How Much Weed Can A 1000 Watt Light Produce?

When starting out growing weed, you’ll have a lot of questions about grow lights.

Everyone wants to know how much bud they’re going to have in their hands after all their hard work, so a common question is “how much weed can a 1000 watt light produce?”

I’m going to do my best to answer it in this article.

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How Much Weed Can A 1000 Watt Light Produce?

Short answer: Sadly, there is no simple answer to this question. The yield you get from a plant under a 1000w grow light will vary based on a variety of factors such as your skill level, experience, the strain, growing techniques, and the quality of light you’re using.

However, if you’re looking for a rough idea using wattage, you can estimate 0.5 to 1 grams per watt, with 0.5 grams being considered a good yield, and 1 gram per watt would be considered an excellent yield. Therefore, under a 1000w watt, you can expect to get between 500 – 1000 grams ( or 17 – 35 ounces )

However, these yields will be hard to achieve without the right growing conditions.

Factors That Will Affect Your Yield

Although I’ve provided you with a rough idea of how much weed you can expect per watt from your 1000w grow light, It’s important to keep in mind that lighting can only do so much.  There are many factors that are important in determining the yield you get. Let’s take a look at the most important ones.

Skills & Experience of Grower

Following a good growing guide will help, but ultimately the experience and skills of the grower will have a big effect on the yield you get under a 1000w grow light. Just like driving, you can learn all the theory you like, but you won’t start properly learning until you get in the car. Growers who have been through a few harvests will generally produce more weed as they will have refined their timings and techniques.


Lighting is essential to producing a high highest possible yield. If you want a higher than average yield, it’s important that you choose a good quality grow light.

For maximum yields, choose a grow light that outputs a high amount of PAR ( Photosynthetic Active Radiation ) which are the light wavelengths that your plant actually uses to grow. Most good grow light manufacturers provide a chart with the PAR values at various heights. here’s what you should look for:

Vegetative stage – PAR value of 400-600 at 24″
Flowering stage – PAR value of 600 – 700 at 18″

In general, lights with higher wattage should have higher PAR, but that’s not always true.  You can buy an inexpensive 1000 watt HPS that actually has a LOWER PAR value than a high-quality 600w LED.  When shopping for a grow light, it’s more important to know the PAR value than wattage.. if a manufacturer doesn’t disclose the PAR information for their light, reach out and ask!


If you’re looking for large yields, you’ll want to choose a strain known for its large yield genetics.

It’s a good idea to avoid auto flower strains if you’re hoping for large yields.  Auto-flowers usually produce smaller yields than Indica or Sativa strains due to the fact they are mixed with nonflowering Ruderalis strains for their auto-flowering qualities.

Grow Space

Your grow space will have a big impact on your yields. To improve your yields, make sure your grow space has the following:

  • No light leaks
  • Plenty of space for your plant to grow into.
  • Mylar reflective surfaces
  • Good air circulation
  • Correct temperature

To ensure your plant is grown in the perfect conditions, you should invest in solid marijuana grow tent.


Low-Stress Training

Low-Stress Training, or LST, is a tool that many new growers don’t know about, but it’s an excellent way to increase your plant’s yields.  Essentially, LST is like an exercise program for your plant… it helps increase the ability for the plant to grow more buds.

There are a few kinds of LST, some of which are more complex than others. Topping can increase your yields by up to 150%, while scrogging or manifolding can double your plant’s yield.

It should be noted, however, that any kind of training places stress on a plant and can have negative results if done incorrectly. Growers who plan to use these tools should research thoroughly and be prepared for setbacks while they learn the techniques.


In general, a light with higher wattage should produce a higher PAR value and, therefore, a better yield.  A 1000 watt light, on average, will produce more than its 500-watt counterpart.  As a basic rule of thumb, you can use the tried-and-true baseline of .5 to 1 gram per watt of light.

However, “how much weed can a 1000 watt light produce?” is really the wrong question to be asking. There are far better ways to maximize your yields and many other variables that should be considered.  If you’re looking to ensure that you get the most bud for your buck, we recommend considering all aspects of your growth… including your grow space, lighting, container, and training methods.

What do you think? Have any tips or tricks that have worked to increase your yields?  If so, let us know in the comments… and, as always, thanks for reading!

James Alexander James Alexander
Hey, I'm James! The founder and head writer here at I started this site to share my passion and knowledge of all things cannabis. I used to work as a budtender in central Amsterdam, and have over 7 years of growing experience.

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