants actually require to provide excellent growth.

Setting up your own grow space?


A great growing system is composed of the appropriate room size, soil, plant density, relative humidity, the right temperature, proper air circulation, and the perfect LED light.

But this where things can get tricky. You might have heard that wattage will dictate the light’s power.

While this is partly true, wattages do not exactly equate to power output. Although, wattage is one way to establish the light output needed for your plants.

What matters is the amount of usable light reaching per square foot of your growing area.

Generally, your goal with LED panels should be 32 watts per square foot of a grow space to get the best results. However, this would still depend on your growing conditions.

You have to determine the size of your grow room, consider PAR and PPFD levels, and identify plant density to secure the correct led wattage for your grow space.

Sounds like full of numbers and acronyms?

Don’t fret, we have simplified calculations in this post so you can easily convert the light intensity you need in watts per plants.

We’ve also included tables so you can see how many watts per square foot for led grow lights you actually need, actual grow space size, and different growth stages.

Determine The Size Of Your Grow Space In Square Meters

Your actual grow room space is a critical aspect in determining the wattage needed per square foot.

First, you have to take the width of the area in meters and multiply it by the depth in meters.

Then, simply follow this formula: multiply the width by the depth in meters.

For instance:

  • 4 foot x 4 foot x 1.2m x 1.2m =44 square meters

Normally, 1 square foot of a marijuana grow room needs about 32 watts of actual wattage.

Here’s a table showing the usual wattage for different sizes of a grow space.

Understanding PAR Output

You’ve probably heard about PAR. In simple terms, It’s the part of the light spectrum that your plants use for photosynthesis. So It’s a pretty big deal. The higher the PAR output of your light, the more edible light your plants receive. Take a look at the table below for the optimal ranges of PAR for each stage of your plans life:

Best LED Setup For 4 x 4 Grow Tent.


ECO Farm grow tent has all stable construction, 600D oxford cloth outside and 96% highly reflective waterproof diamond Mylar inside, with exterior zippers design ensure safety use and easy to set up. And it also has multiple vents to accommodate fans and filter. Great for you to grow exotic fruits, herbs, vegetables or seasonal fruits out of season. We promise to provide you with the highest-quality hydroponics equipment and services at our factory-direct prices.


Improper use of UV IR may have a negative effect on your plant.

Proper use of UV IR containing luminaires to ensure your plants grow better and get more trichome density and THC content.

The role of UV: Increasing the THC content of plants ,only be used in the last two weeks of flowering stage, and if be used at other times in the plants,may have a negative effect on plants.

The role of IR: Increasing the number of flowers , only be used in the early flowering period and stopped once buds begin to appear. This requires the IR and UV must be individually controlled.

Show More

Related Articles

Back to top button

buy windows 11 pro test ediyorum