Mysteriously sick seedlings

[danjac82]

Hi guys, I'm only 12 days into a closet grow and having issues. I have 18 seedlings going under 7 23 watt CFL 6500k. Plants have been kept as close to lights as possible without getting hot but temps may have consistently been up into the 80s. I'm using promix with no added nutrients and watering with tap water. I believe I've been waiting for soil to dry decently before rewatering. 3 of my seedlings are sick within the last few days with leaves seeming to dry and get almost crispy while still fairly green. Downward curling. Leaves begin to fade. On two of the sick ones is small brown spots/brown cracks on leaves and concentrated toward leaf edges and tips on one of them. Im stumped and any input would be awesome. Not sure what the problem is or how bad it will get. If this helps, Some of my seedlings stretched the first few days due to being on window sill. Growth has been decent enough though until I noticed this on three of them. Not sure the humidity/temp but I moved the lights up a bit today. Could this be a watering issue or problem with temp/humidity combo? Poorly rooted? Lights have been on 24 hours for 12 days and just decided to give them a night cycle now

 

[Darnova]

I've never used Pro-Mix. Went to their website and couldn't find a clear list of what their fertilizer additives are.
All I read was "Controlled release fertilizer". These words remind me of Miracle-Gro brand chemical ferts, which is bad. Exactly which kind of Pro-Mix are you using? Pro-Mix comes with Peat Moss, which is acidic. It also comes with limestone, presumably to help control the PH of the moss.

It looks like you're seeing a severe Calcium/Magnesium deficiency. I'd once suffered that from Miracle-Gro soil. Whereas nutrient burn tends to start at the tips of the leaves. Your brown spots are more edge & inner. I've used Cal-Mag with great success.

Assuming the PH of your tap water is balanced (you've checked, right?), You need to check the PH of the wet soil that your plants are in. Cheap test kits are available.

As for soil dryness, you don't need to try and replicate the outdoor weather. A consistent amount of moisture is better than trying to dry out the soil before watering.

 

[danjac82]

Thanks alot man. This promix consists of peat moss, perlite, dolomitic and calcitic limestone, wetting agent and Mycohhizae. It's recommended by a lot of people I guess. No nutrients added. I haven't checked water pH yet. I'll get some cal mag. Thinking of maybe using to water or spring.

 

[Darnova]

The more I look at the first pic, the more it looks like a PH problem.

It's the "Controlled release fertilizer" which I see as non-organic (harsh chemical). I wonder if you are having a problem similar to those who try to sprout in FoxFarm Ocean Forest, which is widely considered too "hot" for young plants.

 

[danjac82]

The more I look at the first pic, the more it looks like a PH problem.
The promix has no fertilizer in it and it worked before without an issue. Its recommendee by many growers. I am in a budget right now and thinking this may help a few possible issues. Tell me what u thing. Im gonna go get some cal mag to water into the cups and top the promix with some lime. I'll be repotting in a few days. I'll add more lime into the repot soil. Think they could use other nutrients yet or just try to get this current issue under control?
It's the "Controlled release fertilizer" which I see as non-organic (harsh chemical). I wonder if you are having a problem similar to those who try to sprout in FoxFarm Ocean Forest, which is widely considered too "hot" for young plants.

 

[danjac82]

Using promix which has no fertilizer. I'm thinking I'm gonna water adding cal mag and top soil with more lime even though the promix has like in it. It's supposed to be pH around 6.5 but havent actually checked. I'll be repotting in a few days amd will add lime into the repotting mix. Third set of leaves is coming out. Should I wait to use fertilizer?

 

[Alienwidow]

I've never used Pro-Mix. Went to their website and couldn't find a clear list of what their fertilizer additives are.
All I read was "Controlled release fertilizer". These words remind me of Miracle-Gro brand chemical ferts, which is bad. Exactly which kind of Pro-Mix are you using? Pro-Mix comes with Peat Moss, which is acidic. It also comes with limestone, presumably to help control the PH of the moss.

It looks like you're seeing a severe Calcium/Magnesium deficiency. I'd once suffered that from Miracle-Gro soil. Whereas nutrient burn tends to start at the tips of the leaves. Your brown spots are more edge & inner. I've used Cal-Mag with great success.

Assuming the PH of your tap water is balanced (you've checked, right?), You need to check the PH of the wet soil that your plants are in. Cheap test kits are available.

As for soil dryness, you don't need to try and replicate the outdoor weather. A consistent amount of moisture is better than trying to dry out the soil before watering.

