I have a few plants about a month old that have been under cfls and full spectrum led lights. The plants first round non-true leaves on a few have begin to turn yellow. I even saw a little yellow on the tip of one true leaf. (see pictures) The rest of the plant looks healthy but I was just wondering is this nute burn? Over/under watering? I water twice a week and have only fed once with 1/2 strength fox farm but they are in organic soil. I'm very new to growing and would just like some more experienced people opinion. Thanks Erik
what is the soil? what did u add to it? how do you judge their need for watering twice a week? is that wood mulch on top of the soil.?
Looks like possible potassium deficiency but I wouldn't get too concerned with the first few round leaves falling off. They don't look burned to me. Wood mulch isn't good in the soil because it consumes nitrogen as it breaks down. Some people like to top with sand it helps frustrate some bug activity and is pretty much inert as well as having good drainage. I like to feed my plants daily no matter how small or large they are. I tailor the amount and strength for small plants. They get as much as they want to feed. If that's just a splash then that's what they get for the day. This keeps the roots breathing plenty of oxygen all the time and keeps growth rapid in the early stages. Young plants are prone to getting water logged in the roots when the mix isn't done with lots of perlite or other drainage promoting material. Many experienced cannabis growers will mix about 20-30% perlite with whatever medium they use because they know that that will promote plenty of air to the roots for rapid growth. If that waters down the medium all you have to do is feed a little stronger to make up for the difference. I prefer precision perlite course. That's my go to brand. It's highly available at most good hydroponic supply stores in large bags for $20 range that last a long time and many plants.
Thank you so much. I had no idea about the wood mulch. It came premixed in my soul. So are these guys kinda done for ? I mean, they look healthy other than that. Or should I try to replant in new soil? I lost a couple to replanting stretched seedlings before so I'm kinda hesitant to replant just yet.
They look fine to me. Keep them riding and transplant them to a superior mixture. If you want a soil then fox farms isn't the worst option with about 25% perlite.
The soil may be my issue I suppose. The soil is an organic mix with guano earthworm casings and yes wood mulch. I can't remember the name of it. But I added nothing. I realize now that wood mulch is bad and plan on using different soil when I need to transplant them. As far as watering I do the knuckle test but it averages twice a week that it's dry past my knuckle. (Then I water) Is that okay? I'm very new so just asking...
lift the pots and judge the weight, when they feel empty (just before the plants start to droop) saturate them with plenty of run off. let them go until light again, then saturate the pots again.!! a $16 moisture meter might help, find one with long probes, the top 1/3-1/2 of the soil can dry out and the bottom 1/2 or 2/3 be wet, this causes 'wet feet', cannabis hates 'wet feet'.!! use the meter and lift the pots, eventually you won't need the meter.! for indoor growing from start to finish I would suggest inert potting mix and hydro ferts. used properly there is no difference in nutes and organics, unless you are eating the plants raw.! lol