Popping seeds with HID MH 1000W...what is my safest option?

[jakieemma]

I asked a similar question in another thread but have done some experimenting with lights and have come to this problem.

I'm in the process of germinating my feminised WW seeds. I started them about 20 hours ago using paper towels in a blacked out tupperware container. I snuck a quick peek this morning to find a couple have already cracked and a very immature tail root has appeared. I only looked quickly, in the dark and examined a couple to see if they were moist and warm, so far, so good.

I am using FF soil and starting the seedlings in a 1 gallon pot. I plan on transferring them into a 3.8 gallon pot after root growth. I am growwing 8 WW in a 4x5x7 closet. My lighting is a 1000w adjustable ballast with a glass encased, air cooled hood. I'm running a 400 CFM inline fan and exhuasting into the attic. I have no option to use CFLs or any other configuration, I am committed to this lamp.

Here is my question...I have read many things about seedlings under HID, both positive and negative. Some opinions sight temperature as a problem, others the amount of light or humidity.

I have decided 3 feet from the seedling is where I'd like to set the lamp to start off. So, I took temperatures at 3 feet with all 3 ballast settings and have found this:
At 3 feet, set at 50% power, I have steady temps at 71F
At 3 feet, set at 75% power, I have steady temps at 74F
At 3 feet, set 100% power, I have a steady temp at 80F
All temperatures were confirmed by placing 3 thermometers atop the pots (no soil yet) at 3 feet below the lamp. At all 3 settings I can place the back of my hand 6 inches from the lamp without burning. I am not too concerned with humidity yet as I know 8 plants and moist soil will provide adequate amounts of humidity to the closet.

So....what lampp setting and distance would you use? I believe all 3 temps are ok, but just not sure about the intensity of light for the first couple of weeks. I plan on slowly getting the lamp running at 100% and lowering the lamp height to about 18"-24", depending on plant growth.
Do you agree with my initial distance of 3 feet for the newly sprouted girls or is there a better strategy?
You are the pros, I await your constructive criticism.
Thanks in advance...

 

[CaretakerDad]

The best way to find out how close to your light to have your seedlings is to place your hand palm down at the height you want the top of your seedling or plant ( mine happens to be about 24" ). If the back of your hand is uncomfortable, your seedlings will be too warm. I know it sounds simple and lacks any sort of technical approach, but remember the K.I.S.S. principle and apply whenever practical. Below are three of my seedlings at 9 days from breaking ground under HID, notice how compact they are with 3 sets of true leaves already fully formed.







You can view my original sprout pics here https://www.rollitup.org/general-marijuana-growing/753575-hid-lamps-seedlings-2.html#post9849180


Be careful about heat build up and you should be fine. Good Luck, Larry

 

[Wavels]

No worries whatsoever in using HIDs to pop seeds.

I have started many seeds under the good old naked sun, as soon as the seeds emerge from the soil, they relish the abundant natural light.

Every alternative to the sun provides less light.

Hids and cfls and T-5s can only hurt your seedlings if the ambient temperature is too high.

 

[jakieemma]

They look great, thanks for the advice. So 100% power is fine as long as heat is not an issue?
Would you start them off at 50% or 75% or right to 100%?

What I'm gathering from both yours and Wavel's replies is that the main thing to worry about is heat, not light. I asume if I can run 100% with no heat issues, that would be optimum.

So, unless you say it's not a good plan, I'm going to start them out at 3 feet at 100% power. I will slowly lower the lamp over a few days and get the lamp to about 24" eventually.

Thanks again for any advice

 

[Wavels]

Yup, If at 100%, you have the temps in the low 80's, no worries , have fun watching them grow!

 

[CaretakerDad]

Don't go by height, use the force Luke....or the back of your hand. My own humble opinion is that you cannot mimic the power of the suns light so there is no such thing as too much light ( up to the maximum absorption capacity of the plant ) as long as you remove the heat. Find out what height is comfortable in your setup and monitor it closely and adjust frequently if necessary depending on growth. You are running a cooled hood and I am not so you may be able to get your light closer. With artificial light the intensity drops off dramatically even with small differences in the distance. Somewhere here on RIU there are light intensity charts that may help you understand the importance of light distance vs intensity. Happy Growing, Larry

 

[Wavels]

, use the force Luke....or the back of your hand. My own humble opinion is that you cannot mimic the power of the suns light so there is no such thing as too much light

That is the secret in a nutshell...bravo.

