Seedlings keep dying

[CannadaJ]

Hello and thank you for reading.

I'm a new grower, but have had 3 very successful grows so far (autoflowers from Crop King seeds). I managed 1/2lb in a 2X2 for 3 grows in a row.

All of a sudden, I've had 3 starts completely die off. I use the paper towel method, plant when tap root is 1/2" and they usually break ground a few days later. They grow to about one inch, and then nothing happens. I let the last round go for three weeks with no growth. When I dig up the stunted growth, the tap root is barely 2 inches and seems to 'thin out'. I don't over water. In fact I barely water.

I've been re-amending soil with worm castings and gaia green. Suspecting an issue with my soil, I planted the last grow in ProMix seedling soil with added perlite. Same problem. It broke the soil, grew to about an inch, and stopped. Roots not developing.

Temp: 75-77
Humidity: 55% (I know it's not ideal, but it's been 30% this winter and that's all my humidifier can achieve).
Water PH: 6.4 - 6.7

What could be causing my seedlings to die off? Do I have a bug, fungi or parasite in my soil that I can't see? It's very strange that I had 3 successful grows following the exact same methods.

Julien

 

[Cannaficionado]

My guess is the humidity is really too low.

Pro mix is also a peat based soil so soak it thoroughly before hand and let it sit 6 to 12 hours so the whole medium is hydrated evenly and not over saturated then pop your germinated seeds in.

Also maybe make a humidity dome out of the bottom of a milk jug. That'll help keep the humidity around the seedling, just poke a few holes in it for air exchange.

 

[Mañ'O'Green]

@CannadaJ Welcome to AFN Based on the description of the narrowing of the tap root I would guess a secondary infection from damage to the lateral root hairs. Maybe the brand of towels you are using lately has left over chemicals in them?

I know that a lot of growers swear by it and their proof is the fact that many plants survive the technique but unless seeds are old or have been stored poorly soaking seeds is not needed and can drown them. Then because they need the instant gratification of seeing the tap root they germinate them in paper towels. If you look at a tap root under 200x magnification you will see the “root hairs” that grow laterally out from the tap root. These become the plant’s uptake roots. They will grow into the fibers of the paper towels and are ripped off every time the seedling is moved or the towel is opened – ouch. This opens the seed to secondary infections. When transplanting, it is very easy to bump the tap root tip and damage it or kill the seedling – Why? White paper towels may have bleach and other detrimental chemicals remaining from the manufacturing process.

Put the fresh or properly stored seed ½” deep in a Rapid Rooter, Root Riot, rock wool cube or similar or right in the soil. Jiffy peat pots PH is too low – buffer them before use. Keep moist – not wet, and ~80°F, 60% humidity with your blue (veg) lights on and they will germinate if viable. I use 25% strength week one nutrients with a little kelp to moisten my starter cubes. Most strains will germinate in 5 to 7 days.

Have a reasonable expectation that 80% germination is a normal rate for cannabis seeds. I always drop a few extra to be sure I have 6 plants to grow in my legal California grows.

 

[NORBY]

As Mog says thiers a 80% chance of success normally
The method i use is....
Drop seeds in glass of water for 24-36 hours
Push any floating seeds back down if floating at the top after 6 hours.
Wait until seed shows a bit of tail and Sow your seeds...
Tail down... 5 ml below soil...
Then loosely cover with soil
Put a see through plastic cup over the seed area as a humidity dome for 3 or 4 days
Tissue can be annoying at times to use

 

[MrAutoGrower]

@CannadaJ Welcome to AFN Based on the description of the narrowing of the tap root I would guess a secondary infection from damage to the lateral root hairs. Maybe the brand of towels you are using lately has left over chemicals in them?

I know that a lot of growers swear by it and their proof is the fact that many plants survive the technique but unless seeds are old or have been stored poorly soaking seeds is not needed and can drown them. Then because they need the instant gratification of seeing the tap root they germinate them in paper towels. If you look at a tap root under 200x magnification you will see the “root hairs” that grow laterally out from the tap root. These become the plant’s uptake roots. They will grow into the fibers of the paper towels and are ripped off every time the seedling is moved or the towel is opened – ouch. This opens the seed to secondary infections. When transplanting, it is very easy to bump the tap root tip and damage it or kill the seedling – Why? White paper towels may have bleach and other detrimental chemicals remaining from the manufacturing process.

Put the fresh or properly stored seed ½” deep in a Rapid Rooter, Root Riot, rock wool cube or similar or right in the soil. Jiffy peat pots PH is too low – buffer them before use. Keep moist – not wet, and ~80°F, 60% humidity with your blue (veg) lights on and they will germinate if viable. I use 25% strength week one nutrients with a little kelp to moisten my starter cubes. Most strains will germinate in 5 to 7 days.

Have a reasonable expectation that 80% germination is a normal rate for cannabis seeds. I always drop a few extra to be sure I have 6 plants to grow in my legal California grows.

Solid advice. Just keep it simple. Water your medium, make a hole, place seed in, cover the seed a little and it should pop. No messing with towels and so on

 

[automan2]

Sorry to hear of your misfortune. For 20 years, I've simply 'planted' seeds in my chosen medium, bio bizz light mix and smoked a couple joints. 100% germ. No soaking, paper towels or fertility chants. Try it the most simple way.

 

[CannadaJ]

Thanks for the tips everyone! I just planted two Pineapple Express seeds (photos) in solo cups using Promix seedling soil and a bit extra perlite. Just soaked the seeds for 24 hours and put them directly into the soil maybe 1/4" deep with humidity domes on top. My autos all died again from the last paper towel method. I know that 55% humidity is somewhat low, but didn't think it could kill seedlings?

 

[MrAutoGrower]

Thanks for the tips everyone! I just planted two Pineapple Express seeds (photos) in solo cups using Promix seedling soil and a bit extra perlite. Just soaked the seeds for 24 hours and put them directly into the soil maybe 1/4" deep with humidity domes on top. My autos all died again from the last paper towel method. I know that 55% humidity is somewhat low, but didn't think it could kill seedlings?

I’ve never had any seedling die, despite humidity being as low as 50 in the past. I don’t think it’s been your humidity that’s caused it. Chances are it relates to your medium or the towels used

 

[Bill.de.Cat]

Every time I tried paper towel they died....chemicals or root tearing I don't know, but I don't try no more and I do quite well.

 

[CannadaJ]

I've eliminated the medium as the cause since I bought a new bag of seedling mix and still died. It must have been the paper towel. Just strange that they germinated, and a seedling broke the soil with a set of new leaves on all of them. Then they die. I don't over water, I barely keep it moist.