Help me. I'm a serial seedling killer

[case]

I had a whole thing written up, but it’s too long. Here’s the short version. 18 seeds later and I’m losing all of them 6 at a time over the last couple months. Any help would be

I think this one is pretty much lost. I Germinated using the paper towel method and it was a monster in the paper towel almost over night. This was planted on 2/5. Other than some spritz of water in the dome with a spray bottle I’ve watered twice: 30ml on 2/12 and again 30ml on 2/21. Before watering on 2/21 soil was super dry and things have gotten worse since. The leaves started curling down today (2/22). Here’s some specs:

Light 300 par
Temp 75-80
RH 40% (so dry here)
Soil FF Happy Frog
Water RO
Additional Nute: None

Here’s some pictures from today (2/22)

[Borderryan22]

Do you have holes in the bottoms of the cups?

[case]

There are four smaller holes then I cut off the bottom corners as well.

[Mmanson1981]

Need to up the humidity

[Tdh3712]

I find you dont even need to water sprouts. The mist bottle is enough.
I spray my soil like 4 times, and then the dome.
Thats it.

[Tdh3712]

Sorry I was on my way to work but I thought id come back and expand because I struggled with the seedling stage when I started out. I feel your pain.

This is my diagnosis: they are overwatered. 60ml of water over 2 weeks might not sound a lot but it is. The problem is: even though you have holes in the bottom of the cups its not enough water to drain out the bottom but it is enough to cut your roots off from oxygen. Almost all of the 60ml is still in your soil. Seedlings are unable to transpire. Hence the need for high humidity. It might be 40% in your grow room but under that misted dome it will 100% be in range. You’re looking at 60% under the dome, at least.

This is my solution.
You need to dry out the soil. Since you’re low room humidity I would put a dome back on but dont mist it. Wait a few hours for water in the soil to evaporate and cling onto the dome. Once moisture has built up. Take the dome off for a few minutes and give it some air. Repeat for a few days. You will not need to water that plant again until its got its first set of true leaves. Keep misting the dome, and mist the soil after this if you need too.

I hope some of this helps.

[case]

Thanks a lot for checking in on me. I’ll give it shot. I’m in a pretty dry area so outside the propagation tray dome it’s around 30%.

40ish is the average in the dome. I have a humidifier if it makes sense to run that.

[randylilgnome]

So the seedlings start to wilt or curl downwards after about 2 weeks, is that correct?

How long do they live for before they die?
How big are they when they die?
Anything else that you can think of that you do to them?

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You don’t need high humidity for them to grow. We have 30-40% humidity here during summer and the seedlings grow fine. You can increase it if you like and most people say 60% is ideal but it won’t be what’s causing the problem.

Lower humidity means you normally need to water more often but you have to test the soil to see if it needs moisture. I stick my finger in the top of the soil. Push it in about 1 inches for small containers (like your cups) and 2 inches for bigger pots, see if it’s damp. It it’s dry, then water it so the water drains out the bottom.

Don’t let them sit in water though because that causes root rot and the plants wilt and die even though the soil is damp.

You don’t need to use reverse osmosis (r/o) water for plants. Plants need nutrients and trace elements (including chlorine, copper, zinc) so tap water is normally fine unless it contains toxic chemicals, in which case r/o is better for you, your pets, and the plants.

If you do use r/o water, you will need to add calcium, magnesium and a full range of plant nutrients to the water so they don’t get deficiencies.

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I soak seeds overnight in warm tap water, then remove most of the water and let them sit in a thin layer of water. When they start to show a root, they get sown into potting mix or coconut coir.

As soon as they are sown, I give them a good drink with fertilizer water and then don’t water again until the soil starts to dry out (finger test). In hot or dry climates you can put some plastic lunch wrap or a sheet of glass on top of the containers to trap moisture and stop the seed from drying out, but remove it as soon as you see the seedling start to emerge.

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Don’t bother with a humidifier. You can increase the humidity around the plants by having the pots sitting above a tray of water or having cups/ containers of water next to the plants.
eg: get a plastic storage container and put a couple of inches of water in that. Then get a smaller plastic container and put the pot plants in that. Put the smaller container with the plants in, in the bigger container with the water. The pot plants will be separated from the water but the humidity around the plants will go up quite a lot.

[DEEPDIVERDAVE]

@case

40ish is the average in the dome.

Spray the inside of dome for raising dome humidity

[case]

Thanks. Let me go back to the beginning of this. Last part of Dec I dropped 6 seeds into paper towels thinking plenty of free time around Christmas. Free time didn’t work out but had these seeds germinated and needed to get into soil. Christmas Eve everything closed but ace hardware so went with a bag of organic seedling potting soil (forget the brand). Got them planted and they were doing well. - watering small amounts with bottled spring water.

2 or 3 weeks and I’m concerned about this ace hardware soil and feel like need to transplant so bought some gallon containers and FF Happy Frog from a local nursery.

little plants looked good - they were on second set of leaves. Good color. Pulled out of solo cups and roots looked good. I could have left in the cups longer but went ahead with transplant. After that no new growth and within a couple weeks all were sad yellow looking like the current one.

those 6 stalled out and figure quicker to start over. I dumped each one out and inspected them. Soil was moist but not wet. Squeeze test clumped but nothing dripped out.

the roots had been growing into the happy frog soil. Like a lot

Discarded all of this mess and started next round. I made some early mistakes with germination and two didn’t pop at all. 5 of the 6 seeds wasted. One made it - original picture I posted.

