Cannabis plants need an incredible amount of intense light to grow and develop properly.
Light is measured with a device called a luxometer, and this is used to measure lux = lumens / m2. For example, on a normal day sunlight is somewhere between 32,000 and 100,000 lux. Cannabis plants have different needs in regards to light depending on their phase. Clones and seedlings need between 5,000 and 7,000 lux, during the growth period they’ll need 15 – 50,000 lux and during the bloom stage this goes up to 45,000 – 65,000 lux.
Luxometers are used to measure light emitted by grow lights so that you can know when they’ve lost power and can replace them.
Grow Lights and Bulbs for Growing Cannabis
When choosing the correct lighting for your indoor grow, you’ll need to keep in mind that each type of lighting has its own pros and cons.
You’ll need to know which lights can be used for each stage or which are best for your growing method. The objective is to improve performance and the quantity of your final yield.
At La Huerta Grow Shop you’ll be able to find high quality grow lights at the best prices.
How to Choose the Best Cannabis Grow Light
When looking at our grow lights, you-ll find the following information in the descriptions:
The power of each bulb, expressed in watts, indicates electrical usage alongside the type of bulb and the strength of the ballast that you’ll need to use it.
All lights have a specific colour temperature. When it comes to cannabis plants, colour temperature directly affects their growth. The human eye can’t see it, although it’s incredibly important for plants.
Colour temperature is measured in Kelvin degrees and is abbreviated to K:
- 6000K grow lights and above are perfect for the growth period (veg).
- Colour temperatures between 2000 – 2800°K are ideal for the flowering period.
- There are also bulbs that produce 3500k that can be used during both the growth and flowering stages.
Some manufacturers classify their bulbs as veg, bloom or mixed.
What Grow Lights Should I Use Indoors?
The best types of lights for growing cannabis indoors:
Energy Saving CFL
Energy efficient lights are special fluorescent lights that have the perfect colour temperature for growing cannabis, such as CFL lights (Compact Fluorescent Light), or compact fluorescent tubes.
- They produce little heat.
- Low in price.
- Ideal for small or short grow tents.
- Ideal for maintaining mother plants and for growing seedlings and clones.
- Low in strength.
- Not recommended for areas over 1m2.
- Highly fragile, especially the CFL bulbs.
- Over the last few years they’re being taken over by LED lighting, which provides higher yields using the same electricity.
HPS Lighting (High Pressure Sodium Lighting)
- These are cheaper than other higher-performing systems.
- These are the most common indoor grow lights.
- Before LEC and LED lights these were the best lights for 1m2 grows and larger.
- Uses more electricity.
- Lets off a lot of heat.
- Higher electrical bill.
- Less lifespan than LED and LEC
HPS Double Ended (DE)
HPS DE Grow Lights are an improved version of normal HPS lights. They need a special socket and a specific type of ballast.
They might not quite reach the same level as LEC or LED systems, but compared to normal HPS lights:
- They have an optimized light spectrum.
- More than 35% available energy.
- No metal filament means no shadowing your plants.
Metal Halide (MH)
Metal Halide grow lights produce cold light, which is to say that the colour temperature is perfect for fast plant growth. They’re generally used to maintain mother plants and during the growth stage. When flowering your plants, you’ll need to switch your MH light out for a HPS light.
- Ideal for veg period.
- They use the same ballast as HPS lights, so they can be switched out.
- Cheaper than LEC and LED lights.
- They produce a lot of heat.
- They generate more electricity and increase the need for AC.
LEC/CMH lights, or Metal Ceramic Halogen lights can produce almost the same results as HPS grow lights while using almost half the power.
If a HPS lighting system can produce 0.8g per watt, LEC systems produce 1.5 – 1.8g per watt.
- Improved spectrum, emits UV-b rays that imitate sunlight.
- Produces higher rates of grams per watt.
- Higher durability than HPS lights – up to 5 – 6 grows (twice the amount as HPS)
- Only recommended for 120x120 cm grow tents and larger.
- Higher price than HPS lights.
- Less lifespan than LED lighting.
LED Grow Lights (Light Emitting Diode) produce yields of around 1.2 – 1.4g per watt.
- Does not need ballast or reflector.
- Longer life-span, 10 times more than HPS.
- Produces less heat than LEC lighting (between 3 and 6 degrees less) and much less than HPS lighting.
- Ideal for larger grows.
- Higher price than HPS lighting.
- Produces less grams per watt than LEC lights.
What’s the Best Indoor Grow Light?
- Grow Lights that fit your growing area and produce the highest yield per watt.
- Another factor to keep in mind is temperature. LEDs are the best in this category if you don’t want it too warm.
- LEC lights, if you don’t have temperature issues, produce higher yields per watt.
- If you’re using a small grow tent, you should go with an energy-efficient light or LED system.
- If you’re not worried about electric bills and you have a good air filtration and AC unit, HPS lighting is a good option.
If you don’t have the rest of the necessary equipment – reflectors ballasts etc. – we recommend having a look at our complete lighting kit section.
Our kits come fully equipped to start growing, making the most out of each device at quite a convenient price – cheaper than getting everything on its own.
If you have any questions about which grow light you should be using for your indoor cannabis grow, remember that you can always consult with our team of professionals.