Some help with special PPFD

Hello and thanks for reading, Does anyone knows which one is the best ppfd for the slvia divinorum? looking for maximun vegetative growth...not rooting of clones.
Or maybe how many watts of a good cob like an actual vero29 per square foot are needed?
I assume that a good spectrum would be around 5000-4000 K...but not sure only common sense.
I dont know if I am posting this in the correct forum...sorry if I did a mistake ...but ppfd is a term that most people here know better than in other forums...
My guess is about 150-250 ppfd...

I would look towards 5700k for vegging helps keep the stretch down and generate secondary growth. Regarding ppfd I would aim for 25w/sf/m for veg max and 35-50w/sf/m range with 3500k 80cri for bloom to keep stretch down some more

High K values aren't necessary for a good veg spectrum. Plants require 5-6% blue light to satisfy the functional aspects, primarily to avoid abnormal growth and facilitate stomata function. Vertical growth can be kept in check with up to around 25% blue after which point it's not going to make much difference. The law of diminishing returns will also apply in that range so I think anywhere between 10-15% blue is ideal. The reason higher levels of blue aren't desirable is that red photons are more likely to be absorbed and consume less energy being produced, meaning that a watt of light with more red will have more photons and they're more likely to produce a synthetic reaction.

What this indicates is that 3000K is a fine color temp for veg. Restricting the deep red and far red (by using a lower CRI) can help tone down stretch without sacrificing spectrum efficiency, so a dedicated veg light might be 3000-4000K and 70-80 CRI (for LED sources), leaning toward lower K, higher CRI if vertical space isn't an issue.

As far as PPFD, if you're looking to max the veg growth, more is better up to a point. 450-500 PPFD will produce noticeable faster growth than 150-250 PPFD. Depending on how a person is growing a speedy veg may not be that important though. If one is looking to maintain plants for cuttings 250-300 PPFD will be fine. If one is trying to bulk plants up quickly to be transferred to a flowering chamber 450-600 is much better... but there again, if the flower cycle is 2+ months a fast veg rate may not be critical depending on the ratio of veg/flower space being used.

Thanks for the responses..but I think you are talking about cannabis...I was asking about salvia divinorun ppfd... this plants needs less light,,,,I am looking for the maximun light it can handle with vigorous growth....

Yea, sorry about that. It grows in shade... I could take some par readings in the shade tomorrow and see what the meter says.

Rahz said:

Yea, sorry about that. It grows in shade... I could take some par readings in the shade tomorrow and see what the meter says.

Click to expand...

Thanks.

Raining and overcast today, tomorrow as well. I should be able to get some good readings on Saturday.

I can wait Thanks

Sun came out. I took measurements in various locations.

Full sunlight: around 1850-1900
Open area shaded by tree with no low branches: 350
Shaded side of house: 70
Under heavily wooded area: 25-35
Base of a thick bush which was shielded from direct sunlight: 7

I couldn't find anything in the 150-300 range. Entering most shaded areas dropped the PPFD down below 100. It was only in the open shaded areas where there was plenty of reflected light that the meter would jump above 100.

Indoors: I observed a range from 3-12 with lights on and some sunlight making it's way through blinds. A kitchen area with no blinds and no direct sunlight registered 7 and then 12 when the ceiling light was turned on.

Thank you very much for taking the effort and time. Your information will help me a lot. Amazing the potency of sun....I was today here (high Pyrenees) ...this pic is for you Rahz.

10-150 for low energy plants.