Light Intensity During the Last Week of Flower

Greetings, green thumbs! We all know I’ve had my fair share of growing room escapades.  One moment, I’m battling with flickering lights in a newly constructed grow room.  Next, I’m making warranty claims for defective lights with 600 eager plants just begging for some sun!  “Should’ve put that in my first post,” you might say. …

Light Intensity During the Last Week of Flower

Understanding the Importance of Light Intensity

Understanding the Importance of Light Intensity

You’ve heard the tales. I sure have. 

Cannabis plants pack on weight towards the end of flowering, just like me, after the holidays. 

Light is the not-so-secret ingredient behind this miraculous transformation. 

You see, light is to plants what the disco ball is to John Travolta in Saturday Night Fever – it makes everything dance!

Bud development, resin production, and overall flower quality – all these factors boogie under the disco light of your grow room.

We’re talking about a sizable yield of ~110-115g per plant dried and cured or, as I like to put it, 1.7ish lbs wet, ready for processors. 

Now, that’s a lot of boogie!

Light Intensity Adjustments in the Flowering Stage

Light intensity during flowering? 

Well, that’s kind of like telling ghost stories around the campfire. 

You start low, crank up the fright as you go, then taper off at the end to ensure everyone gets a good night’s sleep.

We’ve seen it in the field, starting with 300-watt lights in the veg room, increasing to 600 watts as the flowers begin to show, and pumping the intensity up to 900-1100 watts between Week 3 and Week 6. 

After that, it’s time to cool down, just like we do after a particularly intense dance-off.

The Significance of the Last Week of Flower

The Significance of the Last Week of Flower

In the thrilling world of cannabis cultivation, the last week of the flowering stage is like the season finale – the crescendo of an orchestral masterpiece, the final reel of a blockbuster movie. 

Here, light intensity plays a crucial role in ripening the buds and maximizing resin production. 

It’s the swan song that ensures your buds are ripe and ready for the final curtain call.

You know how I love my seasons. 

Like fall signals the end of summer’s warmth and the beginning of cooler temperatures, lowering light intensity in the last week of flower mimics this seasonal transition

And just as we bundle up for fall, cannabis plants respond to this change by increasing resin production, protecting the precious terpenes and cannabinoids from light depletion.

Factors to Consider in Adjusting Light Intensity

When it comes to adjusting light intensity during the last week of flower, here’s what you need to know:

  • Gradual Decrease: Plants are like us after a Netflix binge – they don’t appreciate sudden changes. When lowering light intensity, it’s best to do it gradually, mimicking the slow transition from summer to fall.
  • Strain-specific Factors: Much like my cousin Joe reacts differently to horror films than I do, different strains respond differently to light intensity adjustments.
  • Temperature Control: Remember my mention of “not vaporizing my terps”? Well, many terpenes vaporize around 70° F, so keeping the temperature in check is crucial.
  • Observation and Adjustments: Stay vigilant, my friends. Each plant will react uniquely to changing light conditions. Watch out for signs of stress or happiness and adjust accordingly.

Anecdotes and Tips from Experienced Growers

Ah, the tales we growers have to tell. 

Once, I had only 15 lights in a room, nervously watching as my babies weathered the storm. 

As the replacement lights arrived in different shipments, I hung them, boosting the light intensity and bathing my plants in the luminous glow they craved. 

And wouldn’t you know it, my plants thrived!

I’ve heard similar stories from fellow growers. 

Some suggest replicating the bell curve intensity of natural sunlight, with gradual increases and decreases in light. 

Others swear by cycling their lighting, saying their buds puff up like excited party balloons!



My friends, as we navigate the twilight days of the flowering stage, remember to adjust your light intensity just as carefully as you would tune your favorite guitar. 

Play the right notes, and your cannabis plants will reward you with a harmonious symphony of resin-packed buds.

Remember, growing cannabis isn’t just science; it’s an art form. 

Or, as I like to say, a bit of botany, a dash of meteorology, and a lot of love!


When should you lower the light intensity of a flower?

Lower the light intensity during the final stages of flowering for better bud ripening.

What week of flower should I increase light intensity?

Typically, growers increase light intensity during the early weeks of the flowering stage, often between Week 3 and Week 6.

What happens in the last week of flowering?

The last week is crucial for bud development and optimizing resin production for higher-quality flowers.

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