Height at 4 wks

[rupert]

I'm growing 6 plants in a cabinet and they are now 29 days from seed. Five of my plants are about 4.5 inches tall, and one is about 8 inches tall.

Is 4.5 inches a bit short for 29 days, or normal? These plants have about 5 nodes each.

Not sure why one is so much taller than the rest.

My team:
2 crystals
3 PPPs
1 mystery plant

The tall one is a PPP. I wonder if maybe it's not actually a PPP, or maybe is a male. It's supposed to be a feminized seed, though. It's not as bushy as the other 2 PPP plants.

This is my first grow. I'm growing in 4-gallon containers in coco with a little perlite. LED light.

Thoughts? Thanks!

 

[SolMJ]

all depends on the strain buddy, sativa's grow taller for example. But I think 5 nodes at this stage is alright, are they looking healthy & are your lights as close as can be?

 

[rupert]

thanks. I don't know if my light is close enough. I think I had it up too high. Then again, people say that if your light is too high, it will cause plants to stretch and get leggier, but 5 of mine are short and bushy.

In any case I decided to lower it down from around 28" high down to about 18" high. The light is a Platinum LED 300p and I have it on full power. I think it's supposed to be roughly the equivalent of a 300 watt HID. On the web, people recommend everything from 30" high to 8" high. The manufacturer suggests 18" high.

 

[SolMJ]

Put your hands over the canopy & if its too hot for you then its too hot for the plants...thats how you'll get them as close as possibe.

 

[rupert]

It's an LED light, so I can actually touch my hand directly to the glass on the underside of the light, and it's not too hot.

I suspect there may be other reasons why it's not a good idea to have plants too close to the light. Each LED seems to put out a different color, at least it looks that way to my eye. So I'm wondering if the plants have to be far enough away for those colors to blend properly.

The other reason to raise up the light is that it increases coverage. Hard to gauge the trade-off between intensity and coverage without a light meter.

Thx

 

[SolMJ]

Sounds like you could be right but I don't about led's...you should do some research online & get it right because eventually you'll want the light to reach the lower parts of the plants. Get yourself a lux meter, not expensive at all & really handy.

 

[rupert]

Yeah, true. I ordered a lux meter just now. 19.99 from amazon. Thx

 

[Dave Groomer]

Yeah, true. I ordered a lux meter just now. 19.99 from amazon. Thx

You can download an app for your smart phone too that does a reasonable job. Also you are right about the "blending" of the spectrums. I don't get my LEDs much closer then 12 or 14" because you start to loose the overall light and can start seeing individual led colors on the leaves. During veg, I keep them 18-24" depending on how old the plants are. As the get older I move the lights closer.

 

[rupert]

Thanks! I take this as a vote for 18 - 24" since I'm still in veg. That's kinda what I wanted to hear because coverage in my cabinet is not great (just going by the naked eye) if I lower the light down below around 20". Maybe during flower I'll add a couple CFLs.

I'll have a lux meter in the mail on Thursday.

 

[jojo677]

I'll agree with supergroomer. I've had the best luck with the manufacturer's recommendations. I use a 300W (185W actual) draw LED, and veg at ~18" (or more for smaller plants) and flower at 12". Even then I get some of the spectrum breakup mentioned above.

 

[AKgramma]

As a reply to the initial post: My first grow is from seed (Purple Mazar), and I am 78 days in, with 3 of them having been under 12/12 for 31 days. I had one in veg suddenly preflower female, and so she joined her sisters a couple days ago. I used ordinary garden fertilizer once or twice in veg, bloom feed once in flower, then went totally with sugar-water for each feeding for everyone. Oh, and growing only under common CFLs in 2 closets. Really simple, as cheap as I could manage.

What I experienced was a wide variety of phenotypes, from short and very bushy to tall and lanky. After sending the males to the edibles bin, I ended up with 4 females and 2 undetermined in veg, all but one 24" tall, including planter.

I also notice that, even though one flowered earlier than the others, the slower ones are rapidly catching up, probably due to being larger and stronger before flowering. And unexpectedly, one decided to start flowering while under 18/6 on her own. Yet, these are not autoflowers, but specifically labelled as photoperiod.

The point of all this is that you are going to get genetic variation from seed. Clone your best ladies for your next crop, and you will gain a couple weeks or more head-start. Once clones root, they grow wildly under 18/6!

 

[NateToke]

It's early in your grow, but a 300W platinum is not enough for 5 plants. It's plenty for now, but you'll want more juice by flower time. I started with one P300 and now have two P300's, one P600, and a Mars II hydro 600W. I much prefer the Platinum's to the Mars.

 

[rupert]

AKgramma, I've also noticed that the best growing plant today is not the best one 3 or 4 days later, in many cases. They do trade places.

NateToke, I suspect you are right. Though I think a 450p would probably be enough for my space.

Now that I have a lux meter, here are some of my findings.

 

[rupert]

Also, I can't believe I started this thread just a few days ago. My shortest plant is now 6" tall. The tallest has gone from 8.5 to 9". All look quite healthy, with lots of leaves. At times I've fretted about having too much density of leaves, but then the nodes spread out a bit and they no longer look too dense. I'd say I have no real problems at this point despite messing up ph a little at times.

 

[Victo]

Nate Toke,
Why do you prefer the Platinums over the Mars? Is it performance of the light spectrum or is it things such as quality. I use mars now but I'm looking to get another LED light and all I've owned is mars brand so I have nothing to compare to. Thanks Buddy!

 

[NateToke]

There is absolutely nothing wrong with Mars, and nothing better at that price point, but my Mars 600 puts out substantially more heat than my P300's combined or my P600 by itself.

I also believe that Platinum covers a wider spectrum than Mars. The Mars light is noticeably whiter than the purplish Platinums. I won't even pretend to understand light spectrums and how the plant uses them. Some say the extra wavelengths on the Platinums are not used by the plants, but until I do a dude by side controlled grow with Mars v Platinum I will not have any personal knowledge. I'm sure it's been done, I've just never gone looking for it.

I have two tents because I originally planned on a perpetual grow, but when I realized I was growing far more pot than I could use (and hate giving it away because everyone wants to know where I get it), I scaled my plans way back and only grow 4 autos at a time these days. This let me play with my light configuration and try to drop my tent temps.

I tried a number of combinations of the four lights and the 3 Platinums running at the same time kept my text 5F cooler than the two P300's and the Mars. That said, I live in a warm environment and struggle to keep my tent in the low 80's. Not looking forward to July & August heat, but I think I can fight that with better external air draw from a cooler part of the house.

 

[Victo]

Thanks for the detailed answer! Running hot was an issue for me as I had to turn my central AC on way earlier and at a lower stepping than normal. I piked up 10 degrees over my house ambient temp. I thought that was a small temp increase for all the light they were providing but I had nothing to compare it to. I think I will try a platinum 600 for my next light as I've never seen a bad review. I was also thinking of getting a 4 in 1 heat/ac unit as the temp swings really kicked my butt!