How Many Lumens for Seedlings Needed for Marijuana Grown Indoors

If you are growing your marijuana indoors, you exactly know how challenging and complicated things are because you need to mimic the effects that are coming from our Mother Nature most especially on how many lumens for seedlings are needed for plant growth. In short, if you are growing indoors you have to spend big amounts of money and extra effort to be able to give your cannabis plants a comfortable and healthy lifestyle.

You have to give your plants, air, water, perfect grow room temperature, nutrients, and sunlight by means of grow lights to promote the growth of your cannabis plants. But the question now is, how much intensity of light you need to provide in your cannabis plants if you are growing indoors? And how many lumens are needed for marijuana grown indoors?

How Many Lumens for Seedlings Are Needed For Beginners to Know

This may sound too confusing most especially for beginners. But since we do care for you and we want you to harvest good crops of cannabis, we will give you a brief and simple explanation about the ideal lumens, watts, and whatsoever that is related to grow lights to avoid confusions and get the direct answer to your question.

What is the meaning of “Lumens”?

To put it simple terms, lumens are equivalent to brightness. If you are looking for a grow light with higher or lower brightness, you need to use the term lumens to be able to find out what type of bulb or LED light bulb to use for your cannabis plants.

So the next time that you will encounter the word lumens, you already knew that it is totally different from watts since watts are referring to the use of energy from your grow lights. Although watts and lumens are working hand in hand, they are still different from each other.

For instance, if you are using a High-Pressure Sodium Grow Light with 1,000 watts, you can expect that it can produce 107,000 lumens. In other words, to be able to determine how many lumens for seedlings you need to use for your indoor lighting, you have to determine the size of your indoor grow area, how much is your budget that you are willing to spend, and how many cannabis plants that you have in your grow room.

So let us discuss these factors for us to get the exact lumens that you need to give to your lighting system.

Size and Type of Light of Grow Area

Let us say that your grow room has a square footage of 3X3 (width x depth). You have to multiply the width and depth to get the square feet of your to grow room. So for this example, the square feet of your grow room is equivalent to 9 square feet.

So now that you have determined the size of your grow area, you need to know the lumens per square foot of your grow area. To do this, you need to determine the amount of light first to know how many lumens it can produce. Then after that, you have to divide the lumens to your square feet.

But before we proceed on that, you need to know that cannabis plants need at least 2500 lumens per square foot. And if it lessens, expect that your cannabis will not grow effectively since your light needs more energy to give your cannabis more buds.

And since we are aiming to copy the effects of the sun on cannabis plants, we need to target 10,000 lumens per square foot since this is the exact lumens that our sun can produce.

But this would vary according to your budget. If you are working on your budget, then 5,000 lumens per square feet is already enough rather than to go for the 10,000 lumens per square feet. But then again if you want to provide the best growing environment for your indoor cannabis plants, then go for the 10,000 lumens.

So let’s target the 10,000 lumens by multiplying it to the square feet of your grow area which is 9. So 10,000X9=90,000 lumens, if divided you will divide your lumens to the total square feet of your grow area you will get 10,000 lumens. That means you have targeted the ideal growing environment for your cannabis.

After knowing the lumens that you need, you have to look for a grow light that can produce 90,000 lumens. And the best watts to use for you to get at least 90,000 lumens is to go for 600 watts grow lights.

But since grow lights come in different types, you need to pick the best grow light that is close to your required lumens. So if you opt for HID grow lights with 600W, you can expect 85,000 lumens. For HPS grow lights, it can produce 89,000 lumens, and for MH grow light, there are 55,000 lumens.

So the closest grow light that can reach your target is the HPS grow light since 89,000 lumens divided by your square feet which is 9 is equivalent to 9,888 lumens (HPS (89,000) / square area (9) = 9,888).

Plants Per Square Foot

If you have a 3X3 growing area, it is ideal to put 6 to 9 cannabis plants. However, this will depend on your strain. If you are growing a Sativa plant (large one), you need to provide a 9 square feet growing space to avoid complications. And if you are growing Indica strains (short ones), you can add 12 cannabis plants into your 9 square feet growing space.

When it comes to wattage, you need to use 50 watts to 80 watts per square foot to reach the ideal or optimal wattage requirement. But if you are using weak grow lights that provide the lesser light amount, you need to give a minimum of 30 watts per square foot for HID grow lights and 150 watts per square foot if you are using incandescent lights.

All in all, you always need to determine the type of grow light that you will use to get the exact watts and lumens that you will apply for your certain grow area size. And of course, you need to consider your budget as well to get a win-win situation. So do the computation now and find out how many lumens you need to your current growing area and hours each day!