When To Start Feeding Seedlings?


My girl is 9 days old (since emerging from medium). I have it under. HLG 350r light and a humidity dome over the plant.

Question - At what point do start fertilizing my GG4?

FYI - I have added more coco to the bag


Is it coco and perlite ?
If so ,you should be feeding it now.


Yes. Coco + perlite.

I’ll start tomorrow with a very mild mix of Jacks 3,2,1.


Do you have EC pen and Ph pen?


Be sure to cut out that starter bag( the roots can get stuck) and If you have a decent smartphone get photone and get a dli reading of about 13-15 and you’ll be good to start feeding


Yes. I have both


(Please guide me if i went off track)

I did my first fertilizer this morning.
Currently my light is about 15” above the plant canopy. > Light is dialed down to 20% in order to get a DLI reading of about 15. (Hope I’m doing this right).

My input water is PH 6 and 410 EC. Seems so light?
Watered till runoff. Didn’t test runoff. Forgot and dumped it.

Since it’s Coco, should I fertilize/water more than once a day? Always at runoff?

Should I keep the dome on? When should it be removed?


  • Tent - 2x4 AC Infinity
  • Exhaust Fan - AC Infinity Cloudline Pro T6 plus controller
  • Exhaust Filter - None “yet”. To be purchased
  • Oscillating Fans - Two AC Infinity
  • Light - HLG 350R
  • Fertilizer - Jack 3,2,1 plus silica
  • Medium - Coco + Perlite (Mother Earth)

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For enlightenment on feeding in Coco, I would suggest you read up on tutorials at Coco for cannabis .https://www.cocoforcannabis.com/toc/#fertilizers-water


With coco and Jack’s, begin feeding when you start watering. The first few days will be fine with a humidity dome, but when you start actually watering, it’s time to start feeding as well. With Jacks, you feed every time you water. At first, it will only be a few ml’s, but over the days you will have to increase to cups, then gallons lol. Jack’s is gentle enough that you can start with the standard mix.


Thanks. Actually, I have been reading a lot on that site. Ton of info and easy to get overwhelmed. I keep reading and re-reading.


I keep reading and re- reading too. :laughing:
It will sink into my brain ,eventually… :exploding_head:


You dont really need to start watering till run off until about week 3( there’s just not enough salt buildup to warrant it )but definitely give it at least 1/4 gallon a day to keep the roots exploring and every 3ish days id up the light about 3 more dli( seems like a lot but she ll love it) and no need for the dome and ppm of jacks seems low but since your feeding everyday its all being used daily rather then other nutrients that try to store in the medium

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I used to use glass bottles for my cloches .
Had too much moisture retention ie. rotting seeds.
So I now use cheap plastic sandwich bags which I place over the pot , mark the baggie where it touches the surface the pot sits on . Then poke I a couple of holes in the top to allow excess moisture to escape .

I start my seeds in 100% peat moss .
Pre- wet
Fill 2 1/14” pots half way .
Wash my hands A with soap and water for at least 30 seconds . Having grown vegetables and flowers for 55 years I am convinced many germination problems are caused by oils on my hands basically sealing the seed thus depriving the necessary moisture for germination from reaching the seed .And of course we know our hands are teeming with creepy biological creatures . Additionally I never touch the seeds . I pour them into my favorite shallow itty bitty pottery bowl. I then use a bamboo skewer to push the seed into the pot . Mist well . Cloche. Place in a kitchen cabinet directly ABOVE my LED under cabinet light , this seems to be the perfect temperature for speedy germination .Usually germination occurs in 36-48 hours .As soon as the seed shows any sign of germination I fill the top half of the pot with pre moistened peat moss . Put the cloche back on and put the pot back into the kitchen cabinet . Mist daily . As soon as I see the seedling begin to emerge I put it under a light . Seedlings require very little light , they burn very easily and remember a quick non stressed start equals a strong healthy plant .Typically the seedling stage lasts three weeks or until 4 real leaves show . About this time roots will be beginning to show under the pot , time to transplant to a 3” pot . From my gardening experience a seed which germinates poorly should be discarded. A seed has only enough energy to sprout and produce the first two leaves .

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Remove the humidity dome. I’m not a coco grower, but as far as the light goes, that’s what I use. I would have the light at least 24”, and on the first notch at this point. Here’s mine at day 9 as a comparison for you. I have found that this light is so good, to much light and the plant doesn’t want to put on height.


Thanks for the reply. Mine just seems to be stunted at the moment. I know not good for an auto to loose time.

I may drop another seed and see if I can do better.

A seed that just pops needs very little, the first two fat green leaves provides all the nutes a newborn needs to start with. They are the cotelydons (sp) leafs.

Mil litres water to start with. Do not water on the jiffy pellets. Water the edge of the jiffy pellet circular moving slightly away from seedling to promote root growth outwards.

The choosen medium may have nutes in soil like some fox farm soil do. Study your medium to know.

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Thanks for the reply and input.

The medium I use is coco + perlite (other than they jiffy pod, which I won’t use again)


Study her to start learning what she needs and when. The medium only needs enough moisture to keep her home nice and cosy for now, which is different to when you’re watering to feed her roots, which will be soon. But right now she’s just barely growing them. Remember the growth above the pot is often an indicator of root growth too. She looks like she’s getting too much light to me. But looking fierce :star_struck:

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We use jacks nutes all the way, a very diluted feeding when in coco is what we did for seedlings. Once or twice. As mentioned, study each plant. Currently, same age, my cake is drinking twice as much as runtz during flower.

I do not have an enclosed grow, my watering in winter was not even close to the watering regime late summer/fall.

We used the lift method, wet, to very dry, then watered and lifted each. A gallon of water is approx. 8lbs., thus half gal. 4lbs, you will know dry from watered by lifting.

Watering should be done at lights on.

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