Do you need 1000W to grow indoors? Not with LED Habitats Grow Lights
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?
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.
Where the myth that you need 1000W to grow hemp comes from
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.
The main problem with HPS lights (and other high-intensity discharge / HID lights) is that they end up wasting up to 60% of the energy they consume solely on heat output. In other words, if you’re using a 1000W HPS light to grow indoors, only 400W of that energy is being used for plant growth – the other 600W is being wasted, draining money from your pocket.
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.
How much wattage do you need to grow indoors?
The simple answer is: it’s not really about wattage.
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.
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 (µmol). You need anywhere from 180 to 1300 µmol 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 µmol to grow up to 85% of their natural potential, or 1300 µmol to grow to 100% of their natural potential. Kitchen herbs, salads and other leave plants on the other hand only need 180-380 µmol.
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.
Can you use too much light to grow indoors?
Yes. Much like a human sunburn, your plants can burn or bleach if you use too much light.
More wattage may mean more light output, but it also means more heat output, which can lead to burned plants. If your grow light has an output that’s higher than 1300 µmol, your plants can go into what’s called photoinhibition, when plants start spending more energy on getting rid of excess light rather than growing to their fullest potential. As a result, you’ll be left with wilted, brown leaves and dying plants.
