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how many watts to grow indoor weed

How many watts to grow indoor weed

Fluorescent grow lights come in many different shapes and sizes, from twisty bulbs to long tubes. Fluorescents are popular because they make efficient and pleasant lighting for humans, and also work great for herb gardens and other types of low-key indoor gardening without using a lot of electricity.

T5 grow lights are one of the most easily available types of grow lights and are used to grow many different types of plants. As a result, they’re available in many garden and home improvement stores.

There are lots of options for grow lights that work well for growing cannabis indoors but in the end they boil down to 3 major types:

How many watts to grow indoor weed

The highest-yielding types of grow lights are HPS, LEDs, and LECs. HPS consistently gets incredible yields, especially in the 600W size which is the most efficient. LEDs give you a much bigger range of results. The worst LEDs get only a fraction of the yields you’d get with an equivalent wattage HPS. But some LEDs like the Electric Sky 300 seem to consistently beat HPS when it comes to yields per watt. LEC grow lights tend to get similar yields as HPS or a little more.

One gram per watt is meant to be a sort of “upper limit” of what to expect from indoor grow lights as far as yields. Although it’s possible to get even better yields (certain LED grow lights combined with the right skills can produce 2 grams/watt and beyond), even getting close requires preparation and a good setup. Most people are not going to put in the time, effort, or money for this and that’s okay.

After – Notice how all the bud sites are now exposed, and the light can get to bud sites deeper down into the plant.

These tips may seem simple, but if you follow them all they will make a huge difference.

Example of Light Hours

My Critical Purple Kush yields and bud quality have been excellent. Here are two Critical Purple Kush plants grown in different tents. No matter how big the plant, the strain fills the branches with buds. (though just as a warning my buds didn’t turn purple, though they usually do especially if they get cold nights near harvest)

Before – Notice how leafy these plants are; no light can get down past the top canopy and the floor is in shadow. Way-too-bushy plants like this are prime candidates for defoliation

Put the effort into making a great growing environment. This causes plants grow much faster and healthier than in sub-optimal conditions.

As a cannabis grower, you may have come across this term: “1 Gram/Watt”

How many watts to grow indoor weed

Instead of looking at how much wattage a grow light uses, it’s far more important to understand the grow light spectrum, which is measured in micromoles (?mol). You need anywhere from 180 to 1300 ?mol to grow plants with grow lights, depending on how light hungry your plants are. The Cannabaceae family of plants are on the higher end of the spectrum: they need 800 ?mol to grow up to 85% of their natural potential, or 1300 ?mol to grow to 100% of their natural potential. Kitchen herbs,salads and other leave plants on the other hand only need 180-380 ?mol.

A lot of people believe that you need a 1000 watt artificial light to grow hemp indoors. The reality is, you can successfully grow medicinal herbs with far less wattage, saving you money on your electricity bill while growing healthier plants. So, how much wattage do you really need to grow indoors?

Yes. Much like a human sunburn, your plants can burn or bleach if you use too much light.

Wattage is a measurement of electricity consumption, and while it’s helpful to know how much wattage your grow light uses (so you can make a more economical, energy-saving choice) it actually has nothing to do with the amount of energy your plants need to grow.

How much wattage do you need to grow indoors?

Those 400W are also giving you a fairly narrow grow light spectrum, so your plants end up not getting the amount of proper light they need.

The idea that we need 1000 watts to grow hemp comes from the days when it was common to use High Pressure Sodium (HPS) lights to grow anything indoors. At the time, HPS lights were the only decent artificial light source on the market, and a 1000 watt light was necessary for a sufficient photosynthetic light spectrum.

You can use a PAR meter to determine your grow light’s intensity in ?mol for light spectrum between 400-700 nanometers (nm) – in other words, for any light spectrum that’s suitable for growing plants.

Do you need 1000W to grow indoors? Not with LED Habitats Grow Lights

The simple answer is: it’s not really about wattage.

Let’s take a look at this short day plants-growing myth, and how you can grow indoors with eco-friendly (and wallet-friendly) LED grow lights.