Your analysis is all wrong. Pro mix has minuscule amounts of fertilizer in it. Its nothing like miracle grow at all. One is a potting soil with added slow release fertilizer beads, and the other is a soiless peat based medium with almost no fertilizer. The joy of using a soiless substrate is you control what goes into the plant and not team MG.
Also ive never seen a plant that young have calmag deficiancy. Calcium deficiancies are different than magnesium deficiancies as well. The two come in the same bottle because theyre two important micro nutrients that cannabis loves to suck up. Some of the micros the plant needs are found in the tap water most of us use especially the calcium. RO systems need a constant supply of calcium because its all filtered out and usually will result in calcium deficiency.
Without asking too many questions i would say its one of two things by having a quick glance. One is minor light burn and high temps. Many new growers jam the lights so close to seedlings that they show white spots which is dead plant matter from burning them. Id look into threads on that and see if that may be the case. Seedlings can have the light a little farther away than plants that are in full swing. Those plants look like theyre trying to escape the light to me.
If the lights havent been way too close, and the temps havent been way too hot at the plant level (IN THE CANOPY), then id say feed them a splash. Nothing major, just a few drops or a baby dose of food to get them moving. If its a deficiancy then its probably an NPK deficiancy and not a micro deficiancy at this stage. Good luck with the trial and error stage of becoming a grower. Its the hardest, but its worth going through

 

[Alienwidow]

Using promix which has no fertilizer. I'm thinking I'm gonna water adding cal mag and top soil with more lime even though the promix has like in it. It's supposed to be pH around 6.5 but havent actually checked. I'll be repotting in a few days amd will add lime into the repotting mix. Third set of leaves is coming out. Should I wait to use fertilizer?

Dont add soil, dont add calmag, dont add lime, and dont worry about PHing a seeding. Get your temps and light distance right, add a teeny dose of food, and see what happens. Id bet good things. If you start adding things you dont understand and chasing ph, youll mess everything up. Do mass reading.

 

[Darnova]

"Your analysis is all wrong."
My words right back at you.

Light burn from 23 watt CFLs? Not unless the plants are directly under the light and no fan is used. Also, it's the older bottom leaves showing dead areas, not the upper leaves. Light heat is not the problem.

I agree that it's probably not a Cal Mag deficiency, but that PH needs to be checked, as that can present exactly as is shown in the first pic. At the very least you want to eliminate PH as a cause. It's cheap & fast to test, so no reason no to.
To clarify, I'm not stating outright that you have a PH problem, only saying that were they my plants, PH is the first thing I'd check. If the PH is not right, then the plant can't process any nutrients properly.

Also, NPK deficiencies do not start with well-defined dead brown spots like those pictured.
Nitrogen, Phosphorus, Potassium deficiencies all display yellowing of leaves among the first signs of trouble.

But hey, don't take my word for it, check out this great thread...
https://www.rollitup.org/t/guide-to-nutrient-deficiency-or-toxicity.488004/

The leaves from the first pic are a healthy green aside from the well-defined dead spots. Absent any nutes from the bag, you'll want to start feeding them a very mild solution. Personally, I've used FoxFarm Grow Big with great results (diluted for young plants).

Here's a chart..

 

[Darnova]

Of the following real-world examples, which looks most like the current situation?

PH Problem

Nitrogen Deficiency

Phosphorus Deficiency

Potassium Deficiency

 

[Darnova]

Check out this thread here..
https://www.rollitup.org/t/help-needed-ph-problem-pics.258385/

While there may be other things going on with his particular situation, his own PH analysis shows he has an acidic PH problem. Peat Moss is naturally acidic with a PH of 4-5.
Look kinda similar to your situation?

Also, I have one little seedling, about the exact same age & size as yours. The topmost leaves are exactly 4.5" inches under a 250w CFL bulb, with a very gentle breeze blowing on it. Mine shows no form of bleaching, or heat-related stress. Perfectly healthy.

 

[tstick]

Could be heat stress and too much light -which sometimes LOOKS like nutrient deficiency... "7 23 watt CFLs..." will produce a lot of heat at close range and that heat will accumulate in a small space. Place your thermometer next to one of those bulbs and see how hot they get at close range!

I'd switch to LED light bulbs if you need to use bulbs. I used the 9.5 watt Cree Home Depot bulbs in 5000K for seedlings and I literally had the bulbs touching them without harm. They seemed to grow just fine. The bulbs produce less heat than CFLs....but the base of them does get hot so I had to be careful to keep leaves away from that part.

