Indoor tomatoes

[Doffer]

How many hours of LED light do you give seedlings to help them form flowers as quickly as possible?

[maxjohnson]

I don't know, but it depends on the intensity of your light and the spectrum. It's the more reddish spectrum and infrared that help with blooming, newer grow lights also have UV-A that is supposed to improve vigor of the plant. You can measure the light intensity with lux meter, or more accurate PAR meter (PPFD) which is too expensive for me.

From my experience, from LED lights, 20k lux or more is going to give better results for tomato, less than 10k seems not ideal. A source is saying 400-500umole/m2 (PPFD) is ideal for tomato plants. I used a PPFD to lux converter and 400 PPFD depending on what type of LED light used is around 20k lux, which is the ballpark that matches my experience. I believe it is also helpful to use LED lights with higher CRI (color rendering index), like 90 or above.

I would guess you need less time-on with higher intensity. Along with correct fertilizer that is lower in nitrogen and higher in potassium.

I've been growing microdwarf indoor for a while, and I usually set 14hrs on. But some grow lights give you their own recommendation, and different on and off length for different growth stage.

[GoDawgs]

These are Red Robins #1 and #2 (out of four with staggered starts) and the Tangerine Dream pepper.



Red Robin #1 is really loading up. #2 is just starting to put on some flower buds.



The Tangerine Dream now has three peppers and lots of flowers. Most all of the fading flowers seem to have that tiny green bulge in the bottom that will become peppers. Yay!



Red Robins #3 and little #4 (2" tall behind #3) along with a repotted oregano, parsley orphan and drying beans.

[slugworth]

I like the toothbrush and q-tip within easy reach