Planted in solo cup with second bag of Happy Frog and switched to RO water.

I have 6 solo cups going now with three different strains

1 planted 2/5 (1st post) basically gone at this point

4 planted 2/12 these ones had a lot of early stretch that stopped with additional light added on 2/16. They are now starting to yellow

Last one planted 2/15 - experimenting with less soil in the cup on this one. This one is still ok.

I’ll post some pictures of each.

[case]

Here’s some more photo’s – these were taken 2/22

Motherload Kush 1 (planted 2/12)

Motherlaod Kush 2 (planted 2/12)

Madberry 1 (planted 2/12)

Madberry 2 (planted 2/12) – this one had a helmet issue and is very slow growing

Lunar Cheese 3 (planted 2/16)

[case]

Thanks for the photo. Do you all find it more effective to dome the plants individually like this verses the propagation tray with dome type of setup?

[Tdh3712]

Have you watered the Lunar Cheese twice too? And are the vents open?

[sparker]

I put mine into water 2-3 days later they sprout, at about 1/8 -1/4 inch long i put into dirt in an italian ice cup with 5 holes drilled the bottom. give a good soak, let drain. a few days later when i see a sprout coming through the dirt then right into the tent with a clear plastic cup on top like a dome with light on low. condensation should form on the clear cup. In a few days after 4-6 leaves grow take the clear cup off and spray the top of the dirt only! the don’t need regular watering right now. This has been working for me since 2017 3 grows a year. Good Luck.

[DEEPDIVERDAVE]

DDDs Indoor Jan 2025 ILGM AFGHAN AUTO Seeds

Getting ready for Jan 1, 2025 Seedling starts. ILGM Afghan Auto seeds (three). Soil-FFHF/Mycorrhizae cup ONLY germination method. [ILGM-AFG-Auto Seed-soil drop 12-27-2024] [ILGM-AFG-Auto Seed-soil drop 12-27-20241] Pre-wet soil with distilled water-runoff measured PH 5.5/ 650 TDS [Three Cups FFHF&BigFoot]. Domes misted and placed over solo cups. [Three Dome 1] Heat source located. [Tent heater1] Fun weather for the next week [Weather 7 days1] No Snow (for us), Yeah So, rain for 6…

Soil only germination was an experiment.
My bag seed bank allows for learning or sharing.
Forum allows for sharing and learning with others.
Do not water your germinated seedlings.
If dome stays moist, soil is damp.
If dome dries, soil is dry or drying.
Seedling roots do better in dry soil seeking the moist adjacent soil.
Hence Dome and Dome watering

[case]

Thanks everyone. Sorry about the late reply. I didn’t realize there was a daily post/reply limit for new accounts.

Lunar 3 has only had spritz with squirt bottle around sides of cup. I gave a bit today weighed about 4 grams more after squirt bottle.

I leave vents open 50%.

[Tdh3712]

So, yeh.
Theres nothing wrong with the lunar at all. Its perfectly healthy.
Some of the others are showing signs of over watering. So follow the above steps.
If you close the vent in the prop the humidity will rise.
The reason there is slow growth is because at this stage the plants are building a root system. So all the growth is going on under the soil.
The plants you have with curling leaves are slightly over watered but you can fix that.
The others like the lunar. Nothing is wrong.

[Storm]

Welcome to the forum.

[randylilgnome]

I think they look alright. In the first pictures (first post) the cotyledons are starting to look yellow but the first set of true leaves look green. This is normal and plants will suck the nutrients out of the cotyledons within a few weeks of sprouting. The cotyledons are the first leaves you see on a plant when they sprout and are the rounded leaves. The first set of true leaves are the ones that have the pointed ends and serrated sides.

New leaves can look pale green or light yellow for the first few days but usually green up after that.

If plants turn yellow, it’s normally caused by a nitrogen deficiency or an iron deficiency (nitrogen deficiency being much more common than iron).

If plants stop growing it is either a lack of nutrients or not enough light, or a disease (usually root rot). The most common cause is lack of nutrients. Plants can also stop growing for a bit after being transplanted, especially if they go into a different type of soil or their roots get damaged. Baby plants (less than a month old) are more likely to go into transplant shock and stop growing for a bit. If the roots are growing into the new potting mix but the leaves aren’t, it can be lack of nitrogen, which is used for stem and leaf growth. Phosphorus is for root growth and potassium is for flowers and fruits.

If the problem is yellow leaves, then add some fertilizer with a high nitrogen level.

[DEEPDIVERDAVE]

@case

Do you all find it more effective to dome the plants individually like this verses the propagation tray with dome type of setup?

Both methods employed when desired.
Single dome advantage “watching the moisture on the dome” as a reflection of soil moisture. Seedling leaves touching dome (both sides) indicate large enough for life w/o dome.

Tray dome utilized occasionally or gallon jugs, too( vented,already)…