Searched and get mixed answers. I have a bunch of plants. They were doing fine under 6 CFL bulbs. Today was really hot 90* with HIGH humiditiy. I went to check on them when I got in from work and now all the plants are curling DOWN and not looking good. I watered them yesterday. I did not overwater. nor use any fert. I use foxfarm soil. help! I just got a 150w HPS light too for my 1 foot plant to start flowering (not looking for a big yield as i'm learning still.
looks like overwatering to me... heat stress combined with overwatering can lead to that curling down in the pics. as small as those plants are, you shouldn't need to water very often at all, and you should let the tops of the pots dry up before you water. you can stick your finger in the soil, and when it's dry more than a half an inch down (for the black pots) water away! 90 degrees isn't ideal for cannabis, but it's not going to kill it either. I've ripped crops in the high nineties before with few problems. is this 90 degrees outside or inside the room?
I would crack open a aloe vera fillet into the watering jug, stir it in and add a pinch of citric acid to arrest the aloe from fermenting. Aloe contains salicylic acid that is linked to plant resistance to stress, including heat stress. Regarding over watering, I wouldn't worry about it, then again my soils are loaded with redworms and aerobic microbes.
Over watering is watering to frequently and under watering is not watering often enough. Both will show signs of drooping. Just stick your finger down about an inch or so and if it feels kind dry then water. Also when it does need watered you can pick the pot up and feel how light it is and learn by if the pot feels light and needs watered or not.
Overwatering droop and underwater droop look different. Overwatering causes a droop that curls under like your pics.... usually followed by deficiency symptoms, then root rot, and then death. Underwatering causes a droop where the leaf tends to hang straight down (wilt), especially in severe cases. This is also followed by signs of deficiency. Tplat's advice to feel the bucket weight is the best way to measure water content. If you're not sure what the weight should feel like... fill two buckets with soil. One bucket should be bone dry, and the other should be watered until you see water coming out the bottom. This will give you a good frame of reference (assuming you use the same buckets). Water when bucket weight is about midway between those two extremes. Hope this helps. =)
So IF it is overwatering which I don't think it is I should just let them be for a few days and hopefully they recover? I don't want all my plants to die :-/
If you overwatered you should be ok..just stop doing it if you are. I find the pick up method to be the best indicator of when you need to water. Pick it up if its heavy dont water, if it is water. Let it dry out some in between. It rarely if ever fails.
Stop watering, see if they pick up in 2-3 days.. if they get worse, they're probably underwatered.. either way, droopy leaves tend to be a water issue