Huh? Lights, soil? I do not comprehend

[wordwiz]

Now I am tee-totally confused. I do not know if I am doing something so right it has never been done before or the opposite.

Example One:

Taken yesterday

Taken Dec. 31

Look at the internodal length as well as the length between leaves.

Example Two:

This is a Tasty Jade Cucumber plant that was transplanted about six weeks ago. It's suppose to be an eight week plant which normally means ten weeks or more until fruit appears. But the vine isn't large enough to reach the top of the container yet it is setting fruit.

All three plants are under 105 watt, 5000K CFL bulbs, made by Eiko. The tomato has one to itself, the cukes are sharing one.

My first thought is that the bulbs emits zero amount of far-red light - that's the spectrum that tells the plant to grow taller. But so does red, (not as much, though) yet the plants are not growing tall. The tom is no more than 10", the cukes are less than 8".

Plus, how does a cuke flower when it has no foliage, at least compared to what I see in a garden?

Dazed and confused, to say the least!

Mike

 

[wordwiz]

50 views, no replies? No thoughts?

I contacted Eiko and they sent the color spectrum data:

It has a noticeable amount of far-red but also violet. Could the purple be working to keep the plant stocky?

Mike

 

[Omri]

Google Pr & Pfr states.
Posted somethin' 'bout it on here before, too.

 

[wordwiz]

Omri,

If you are talking about plants using red and far-red, I have. There was article I came across a couple of days ago that talked about stored Pfr being converted back to Pr at certain temps (I think it also was in darkness) but it's not that cold upstairs! Also, someplace a person wrote about how changing the amount of light in the 380-410 nm area can increase the red/far-red ratio, though this was in an article about filters used in GH glazing.

I've contacted the expert at OH State Univ. in the area of GH lighting for veggies and hoping he can shed some light on this situation (Poor pun!)

Mike

 

[Omri]

I'd still use the search function if I were you.

 

[wordwiz]

Omri,

I did, and didn't see anything on the first two pages of Google results I had not seen before, especially nothing that explains why a bulb that has a high amount of light in about the 410 nm range, plus a noticeable amount in the 720-725 range, would result in such a pronounced "squatty" growth.

OK, in the long run, the only thing that really counts is how many pounds of tomatoes this plant produces - anything else is fodder for discussion! But I am still curious why this plant is growing the way it is.

Mike

 

[Omri]

Did the search for ya:

There's a mechanism in plants called Phytochrome. the Phytochrome is basically a form of pigment sensitive to two types of red - 660nm~ and 730nm~. The Phytochrome's main role in chiles is seperating natual shades from ones caused by other plants. in Photosynthesis most of the close red light (660nm~) is absorbed, while the distant red light (730nm~) usually stays the same. when the ratio is low (0.01/0.8), the plant "knows" another plant is covering it. this tells the plant to put all of its energy in growing up. meaning a thin, tall and minimal growth, with the goal of reaching the sun. when the ratio is high the growth should be normal, but when the distant light is relativelly missing, it may cause a bulky growth.

Yours seem quite healthy, but I'd keep an eye on it.

 

[wordwiz]

Omri,

Thanks, but I knew this part. In the case of the bulb, it emits a significant amount of far red (way more than my HPS bulb) but, something is counteracting that. My guess is cooler temps play some part and the higher level of violet light may be a significant factor also. A couple of papers have said that a high Daily Light Integral (>18 mols) combined with cooler temps promote more lateral shoots, more - but smaller and thicker - leaves while not increasing height at the same rate. That pretty much describes my situation and plant.

Mike

 

[wordwiz]

The combination of plant, soil, light, heat and ferts and how it is growing continues to baffle me. We did have much cooler temps this week, but I also gave it an inch of water with fertilizer in it (Tomato-tone with extra Nitrogen via Fish Emulsion - 2400 ppm) last Sunday. Not much vertical growth this week, but the foliage gets thicker and thicker and the leaves are a beautiful green.

This is from 2-3 inches below the canopy where I would expect some distance between nodes and leaves. After 36 days it is still only 14" tall.

Mike