Seedling Leaves Drooping: Please help first time grower

[DjEclipse]

Hello all,

I apologize if this is in the wrong forum. I was not sure where to post this question.

I am a first time grower and terrible at that. I typically struggle to keep any plant alive in the house but determined to get this first attempt at Cannabis grow to produce something and learn form there.

I am growing in Pro-Mix Organic Vegetable & Herb Mix. They are feminized Indica seeds that germinated in a few days and seemed to sprout out of the soil in one day. After that growth has been slow and the first set of leaves are wilting.

Growing in a 3 x 3 tent with LED light 337W - 364W draw (450W) light. Tent is in the basement where it is cool and dry so an electric oil heater is used to raise temp's to 72-74deg. Humidity is low even with a humidifier running all the time, it struggles to keep it above 35%.

I have a 6" fan dialed all the way down to try and keep the humidity in the tent.

It is tough for me to determine if I have over watered or underwater as it seems I need to water almost every day as the soil looks dry, soil moisture meter is showing dry and sometimes the soil is separating from the sides of the container. I will water but no change in the plant's appearance.

Please see attached pic.


Is this over watering, or under watering?

Thank you,

 

[Bush Doctor 77]

Welcome. Water by weight. As soils ar shipped with minimum water, that's what you are shooting for before you water again. Get an identical pot, fill it with soil from the bag, and put both in a plastic bag to compare with your planted pot.

 

[DjEclipse]

Thank you for the quick reply.

I have a small scale I can start weighting before and after I water.

Do you think I am over watering?

I have an extra pot and can add soil to that pot, but I am confused as to what I am doing with the plastic bag? What do you meant by put both in the plastic bag. The seedling goes in the plastic bag as well? How will it get light?

 

[Bush Doctor 77]

Put it in a bag so it doesn't dry out over time if you keep using it for a weight reference. If you water when it looks dry, you are watering too often because the bottom will still have water.

 

[DjEclipse]

Ok I see what you are saying. I will just weigh the newly potted soil and container, write it down and use that for reference.

So the weight of the freshly potted, un watered soil is the weight I want it to be when I water again. Don't water before that. I will do this today.

 

[DjEclipse]

I started writing down weight's and how much water I gave them instead of just guessing at both. I guess lesson one is to start a journal.

I am wondering if it is under watering that is causing this?

I filled up one pot with fresh soil out of the bag and it weighted 183 grams and had a 4 on the moisture meter.

The fresh soil in the bag seems pretty moist and read a 7 on the moisture meter.

I took a side by side pic with the pot I filled up with soil out of the bag and the pot that has the seedling in (see the pic ). I think the seedling pot is really dry.



Seedling pots:
Pot 1 weighted 142 grams (2 on the moisture meter)
Pot 2 weighted 159 grams (2 on the moisture meter)

This means it is much more dry than the soil out of the bag.

I watered them both with 125ml water but used a spray bottle to water instead of just dumping it all in at once. Water was just starting to come out the bottom of the pots.

When watered they weighted 263 grams (6 on moisture meter, 7.5 soil ph on the ph meter).

Does this mean they were under watered?

Humidity in the room is really low (26%) as the humidifier ran out of water. Temp was 70 deg F (21 deg F). I wonder if the low humidity in the room is causing the soil to dry out so fast?

Below is a pic of the seedling itself, there is growth from yesterday. It looks a little purple on the ends though, this is taken under regular light, not the purple grow light.



Any help would be appreciated. Kind of feel pretty stupid not being able to get the watering part figured out. It should be the easiest part.

The pots are called root maker pots with a stepped bottoms and open air at the bottom of each step. It's supposed to help the roots grow and avoid the plant being root bound in the pot. Similar to a large fabric pot.

 

[Emilya Green]

