Too Much Light?

[monty python]

I'm growing 2 plants. Under fluoresecents they do fine, but when I put them under an HPS (high pressure sodium) light they seem to wilt and not grow well.

The light is 2 feet above the plants.

What is the problem?

[Tonee4130]

how strong is the HPS?

if you only have 2 plants i am guessing you have a small grow area - the HPS might be too strong?

[rnf232s]

The biggest problem you will have with too much light is wasted electricity. Are your lights too close to your plants and having too much heat now. The HPS will produce a lot more heat than the flourescents so that could be a problem.

[slowmotion]

try to get a small fan running while using the HPS, might help with the heat. and also get one of those squirt bottles and mist the plant a couple times a day.

[GRB.4.Life]

Its not the lights thats the problem. Its the heat the lights produce thats the problem. In my opinion i would use the fluoros. But the HPS will give better results undoubtedly. Problem is, if you have poor ventilation you cant use the HPS due to the fact that it will heat your plants to the point where it evaporates all the chloraphyl and water inside the plants...

PS- I wouldnt suggest using squirt bottles to mist your plants. With fluoros this is OK, but still can cause problems. But with HPS and only having two plants, well, misting them will leave water droplets on them, the water droplets will become magnifying glasses and could possibly help kill your plants quicker...

[monty python]

In the last day, I put a small fan on them. Checked them just now. One plant is OK. On the other the top 3 fan leaves have curled up and died.

I turned off the HPS and am going back to the fluorescent. Maybe when they are bigger I can try HPS again - they are about 1 foot high now.

Previously I grew 5 or 6 plants in this same space using HPS and had no problem. These plants are a different strain (Oasis).

[llamaman666]

Your HPS might be too FAR away, I keep mine only 14 inches away, it is a 400 watt one though, how many watts does yours halve? if its a 250 then it would defnitly need to be a little closer.

[Tech]

Don,t mist it can scorch your plants.
If the light is 2 feet away from your plants then it,s not too close and it,s not too far away either.

I have had plants thriving in temps over 100 oF , i would check again if your problem is not elsewhere. :