All my weed is amazing! I would, of course, be disappointed with an 18g plant. I
can count to 28 -- and beyond. Nevertheless, I let the small plants finish. They're often excellent, potency-wise, and I wonder why.
I haven't been thinking of growing efficiency in terms of grams per watt. Another efficiency measure is yield per area, which I believe may be better.
- Wattage used emphasizes one growth factor over all others. Lights are not created equally, so one light's wattage may not be comparable to another light's wattage. Further, wattage only applies within the range of a plant's tolerance. It is also a counterintuitive negative correlation: Raising the wattage mathematically decreases efficiency, while decreasing the wattage does the opposite.
- Area uses standard units of measurement and thus cannot be changed. A square foot of tent space is always a square foot of tent space. All growth factors, therefore, impact the efficiency ratio.
Admittedly, I have long been a skeptic of high-powered lights. I appreciate advancements in light technology, but I'm also leery of marketing hype. I put wattage meters on my lights, and I've never used the full rated power of any light. None of my lights are rated higher than 30 watts per square foot.
I spent time thinking and writing about this because you asked. (It's also how I learn.) My focus has been on growing enough for our needs and the basic pleasure of growing these plants. For me, this isn't an occupation. It's a hobby. I respect other growers' methods, even if they differ from mine (as most do).
And yes... I recently won a 640-watt light. It's much more powerful than any light I've used so far. I promised Phlizon I'd provide a thread about it, and I will. My opinions might change. If they do, I'll write about it in that thread. The light has shipped, but I don't have it yet. I'm eager to get started, but the chaos in the only room where I can put it is challenging, to say the least. I'm also thinking about what equipment to buy to go with it.