-my 2 cents

 

[danjac82]

Thanks guys. Good shit. I think it's a combination of what you've both mentioned. Thinking some heat/light stress along with a possible calcium deficiency. There should be no calcium deficiency because this soil has dolomite lime and pH is supposed to be close to 7 in this promix. That makes me think A. they skipped the lime in the bag or B. pH is off and plants aren't getting calcium. Maybe my tap water is throwing the pH off. I raised the lights, got a fan on them and looking to get some cal mag and some bottle water. Spring or reverse osmosis. I don't have pH tester kit and im nervous about the tap water. The leaves that are drying before yellowing are a big question still. I can only think light/heat. How about humidity?

 

[tstick]

Growing in confined spaces can be a real pain to dial in. Airflow and fresh air and heat and proximity of lights, type of lights, etc. can be challenging to get right...and then, as the plants get bigger and transpire more water into the environment, the microclimate is in need of constant adjustment.

Get one of these from Amazon....Every indoor grower should have one or something similar:

https://www.amazon.com/Humidity-Thermometer-Hygrometer-G4E435T1-34452-3T781130/dp/B01MAT2MXY/ref=sr_1_11?ie=UTF8&qid=1478635444&sr=8-11&keywords=gardening+thermometer+digital

 

[danjac82]

OK, big news. They've got worse since the last I checked them 5 hours ago. Brown at edges and leaf tips getting worse. Dryness getting worse. Some weird light green near veins. Lights have been up and fan on. No heat issue. What the hell. Here they are now

 

[polishpollack]

there's more than one promix. which one are you using, HP, BX, MP? Some potting soils are not well suited for seedlings. From some of the pics up, it looks like pH is an issue.

 

[danjac82]

It's promix HP. I got a bad feeling I'm gonna have to start over and I dont have much money to spend. If I did, I was thinking jiffy seed starter with added lime to be safe. Hmm. Wish I could pin down what the issue is here.

 

[Darnova]

You mentioned using tap water. Tap water, especially in urban ares, can be treated with chlorine, fluorine, and other chemicals. Depending on the concentration, that can be bad for plants. Usually allowing your tap water to sit for 24 hours in an open container will allow for most chlorine residuals to dissipate. Tap water can also contain salts for softening, which plants don't like.

I'm wondering if you have more than one problem hitting your plants at the same time. Perhaps lack of water combined with bad PH? Or too much wind from the fan is drying them out?

Based only on the information you have provided, I'd recommend picking up a couple of gallons of distilled water (very cheap) from a grocery store. Distilled water should have a neutral PH of 7. I would then flush the dirt very thoroughly. Then place them about 5-inches away from your CFL lights and allow for only a gentle breeze blowing on them. Make sure the grow space heat is no higher than 80 degrees Fahrenheit (for healing purposes).

Wait at least 12 hours to see if the damage stops or reverses.

 

[danjac82]

Thanks man. I've been reading and promix HP can have a low pH. I'm to pick up the distilled water and sprinkle some fine dolomite lime on top of soil. Wondering what the fastest way to raise pH cheaply is. Lime is cheap.

 

[danjac82]

Seedlings were doing good, looking good until day 10. That's when I noticed tiny rust cilores spots/cracks on a few of them with leaves drying and rough and ceiling under toward ends. Leaves still green when they get dry. Today ( day 12) condition are bad on three of 18 plants and in just the last 5 hours I've noticed symptoms showing on about half of the rest. A mix of symptoms, Brian edges and leaf tips on most with the leaf drying. Curling under on most leaves. Light green around edges and veins on a few. Claw leaves on the worse ones and a few have leaves turning up as they dry and edges get brown tipped. Watered twice in twelve days because mix stayed moist. I planted in more soil in those cups than I should have maybe, but they are still small cups. Waited til soil was dry on about too inch before watering. Leaves didn't get to the point of dropping before I watered. I don't quite water till I get drainage but it feels pretty heavy and moist when done watering. This is a quickly emerging thing that's picking up fast. Can't remember which ones I watered when but maybe they've gotten worse as I've watered them. Seems a pH issue. The soil with a low enough pH and the city water is a mystery. Thinking top soil with dolomite for next watering and then transplant into a soil with added dolomite. Water with distilled water. How about reverse osmosis or just try regular gallon bottles?