Yellow leaves falling off at three weeks

The plants below are experiencing symptoms to what I have read in other threads: bottom leaves falling off, upper ones yellowing and or curling in. Both are about nine inches high and three to four weeks old (forgot the germination date). Lost two other plants completely last week.

I am thinking heat stress or too much water. This was part of my first batch, and did not have soil/light/ph testers on hand. I have 120 watt blue grow light bulbs over them, running at about eighteen hours per day, but the plants go outside when the weather is nice.

I have since tested, and nutrient levels are good. Depending on the tester I use, pH is between 5.5 and 7.2. I have raised the bulbs, which are now fifteen inches about each plant.

I now have two other seedlings growing in separate conditions: different soil, with each baby sitting under its own 120 watt Sylvania Spot Grow, on twenty-four hours per day. Want to avoid the same fate as the other plants.

Thanks in advance.

Are your lights cfl? If so than 15 inches isnt close enuff

Its hard to say what the problem is.. It kinda looks like heat is an issues and maybe over feeding possible, there also super stretchy probably from lack of light , are you using cfls and if so put the light like 1 inch from the top.
Also you dont have one yet get a fan blowing on it,,

I would also check the soil ph GROWFAQ and start LST GROWFAQ

No I am using a blue grow spotlight. See the attached picture, bulb on the left most side. If I place the Sylvania grow light closer to the plants, they will definitely wilt.

If I am understanding you, then I place a CFL (what wattage?) over each plant. When do I switch to the blue grow lights?

Oh shit, that's your problem right there. There are no incandescents other than metal halides that will offer sufficient light of the proper wavelengths. I'm growing outdoors, but I have grown lots of corals and other photosynthetic organisms and I can tell you that you'd do better even just using standard normal output fluorescents. I believe that the GrowFAQs have proper CFL ratings, and there are others who'll chime in and give up that info right quick. Also, try the search function, might help.

That makes sense. I am reading the GrowFAQ now. Have to hit the hardware store on the way home.


Thanks.

Im not positive but Ive seen in the hardware stores bulbs that say Plant light but if you read the back of the box its just for making your plant look heathy under the light nothing to do with making it grow better. Is it possible thats what kind of light you have.
I would get cool white and worm white mix for veg, If your gonna flower with CFLs worm white is better Cool white is good for veg Sunlight or all spectrum is good for Veg to..https://www.rollitup.org/general-marijuana-growing/723-things-know-about-lighting.html

I purchased some high end CFLs at the hardware store at lunch, and will set up tonight. Based upon the pictures I submitted, is it worth salvaging my existing low light plants, or focus bulbs and efforts on the new batch coming up?

That's up to you... I don't remember what strains you're growing, or what. I'm expecting a special package today. Ooooo.. I'm getting so excited! And I redid my motorcycle seat today, too. Put on some diamond-shaped studs on it, reshaped the foam (the stock seat sucks ass). Can't wait to try it out!


Anyway, the plant looks young enough to recover quite well.