Need help with seedlings? I got you fam.

SPLFreak808

Well-Known Member
A not so complicated guide to help those who have problems starting seeds or keeping them alive.

I'm not going to help you push your seedlings into peak growth limits, I'll save that for another time & i also will not teach you how to make your own soil, you can pm me for that, otherwise I'll keep it simple and successful with bagged soil.

1. Get everything prepped.
2. Germination.
3. Don't kill it with love.

Step 1, Prep your environment
.

Light - They don't need much at this stage, you can use about 5-10w of led (10-20w fluorescent) per seedling for the first week or so, keep low powered lights anywhere within 3-8" away, might want to start on the far "ish" side, stretching? Put it a little closer.

If you end up buying bulbs, start with 6500k so your seedlings don't stretch on you, or if you got a small hid (hps/mh/cmh) that will also work, again the blue spectrum is preferred and obviously don't put it too close and always keep temps in check.

HPS or MH/CMH with a glass, will have a good amount of IR, you'll want to counter this by keeping ambient temps at 75f +/- , the IR will naturally raise your foliage temp into the 80's.

About 2 weeks in, you should be able to throw it under a real light, 15-25w per square foot with high end leds, 25-40w per square ft with less efficient lights, again if they stretch or burn, adjust accordingly.

You might find that certain LEDs have too much intensity for seedlings, if this happens simply lessen the intensity by dimming or raising the light.

Lights should be at 18 hours on or more, 18/6 is the most common, do get an electrical timer.

Soil - I prefer soil without those extended time release nutes, To make it easy I'll just recommend a bag that I know will work.

Epsoma organic potting mix with 20% chunky perlite is easy to find, use a solo cup or any small container of similar size, make sure it's not clear/white & generously poke some small drainage holes on the bottom, fill it up with soil, water it in slowly until it lightly trickles out the drainage holes.

Temp/RH/airflow - germination and sprouts pretty much have the same temperature requirements, 75f-85f/55-65% rh is usually my sweet spot, a little lower with HID, personally i wouldn't go beyond 80f until you gain more experience.

An oscillating fan swaying across your seedlings is always good to have, once sprouted a light continuous passing breeze will strengthen those stems,bring up fresh air & will help dry out your soil.

If you don't have control over your temps, a horticulture style heat mat will work for germination and sprouts, simply going from 65f to 80f will noticeably speed root development and growth.

Step 2, plant your seeds.

Grab your seeds & planting containers, if your doing this at another time then make sure the soil is still moist before planting, put those containers under your light and have your environment set and ready.

Push the seed in no less than 1/4" no more than 1/3", cover the remaining hole so that its not exposed to light, from here it will usually take 1-7 days depending on seed health/viability, if your soil dries up before germination then just mist the surface with a sprayer otherwise leave it alone, don't pack the seed in and never pour a stream directly above it.

Step 3. Caring for fresh sprouts

Watering
- this is important here, you don't ever want to pool cannabis roots with water.

If you get an identical container and fill it with dry soil you'll have some reference to compare dry vs moist, you can mist the container with a sprayer if the surface dries out on you due to light ect but with tiny seedlings, don't pour in any water until it gets near the weight of your reference pot, when you do finally water, slow & lightly.

Keep in mind your light will assist with drying out the surface of your container, this depends on intensity, humidity & ambient temps, due to this you should NEVER time your waterings, you only water when they need it.

Water quality - with tap water, i don't go beyond 150ppm with young seedlings, most american cities should let you look up a water quality report, if its too hard you can dilute it with R/O to bring it down, if i use water only with good soil, I don't worry about pH, the lime & sulfur will buffer it along with the microbes, seriously its never been a problem for me even when they only receive rain water.

Nutrients - you should be able to make it 10 +/- days easy, cotyledons will support growth during that time and usually once nutes start running low you already have a well rooted container, by this time a transplant into fresh soil would be wise until you get to your final pot.

