Using a 150w hps for seedlings?

I want to know how far to keep my 150w HPS off the top of the tiniest of seedlings. I am talking about for the first two weeks of their life just after they break the ground.

If you couldn't use CFL's or T5's at this stage and could only use HPS, how far off would you place the light that will give the tiniest of seedlings enough good light, but won't encourage stretch? It's the stretched I'm concerned about.

How far off that canopy would you keep that 150w HPS?

About a foot should be the furthest away id have it so just under a foot or a foot away, but you can always change the distance if something doesn't look right, post pictures

Put your hand over the seedling, and lift the light up until you cannot feel the heat. Do this when the light has been on for a bit so it's at it's full brightness...Seedlings are easy to fry within minutes!; so better to high than too low.

10-12 inc

Thanks everyone. I'm getting stretch on my cfl's which makes me think they are not the best. They claim to be 2700k but I'm not fully convinced.

I'm also trying to run 12/12 from seed so 1/2 the time the plants are in the dark. I think this might cause stretch.

I put the seedlings at 12" under the HPS with a fan blowing across them. At 12" the back of my hand feels warmth but no heat, and with the fan, neither.

I don't know why more people don't use HPS for seedlings. We know it's where we want to get them as soon as possible, so why not all the time?

If you can get it closer with the fan why not? I think the stretch may be because of the 12/12 mine did the same but all plants during 12/12 do it so makes sense right? Start a grow journal bro I'll be sure to check it out

Earlyriser76 said:

Thanks everyone. I'm getting stretch on my cfl's which makes me think they are not the best. They claim to be 2700k but I'm not fully convinced.

I'm also trying to run 12/12 from seed so 1/2 the time the plants are in the dark. I think this might cause stretch.

I put the seedlings at 12" under the HPS with a fan blowing across them. At 12" the back of my hand feels warmth but no heat, and with the fan, neither.

I don't know why more people don't use HPS for seedlings. We know it's where we want to get them as soon as possible, so why not all the time?

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I have a 600 watt HPS and using it for seedlings would equate to using an elephant gun to hunt gophers.

Even at 50%, that's way more than the seedling needs, so kind of a waste of power and light bulb lifespan

I use CFL and/or LED bulbs for the first 2-3 weeks and I never had stretch issues, just keep the bulbs within 1 - 2 inches

ISK said:

I have a 600 watt HPS and using it for seedlings would equate to using an elephant gun to hunt gophers.

Even at 50%, that's way more than the seedling needs, so kind of a waste of power and light bulb lifespan

I use CFL and/or LED bulbs for the first 2-3 weeks and I never had stretch issues, just keep the bulbs within 1 - 2 inches

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Lol, I use 1000w hps on my seedlings. Their always tight and grow great provided the temps stay down.

I moved them all under hps yesterday and they look great today. Better than under CFL's for sure. I'm around 10-12 inches off the canopy and no burn at all.

I won't be using CFL's for seedlings anymore if I can avoid it.

Earlyriser76 said:

I moved them all under hps yesterday and they look great today. Better than under CFL's for sure. I'm around 10-12 inches off the canopy and no burn at all.

I won't be using CFL's for seedlings anymore if I can avoid it.

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Just keep an eye on them and the temps, as someone else pointed out you could cook them pretty quick.
youre only running 150w so it shouldn't get very hot at all.