In recent years, many growers have started to increase light intensity in their grow rooms. The goal is simple: more light = more yield in the same space.
And yes — it really works. Some commercial growers now use up to 1400 µmol/m²/s of light.
To give you an idea:
* That’s 3 times stronger than old HPS lights 10 years ago.
* And about 50% more than what most home growers use now.
But this leads to a big question: If we increase the light this much, will the quality go down?
Science Has the Answer: Two Important Studies
Recently, two big studies looked into this. Let’s look at what they found.
🇳🇱 Dutch Study
* One plant type: Critical CBD
* 3 light levels: 600 / 800 / 1000 µmol/m²/s
* Tested for: yield, cannabinoids (CBD, THC, etc.), and terpenes (smell and taste)
🇨🇦 Canadian Study
* One plant type: Stillwater
* Light levels from 200 to 1800 µmol/m²/s, slowly increased across the room
* Over 400 plants tested
* Measured using high-tech machines (chromatography, mass spectrometry)
* With added CO₂: 1200 ppm
>>>Result 1: Higher Light = Higher Yield
Both studies show the same thing: The more light you give, the more yield you get — in a straight line.
In other words: 1% more light = about 1% more dry flower
The Dutch test showed this from 600 to 1000 µmol.
The Canadian test confirmed it even up to 1800 µmol — but only when CO₂ was added.
>>>Result 2: Cannabinoids May Increase Too
In the Dutch test: CBD, THC and other cannabinoids went up 30%(from 175 mg/g to 225 mg/g)
The Canadian test saw no big change in cannabinoids — maybe because of the plant type.
Some strains make more cannabinoids under strong light, some don’t.
>>>Result 3: Smell and Taste Also Improve
Both studies looked at terpenes — the natural chemicals that give plants their smell.
Dutch test: +75% more terpenes under strong light
Canadian test: +20~30% more terpenes
That means stronger smell, better taste — not less quality, but more.
Plants Can't Take Unlimited Light
Plants can nott “eat” unlimited light.
Just like people can’t eat 10 meals a day, plants also have a “light limit”. Too much light can be harmful:
What can go wrong?
- Leaves get burned or yellow
- Heat stress slows down growth
- Smell and quality may drop
- Plants get weak or finish too early
How to Help Plants Handle More Light
If you want to increase light safely, make sure you do these 3 things:
1️⃣ Add CO₂ (around 1000–1200 ppm)
Without CO₂, strong light won’t help. Plants can only use more light if they also have more CO₂ to breathe.
2️⃣ Keep temperature and humidity in a good range
More light = more heat.
Too hot = big problems. Use fans, AC, or good airflow to keep balance.
3️⃣ Watch your plant type and health
Some strains love strong light (1000+ µmol). Others might stress out at that level. Start slow and increase step by step.
Pensieri finali
Yes, high light works, but only if: you can get the plants to tolerate it safely.
Just like fitness, how much weight you can lift depends on whether you eat enough, sleep well, and have a solid foundation.
Just remember:
Plants are not machines.
They need the right conditions — light, CO₂, temperature — to turn light into flowers.
So if you want big results, give them a full support system, not just a strong lamp.
Jayes
In qualità di responsabile del marketing digitale presso AUXGROW, Jayes unisce la passione per i sistemi idroponici e l'esperienza nelle luci di coltivazione a LED. Con esperienza pratica e profonda comprensione, Jayes ti guida attraverso il mondo della coltivazione sostenibile.
