First time grower - Seedlings too small for their age

[pitufin]

Hello, this is my first time growing cannabis so any advice is appreciated.

• Cupboard: 60cm (2 feet)h / 40cm (1.3 foot)w / 30cm (1 foot)d
• Lights: 2 x 42w CFL + 2 x 20w CFL
• Seeds: Bagseeds (unknown different strains, probably indica type)

Soil: 50% perlite + 50% (non-branded) soil from a local nursery.
The bag reads something like this (translated from Spanish):
60% "black soil" / 20% manure / 10% perlite / 10% "vegetal organic matter" ¿?
Humidity: 19-24%
Organic matter: 8-13%
Carbon nitrogen ratio: 14,6%
Total nitrogen: 0,5%
Ph: 6.5-7
Ashes: 75%

Pots: 10cm diameter x 10cm height (4x4 inches)

Seedlings are no more than 5cm (2 inches wide)
Most of them are around 3/4 weeks old. To me, they look really small. The cupboard picture is a bit dark but it's because the light makes my cellphone camera act weird.



What do you recommend? Thanks in advance

 

[TheAntagonist]

Well here is my 2 cents as they say, the soil looks dry and a few look like they may have yellowing at the edges again could be because they are dry. what are the kelvins on those CFL bulbs 6500k? daylight or frosted? any idea on the ph of the water you are putting in?

I'm along for the ride any questions ask someone will answer.

 

[Robert Celt]

Welcome to pitufin

From what I can see in the first picture, some of them look quite yellow. And yes they are small for 3-4 weeks old. Are you planning to feed them with nutrients? If they are as yellow as they look, chances are there isn't enough nitrogen in the soil mix to allow them to thrive.

 

[pitufin]

Hi, thanks for your time.
CFL bulbs are:
20w:
6500k "daylight white"
1000 lumens

42w:
6500k "daylight white"
2650 lumens

I'm using tap water. Unfortunately, I don't have a ph meter, they are really expensive here. I believe our water ph should be around 7 (neutral) but I could be wrong.

2 out of the 6 seedlings look really yellow. Let me take a better picture so you can see them.

 

[pitufin]

Sorry for the repost, here's the picture:



I bought a set of fertilizers at a local grow shop.

One is for veg state, it's supposed to be a nitrogen mix. It looks like a bunch of ashes. Actually, it looks like those tiny scales you can find in fish food.
Composition:
"Organic nitrogen" 13.6
"Phosphorus" 0.11
"Potassium" 0.07
"Sulphur" 0.3
"Calcium" 1.66
"Iron" 0.04
"Ashes" 13.7
"Organic matter"80.6

The other two are bat guano and cormorant guano but I have never used them yet.

Two weeks ago I added the nitrogen fertilizer mixed with water and some of the seedlings started to depict brown tips (you can see them, specially in seedling #1 but that could have been caused by something else.

I am now afraid of adding nitrogen to the rest and burning them.
Thanks in advance,

 

[Robert Celt]

Mix your nutes at 1/4 strength and try that to see how things go mate

 

[TheAntagonist]

Sorry for the repost, here's the picture:



I bought a set of fertilizers at a local grow shop.

One is for veg state, it's supposed to be a nitrogen mix. It looks like a bunch of ashes. Actually, it looks like those tiny scales you can find in fish food.
Composition:
"Organic nitrogen" 13.6
"Phosphorus" 0.11
"Potassium" 0.07
"Sulphur" 0.3
"Calcium" 1.66
"Iron" 0.04
"Ashes" 13.7
"Organic matter"80.6

The other two are bat guano and cormorant guano but I have never used them yet.

Two weeks ago I added the nitrogen fertilizer mixed with water and some of the seedlings started to depict brown tips (you can see them, specially in seedling #1 but that could have been caused by something else.

I am now afraid of adding nitrogen to the rest and burning them.
Thanks in advance,

What nutes you using? try 1/4 dose them bring it up slowly

 

[pitufin]

The nut pot doesn't really have a brand. I tried my best at translating and describing the components in the previous post.
I have only used it once (1/2 strength), and it didn't do anything good I guess, since they are still pretty small.

Do you think the soil is bad? Maybe it's not meant for this kind of plant and I should try a different soil.

 

[TinkerFarms]

Just for my own info how can you fix this problem?

Welcome to pitufin

From what I can see in the first picture, some of them look quite yellow. And yes they are small for 3-4 weeks old. Are you planning to feed them with nutrients? If they are as yellow as they look, chances are there isn't enough nitrogen in the soil mix to allow them to thrive.

 

[zBRiCKz]

You need a lot more light too honestly.

 

[Robert Celt]

OK Tinker and Pitufin, lets go back to basics. Cannabis is an annual "weed" meaning it goes from seed to death in one year, usually about 8 months depending on where its grown.

All plants need 4 things to grow, light, CO2 (from the air), water and nutrients. Because it has such a short life span, it grows very fast and needs LOTS of the above. Outdoors it will get everything it needs provided its growing in good ground and not in too arid a place.

Inside, we have to provide what it needs. When your plants don't thrive, and its getting light, water and good airflow, that leaves soil as the part lacking and the girls aren't getting the nutrients they need.

So in pitufin's case, got light (enough for the size of the plants) but will want more later, they don't look like the leaves are dry from under watering, assuming there is enough air exchange, that leaves the soil lacking the nutrients needed for the girls to grow well. I say this because the size of his plants in those pots, they shouldn't be root bound. Although they could be water logged if there are no holes in the bottom of the pot to allow excess to run off.

If they aren't water logged then I would suggest seeing if you can source some worm castings, add about 1/4 cup (125ml) in a gallon of rain water (4 liters) and mix very well. Then water your girls with that once every few days for the next couple weeks.

This will give your girls all the nutrients they need and won't burn them like chemical fertilizers. If you must use chemical fertilizers, use 1/4 strength and feed once every 4-5 days until they perk up.