Northern lights seedling leave curl


Strain; Northern Lights auto

Soil in pots, Happy Frog mixed with Ocean Forest

System type? Soil in cloth 5 gallon pots

PH of runoff or solution in reservoir? Haven’t tested yet

What is strength of nutrient mix? No nutes yet


Light system, size: 400 HPS, 18” from plants

Temps; Day, Night day 72 in room, 80 under lights. Night time 68

Humidity; Day, Night: 40% day

Ventilation system; Yes, two 60 watt fans blowing air out

AC, Humidifier, De-humidifier: humidifier

Co2; No

Hey everyone. First time post. I hope I did this right. I have 5 seedlings, one week old. 4 look great, but I have one Northern Lights auto that looks odd. It’s leaves are curling up. The light is 20” above. I watered day one, day 4 and day 8 only around the plants. Thoughts?


The fact that you haven’t yet tested the Ph is a big clue. The wrong Ph causes most problems, so I would do that first. Second, make sure you’re not over watering. Tiny seedlings need very little water because they are still growing roots.


What kind of light that one may just be more sensitive, mabey sit to side not directly under light also what are your temp


Thanks Raustin. I don’t think I was very clear with my support ticket. I ph’d the water I give them to 6.5. I haven’t been able to test runoff ph because I’m not giving them enough water to create runoff yet.ill side the plant more to the side to reduce the light a bit.


It looks stretched to me. If you move it to the side Id keep an eye one it


That’s the part I’m struggling with. They all seem a little stretched, but what do you do when you think they’re getting too much light, but they’re stretching? This is the first time I e grown in soil. The last two times I did hydroponics but it was such a pain, I wanted to try something that required a little less time. I would’ve had these in my aereogarden (yes, the small herb hydro unit as seen in tv :slight_smile: ) for a few weeks. It uses LED lights. Should I have kept these guys under LEDs for the first week maybe instead of going straight to HPS?


@HobbyGuy I’m not a indoor grower… But id say the most import thing is to get your ph right. If your Ph isn’t right nothing will be right. Just like hydro.
Got a feeling that will solve some of your problems. Then I bet you could move the light closer long as its not to hot. Just a guess from a sunshine farmer
Good luck with your grow!


I would like to see the humidity higher. The seedlings can also be sensitive to heat, which is what I think of when I see taco leaves.


Thanks for the feedback everyone.
The balance of all of these elements is what gets me. They need more light, but not more heat. The need humidity but not more watering. It’s amazing that plants brow at all! Lol. Trying to recreate nature give me a whole new level of respect for nature :slight_smile:
My plan is to add some more soil to get rid of the stretching (an inch or so), lower the light to 18” and kick on the AC at 72 degrees. I have a humidifier (Walmart special) going and it’s using about a gallon of water a day, but it doesn’t seem to be raising the humidity all that much. Is it too late to put these ladies under a dome?


No, but make sure nothing inside touches the dome.


I have one more question. I’ve read on here that many people use a spray bottle to water for the first few weeks. I also read that you should water in a small circle (not much wider than the width of the leaves), but so it slowly so it encourages the roots to grow down. I have notice that if I spray the top of the soil when the lights come on, it raises the humidity to around 55%. I’m only spraying enough to get the top 1/2 or so wet and it’s completely dry by night time. Am I doing any harm to my plants by spraying like this, and then doing a deeper water every three days or so?


How far away is your light because it really looks like it’s stretching to the light


@HobbyGuy if you do have a LED that is a little lower in power maybe it would be worth a go I’m sure you will get all the help you need here mate :v:


It’s a 400 HPS set at 18”. I had it a little higher, around 24”, until today. I was trying to keep the heat down. I’m have a small AC unit that I turned on today and set the temp to 72. It’ll probably still be 78 under the light, though.


@HobbyGuy the thing about rising your lights is that you’re plants will reach for the lights and stretch mate even if you had a 150 watt HID or even a 250 watt and definitely try get a Ph reading also :v:


So the rule is keep the light as close as possible without burning them, and then find a way to vent the heat?


Yeah your good where you at then


Hey everyone. It’s been awhile since I’ve posted about my grow. Mainly because it’s been a healthy grow for the last 6 weeks. Today, however, I noticed some of the leaves on my northern lights had spots and the leaf steams are turning purple. If I had to guess I’d say it’s a cal/mag deficiency but I’m not sure. I’ve beem keeping the nutrients at 1/4 strength and every other watering is with ph water only. The other three plants look great. I’ve just entered the flowering Star this week (these are autos) so I want to try and correct this before the others show similar signs. Any thoughts?


Yeah, that looks like calcium deficiency, and maybe some other deficiencies as well. I would up the nutes to at least half strength and add some Cal Mag.


Thanks for the quick reply. Since I’m growing 4 plants and giving them all the same strength, should I up them for all four or wait to see if the others show signs of deficiency first? I’m included to bump it up across the board and then watch for nutrient burn.