Growth improvement w/ Fluoros?

[Guest]

Hey guys. Has anyone heard of plants vegging better under a fluoro than Metal Halide (400w). I was having problem last week with my plants no growing all that well and turning a little bit yellow. I put them under 5 days of fluoro lights when I went out of town and when I came back they almost doubled in size. (These plants are around 5 weeks old)

I was thinking that this was a good thing, so I switched back to a MH light for 2 days now and it seems that their growth has slowed yet again to about the pace it was before. Is this normal?

Any ideas? Should I switch back to fluoro's or keep with the MH?

I posted some pics. Hope they posted properly. Thanks a lot for your help and advice. The 1st two are after 5 days of fluoro and the last 2 are during 2 weeks of MH.

 

[bounty29]

How far away were the CFLs? What wattage did you use, and how many of them?




That's one of my plants 29 days from seed. I used eight 15w CFLs, less than 2" above the tops of the plants.

 

[Guest]

2 40w 4 ft CFL about 12 inches above the tops. Shouldn't mine be growing a little bit bigger than what they are?

 

[bounty29]

Get those lights as close as possible to the plants. 12 inches is way too far. You said you have 4ft lights? CFLs are the spiral lights, are you using tube lights? It doesn't make much of a difference, either way they should be almost touching the plants.

 

[Guest]

They are tube lights, but I am using Metal Halide lights right now. I just switched to the tube lights when I went out of town. I didn't think it was a good idea leaving under the MH light for 5 days w/o feeding them.

 

[bounty29]

I don't have any experience with MH lights so I'm not going pretend I know what's wrong. How far are the plants from the light? It doesn't look like that's a problem though, because they don't appear to be stretching very much. What are you feeding them? The more information there is about your setup, the more likely people will be able to help you.

 

[Guest]

The plants are 2 ft from the MH light in 12 inch pots w/ Sta-green soil. I am using Liquid Karma and Miracle Grow right now for nutes. I had them on 24 light w/ the MH and then moved back to 18/6 for a couple of days. The seeds are feminized Oasis from Dutch Passion. Temp is 70-85 thru out the day w/ humidity around 40-60%.

 

[sproutco]

Try to get the metal halide as close to the plants as possible without burning them. 15" from the tops maybe? Use your hand to judge how hot it is. Too hot slows growth and too far away slows growth.

What's up with the yellowing bottom leaves?

How are you judging how to water? Too wet slows growth.

What is the soil mix ph? Directions for testing are in my signature below. Adjusting fert water ph after mixing prevents ph surprises.

What are you feeding the plants, how often, and how strong is it? Try to be specific. You should feed weakly with every watering.

Is there dolomite lime in the soil mix for calcium and magnesium? After 5 weeks this may be running low = need a cal mag boost; apply 1/4 teaspoon of both powdered gypsum and epsom salts per gallon of water along with the regular fert if it does not contain cal/mag. Do this every third fert or every fert with no dol. lime or supplies are running low. I bet the yellow leaves go away.

Edit: I see your using miracle grow. Try 3/4 teaspoon per gallon 15-30-15 with every watering. Do add the epsom and gypsum. Get the light lower. 18/6 no 24 hour light.

I am sorry Ms. Jackson...Sproutco is for real.

 

[green_grow]

i think that the 'growth' you were seeing under the flouros was just them streeeetching in an attempt to reach the lights which were so far away . 12" is MUCH too far for flouros.

 

[sproutco]

You must spread some Reputation around before giving it to green_grow again.

 

[kokua]

I am sorry Ms. Jackson...Sproutco is for real.

lol...yeah ok, keep telling yourself that

the plants look great!!! They just stretched under the fluro's...and being gone for 5 days makes it look like they grew alot when you are used to seeing them on a daily basis you don't notice the growth as much. They look like they are getting nice sized so I would definately have them under the MH HID..