Hi @DjEclipse and welcome to the forum!
First. lets address proper watering. Watering your soil is an art, and one that can not be done too rapidly because you should be attempting to slowly add water like you were adding it to a sponge, trying to get it to hold the most water possible before it simply can't hold any more (it is saturated) and any extra will come out of the bottom as runoff. Then to be totally sure you have all the soil can hold, come back again in 20 minutes and attempt to add even more water, until it starts coming out of the bottom again. Now you can be assured that you have watered your soil.
Then it is time to wait, until your plant has used ALL of that water before you water again. Think of that water sitting in the soil as a lake, who's surface keeps dropping lower and lower as the plant uses the water. The surface of that lake forms a perfect diaphragm that as it falls, pulls oxygen deep down into the soil. The roots need oxygen as much as they need water and they need that water table to fall down into the last inch or so of the container before you saturate that soil again. Here is where your water meter comes in. This highly inaccurate measuring device has one valid reading... WET. It basically reads MOIST until you push it far enough down into the soil that it hits the surface of the water table, and then it pegs all the way to the right and says it is wet. This is really all that this meter can do for you, is measure where the top of the water table has fallen to, and by measuring this you can get a very good idea of the plant's daily water usage.
So wait for that water table to get all the way to the last inch of container. You will surely think you are killing your plant. If you lift the container up, it will feel as light as air. The soil will be contracting in from the sides and will seem as dry as the sahara, yet your plant will not be drooping. When your human senses can not feel any water weight, and your meter says the water table has dropped, fully water again.
This is what is known as establishing a wet/dry cycle. The weeds love it, and they seem to thrive in a little bit of adversity... it is what weeds do. At first your wet dry cycle will be 5-7 days, but on each proper watering you will notice that the cycle gets shorter and shorter. When the roots have gotten large and strong enough to drain that container in 24-48 hours, it is time to uppot, to a container around 3x this size, and then start this process over again. The wet/dry cycle is your key to developing a strong root ball.
I wrote a nice article on how to properly water that goes into a lot more detail than this, and I invite you to read it. The link is in my signature lines below. Also, while you are looking around at my stuff, find in my links and tutorials an article on how much water our soil really holds.... the visual is very instructive.
Good luck, and as always, I will happy to answer any further questions after you have been familiarized with my theories. I think after reading these entire threads, you will completely understand how to properly water a weed.

 

[DjEclipse]

Thank you for the reply and detailed explanation of proper watering. I will follow this going forward. I was definitely not watering properly at all. Your explanation is ways to understand and makes sense.

I went in 12 hours later to weigh the pots and see how much water has been used (or evaporated). I have the control pot that is just filled with fresh soil so I can determine how much has been evaporated due to the low humidity and how much was used (or assumed to be used by the plant).

The control pot with just soil out of the bag weighted 183 g, now weight's 143 g = 40g evaporated.

Pot 1 water weight 263g - 203g today's weight = 60g - 40g evaporated = 20g used by the plant.
Pot 2 water weight 268g - 221g today's weight = 47g - 40g evaporated = 7g used by the plant.

Pot 1 is the one that is wilting the most so maybe it was really under watered and that is why it used so much?

Pot 1 is showing some yellow on the tips of the leaves.
Pot 2 is not drooping as much as pot 1 and doesn't seem to have any yellowing.

I am measuring 23,000 lux at the leaves if this matters at all. I don't have a par meter, they are rather costly. Lux meter is on my phone.

For those looking to read Emilya's original how to water watering thread it can be found here.

The Proper Way To Water A Potted Plant

 

[Emilya Green]

I love the true scientific approach. Other than cell phones being very bad at measuring light, it does give you a reference. A decent meter to read LUX does not cost a lot and really can help you "dial it in." Here is a chart I made of my new COB array's output, but I give it here so you can see the recommended LUX per growth period.

 

[Momma's Kitchen]

I love the true scientific approach. Other than cell phones being very bad at measuring light, it does give you a reference. A decent meter to read LUX does not cost a lot and really can help you "dial it in." Here is a chart I made of my new COB array's output, but I give it here so you can see the recommended LUX per growth period.

Congrats on Journal of the month!!!

 

[Emilya Green]

Congrats on Journal of the month!!!

Thank you Momma!

 

[DjEclipse]

Pot one is still drooping but looks to be drooping slightly less. Pot 2 is looking better as well, still drooping a little though. The stems are still strong, not drooping just the 2 leaves.

I watered again today, pots were around 150 grams, control pot was 100 (as it started out at 183g).
I watered with 125ml of water, all 3 pots.

Control 196g
Pot 1 =250
Pot 2 = 263

I watered with spray bottle until waster was coming out the bottom but when I put in the moisture meter it isn't show any moisture no matter how low I put the meter. Should I go back in 20min and water again with another maybe 100ml? The weight of the pots is close to what it was when I last watered 3 days ago. I just don't want to over water.


LUX Chart
It looks like you were graphing lux out output at different height's and the power draw for each output so you can see consumption and possibly save money on electricity at the beginning stages.

Judging by the zones you have on the chart it looks like I only need 5000 lux at my current stage. I am reading 22,000lux. Light is 24" away from top of leaves which is what the manufacturer of the light recommends.

As far as the lux goes how inaccurate is the phone lux meters? If it is accurate I am way too high lux wise and should move the light nigher right now?

Could the drooping be due to too much light? I am doing 18 on, 6 off light cycle.


Thanks again.