That's it! Hope this helps

Once you have everything in check, you can observe new growth every day, after transplanting they will explode with growth. Good luck!

4 days in - 20191212_192418.jpg

7 days in -
20191215_191608.jpg
 

xtsho

Well-Known Member
Good write up and basically the same way I do it. I like the fact that you don't have people germinating in paper towels but instead guide the grower to sowing seed directly in growing medium which is the way it should be done. If the seed will germinate in a damp paper towel it will germinate in damp soil. Skipping the paper tower step removes an unnecessary step and an additional opportunity for something to go wrong or for the seedling to be damaged. I don't understand the reasoning behind the paper towel method. Seeds from some plants do need to be germinated before planting. Cannabis isn't one of them since the seeds of cannabis sprout so easily.

Did I say I don't like the paper towel method but the planting straight to soil method in your instructions?
 

Hempire828

Well-Known Member
I got some seeds I can’t get these to crack for me...any help would be appreciated.. I’ve soaked them, paper toweled them.... nothing...I put them back in water...they are Sativa’s... I read somewhere it could take up to 3 weeks to germinate.. I’m sure these have drown... I don’t get it.. at first I thought I should’ve scuffed them.. but all six sunk to the bottom...
 

SPLFreak808

Well-Known Member
Good write up and basically the same way I do it. I like the fact that you don't have people germinating in paper towels but instead guide the grower to sowing seed directly in growing medium which is the way it should be done. If the seed will germinate in a damp paper towel it will germinate in damp soil. Skipping the paper tower step removes an unnecessary step and an additional opportunity for something to go wrong or for the seedling to be damaged. I don't understand the reasoning behind the paper towel method. Seeds from some plants do need to be germinated before planting. Cannabis isn't one of them since the seeds of cannabis sprout so easily.

Did I say I don't like the paper towel method but the planting straight to soil method in your instructions?
I'm against pre-germination, at least with cannabis, i mean people are free to do what they like but I'm trying to keep this guide on the fail-safe side & root shock is easy to do for the inexperienced, soil will hold moisture & heat better than a paper towel.
 

SPLFreak808

Well-Known Member
I got some seeds I can’t get these to crack for me...any help would be appreciated.. I’ve soaked them, paper toweled them.... nothing...I put them back in water...they are Sativa’s... I read somewhere it could take up to 3 weeks to germinate.. I’m sure these have drown... I don’t get it.. at first I thought I should’ve scuffed them.. but all six sunk to the bottom...
honestly bro, if you simply plant it in soil and keep temps/moisture in check viable seeds will germinate, If they don't, something is likely up with those seeds.
 

kmog33

Well-Known Member
honestly bro, if you simply plant it in soil and keep temps/moisture in check viable seeds will germinate, If they don't, something is likely up with those seeds.
I agree with this. I still use paper towel method because I don’t like potting soil for seeds that don’t pop.
 

olegren

Well-Known Member
Thanks for this guide! I'm planning to follow this method for my first round of seedlings, and I'm curious: My LED will only dim down to around 120W which averages out to 15W/sq. ft.

I have a question: Any risks associated with using too much light when germinating in soil like this? I have about 4.5' to work with in my tent (6' total) so can raise it quite a bit if that helps.
 

Igrow420365

Member
Great job on your seedlings. They look great!!! I’m a first time grower and love learning about other growers journey. I have a seedling time lapse which I believe turned out great.
 

SPLFreak808

Well-Known Member
Thanks for this guide! I'm planning to follow this method for my first round of seedlings, and I'm curious: My LED will only dim down to around 120W which averages out to 15W/sq. ft.

I have a question: Any risks associated with using too much light when germinating in soil like this? I have about 4.5' to work with in my tent (6' total) so can raise it quite a bit if that helps.
Should be fine if dimmed to 15w/ft2, i start seeds under the same type of power 25-30" away and adjust when needed, if your temps are low, the extra heat will help germination and growth.
 
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