how many plants under 150w, 600w, 1000w hps

How Many Plants Under 150w, 600w, 1000w HPS? Explained!

Growing cannabis plants can be tough, especially when the wattages vary. However, not all grow lights are perfect for every condition. Even more so, there are tons of different conjectures of using a certain amount of plants.

So, how many plants under 150w, 600w, 1000w hps?

For a 150w light covering a 2’X2’ area, you can go mostly up to 2 plants. Because 150w is not that efficient to cover a large area. For a 600w HPS light covering a 4’X4’ area, you can grow around 8 plants. Lastly, 1000w HPS light is the most powerful of the many with 13-14 plant coverage.

Now, there are many different factors to consider before you choose the HPS lights. So, let’s try to go through those for more clarity.

How Much Light Do You Need?

The thing about HPS growing lights is that they are quite inefficient. All HPS lights are very old relics where almost 60% of the energy gets lost. Also, you don’t even get that much of a performance boost compared to other lighting systems. 

So, why is HPS light still used?

The reason is that growers tend to like these types of lights for some reasons. Growers believe Halide lights can provide better yield. On top of that, HPS lights can offer a natural warm light spread for the plants.

With that said, what ideal lights should you use? 

Well, the quantity of light is not the main factor. The most important determinator is the light footprint. As mentioned before, HPS lights tend to have a weaker energy production. 

So, you need to use more HPS lights compared to LED lights.

However, depending on the growing stage, the lights can heavily influence the yield. The same goes for different types of LED or HPS boards. There’s a clear difference between qb288 and qb304 LED boards as well.

So, just like the boards, the HPS wattage can yield very different results.

Does Higher Wattage Mean More Yield?

Many growers think that higher wattage results in more yield. But is that the real scenario? Or is it just a myth? Let’s find out about that.

The answer to the question is no, the higher wattage does not ensure more yield. Because if your grow tent does not have enough space, more wattage can be counterproductive. 

Look at these grow tent situations where all the pots are quite cramped-

1000w HPS grow light
Source: growweedeasy.com

While this setup is still okay, you don’t put too many plants under one grow light. The rule of thumb for growing lights is to plant 8 plants under one. However, only for the 1000w HPS grow light, you can exceed the limit.

Now, what happens if you put too many plants under one grow light?

Your plants won’t get enough light footprint. For any HPS light, the ideal light footprint is around 75W per plant. So, if you’ve exceeded the limit, I would suggest adjusting the lighting to bring more lights.

So, higher wattage can only provide a better yield if the light footprint is good.

How Many Plants Under 150W Bulbs?

Now, it’s time to discuss all the intricacies of a 150w HPS bulb or light setup. A regular 150W HPS light can cover up to 2’X2’ or 60 square cm space. If you’re using a 2’X2’ grow tent, then you can grow 2 plants easily. 

As mentioned before, the general rule of thumb is to allow 75W per plant. 

So, 150W/75W = 2 plants

That’s how you can calculate the ideal plant amount for your 150W HPS light.

150W light is perfect if you are just starting out. However, it can be hard to find good HPS lights to use. Because there are many inefficient grow lights out there.

I’ve personally used Hydroplanet Grow Light Fixture HPS 150W on my 2×2 grow tent. These are quite good and offer a relatively fair price.

Many growers use Sun System 150W Grow Light due to its portability and 2 years warranty. So, you can easily change it if the light stops working.

Also, High Yield Lighting FloraLux 150-Watt is another good contender in the budget segment.

Getting these lights will never be a bad decision for you! Now, if you want to check out the scenario of 600w HPS, go to the next segment.

How Many Plants Under 600w HPS?

600W HPS is more powerful than 150W for obvious reasons. Because of its prowess, it can cover a larger area than 150W HPS.

So, how much area does a 600-watt HPS grow light cover?

600W HPS can cover up to 4’x4’ area or 120 square centimeters. That’s exactly twice the size the 150W area can cover. On top of that, the average yield can go up to 10 oz in some cases.

Going back to the rule of thumb, 600/75 = 8 plants.

how many plants under 2 600w hps
Source: 420magazine.com

If you want to know how many plants under 2 600w hps, just double the plants. Hence, 16 plants light footprint can be covered by 2 600w HPS. 

However, using 2 plants under 600w is a bit overkill. Because 2 plants 600w yield is the same as 2 plants under 150w.

So, if you’re using a 4×4 grow tent, then 8 plants should be the ideal scenario. 

Now, are you thinking of going a bit farther to get 600w HPS lights? If so, there are some good products to choose from-

Even these typical HPS grow lights can influence the swelling of calyxes as well. So, if your cannabis calyxes are not swelling, your light footprint is not enough!

How Many Plants Per 1000 Watt HPS Light?

So, we’ve come to the very last topic for discussion. 1000w HPS is the highest-powered HPS for general consumption. Also, there are very few reasons to go up from 1000w.

Now, generally, 1000w HPS can cover up to 5’x5’ or 150 square centimeter area. That’s not a lot if you compare it to 600w HPS light. 

However, the ideal plants under this type of light are 13-14. However, it’s best to stay under 10 plants because of the light footprint.

Look how brilliantly blue window seed grows within 8 weeks under 1000 watt grow light-

If you’re planning for the most coverage, then 1000w HPS is the one. 

That’s everything on the plants’ amount and area coverage of these HPS lights. I don’t think you’ll have any problem deciding your preferred one anymore!

Frequently Asked Questions (FAQs)

How Many Plants Can I Grow in a 4X4 Grow Tent?

The most optimal plant amount for a 4X4 grow tent is 9 plants. Growers usually calculate the plant spacing with the total area. So, if you plan to use 9 plants in a 4X4 grow tent, then you’ll get one square foot for each plant. That’s more than enough to get a good amount of nutrition and sunlight.

How far should 1000 Watt HPS be from plants?

Because of the 1000w light’s power, you need to keep it at least 15 inches. If you were to calculate it in centimeters then it would be 38. But, if you can adjust the light a bit, a distance of 30 inches also works. But don’t go anywhere less than 76 cm as it would be inefficient for your plants.

Can a Grow Light Burn a Plant?

No, there’s very little possibility of growing light burning down the whole cannabis plant. Because in overpowering grow light, the plant won’t catch fire as it uses light to grow. But, your plants can be less productive because of the excessive light. So, be careful about the lighting at all times.

Concluding Remarks

Now you know how many plants under 150w, 600w, 1000w HPS light you should plant. However, always remember to change the light position and light intensity according to growth stages.

So, be persistent and get an awesome yield at the end of the season!

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