change in light spectrum (to red) triggered flowering.

[Iamnumber]

Hi,

I am now bit confused about how plats are triggered to flowering. I do have a fair grasp about photo periods. I do have academic knowledge how 'far red' light can affect photo periodic requirements.

Now.. dose the introduction of red light ( 620~630nm, 650~660nm) trigger flowering IF plant is used to only blue (veg) light ? Photo period remains untouched (20/8)

From veg light to stronger light (double) of veg and flower spectrum.

I did not consider such change could trigger stress. Start of flowering is clear and evident change. Plats that "should be female" have flowered as males after such stress.

Two separate incident.
One was Fem seed > started flowering as male after only 2-3 week veg.
One was under longer veg. I (perhaps incorrectly) determined that plant is female from pre-flower.

It would be nice to hear if I have managed to totally miss some key information or if I am walking into uncharted territory?

PS
As corrective action the plants are now 24/0 under fluorescent light. Male will be culled and used for experiments.

 

[Phaeton]

When I did side by sides using Platinum brand I encountered almost pure red. The ratio was close to 90% red and the plants suffered from it. Not enough energy for proper growth and leaves began to yellow quite early.
The plants did not go into flower mode, they just yellowed the fan leaves from the red. The dark period is still required for Florigen production, Far Red can cut back the dark time needed, but not to under eight hours. If the light cycle is on the edge then spectrum can make it tip one way or the other. 18/6 will not ever bud the plants.

I am assuming by 'blue' light you mean blue weighted full spectrum and the same for red. Side by side testing also showed 90% blue was quite ineffective for growth, worse even than the pure red. HPS gets way with bad spectrum by having copious quantities of orange and green, strong chlorophyll feed wavelengths, and just enough of a trace of blue so the plants still flower, albeit slower than normal.

Pardon the pun, but I am still in the dark about the lights and timing of the lights being used.

 

[Iamnumber]

Thank you for the info and sorry about inaccurate terminology.

The 1st light used was grow led with both veg and bloom dials. As it was veg period the bloom dial was set to 0%. Veg spectrum includes (more than I actually remembered) red.. to naked eye light looks 'cool white'

Plants were happy and no adverse signs were present.

As this was needed elsewhere replacement was led grow light without any dials or switches - Blasting both veg and bloom spectrum. (Hence I used the term .. introduction of red spectrum / bloom light).

So from heavy on blue (perhaps ~75/25 blue/red ratio?) with some red to a light which was roughly 50/50 on blue/ red ratio. to naked eye this looked very violet.

specific products were:
LeoLed iSpectrun (1st light) and MarsHydro 300w led (2nd light). (few years old- 3 small fans for air)

The wattage used did increase (but later light was used on larger area (=raised bit higher) )


As for why the 'weird' light cycle.. I wished to give 'good and safe' 6h dark period and ended up with 20/8 instead of more standard 18/6.

To find the sense of exploration and discovery it is good to stray from the beaten path. .. and now we try to figure out just what the heck caused the difference "what I/we expected" and "what actually happened"