Take the time to get to know your plants and all will be well.

 

[jakieemma]

Thank you all for the great advice. I am excited as 7 of the 8 have sprouted with a about 1/4" tails after 30 hours. The last to pop is the Northern Light I got as a freebee. I plan on planting in about 12 more hours. Hopefully the last seed will crack by then and I can plant all 8 at the same time. Thanks again.

 

[banks dank]

I asked a similar question in another thread but have done some experimenting with lights and have come to this problem.

I'm in the process of germinating my feminised WW seeds. I started them about 20 hours ago using paper towels in a blacked out tupperware container. I snuck a quick peek this morning to find a couple have already cracked and a very immature tail root has appeared. I only looked quickly, in the dark and examined a couple to see if they were moist and warm, so far, so good.

I am using FF soil and starting the seedlings in a 1 gallon pot. I plan on transferring them into a 3.8 gallon pot after root growth. I am growwing 8 WW in a 4x5x7 closet. My lighting is a 1000w adjustable ballast with a glass encased, air cooled hood. I'm running a 400 CFM inline fan and exhuasting into the attic. I have no option to use CFLs or any other configuration, I am committed to this lamp.

Here is my question...I have read many things about seedlings under HID, both positive and negative. Some opinions sight temperature as a problem, others the amount of light or humidity.

I have decided 3 feet from the seedling is where I'd like to set the lamp to start off. So, I took temperatures at 3 feet with all 3 ballast settings and have found this:
At 3 feet, set at 50% power, I have steady temps at 71F
At 3 feet, set at 75% power, I have steady temps at 74F
At 3 feet, set 100% power, I have a steady temp at 80F
All temperatures were confirmed by placing 3 thermometers atop the pots (no soil yet) at 3 feet below the lamp. At all 3 settings I can place the back of my hand 6 inches from the lamp without burning. I am not too concerned with humidity yet as I know 8 plants and moist soil will provide adequate amounts of humidity to the closet.

So....what lampp setting and distance would you use? I believe all 3 temps are ok, but just not sure about the intensity of light for the first couple of weeks. I plan on slowly getting the lamp running at 100% and lowering the lamp height to about 18"-24", depending on plant growth.
Do you agree with my initial distance of 3 feet for the newly sprouted girls or is there a better strategy?
You are the pros, I await your constructive criticism.
Thanks in advance...

Just use common sense bro its not rocket science...

 

[banks dank]

I asked a similar question in another thread but have done some experimenting with lights and have come to this problem.

I'm in the process of germinating my feminised WW seeds. I started them about 20 hours ago using paper towels in a blacked out tupperware container. I snuck a quick peek this morning to find a couple have already cracked and a very immature tail root has appeared. I only looked quickly, in the dark and examined a couple to see if they were moist and warm, so far, so good.

I am using FF soil and starting the seedlings in a 1 gallon pot. I plan on transferring them into a 3.8 gallon pot after root growth. I am growwing 8 WW in a 4x5x7 closet. My lighting is a 1000w adjustable ballast with a glass encased, air cooled hood. I'm running a 400 CFM inline fan and exhuasting into the attic. I have no option to use CFLs or any other configuration, I am committed to this lamp.

Here is my question...I have read many things about seedlings under HID, both positive and negative. Some opinions sight temperature as a problem, others the amount of light or humidity.

I have decided 3 feet from the seedling is where I'd like to set the lamp to start off. So, I took temperatures at 3 feet with all 3 ballast settings and have found this:
At 3 feet, set at 50% power, I have steady temps at 71F
At 3 feet, set at 75% power, I have steady temps at 74F
At 3 feet, set 100% power, I have a steady temp at 80F
All temperatures were confirmed by placing 3 thermometers atop the pots (no soil yet) at 3 feet below the lamp. At all 3 settings I can place the back of my hand 6 inches from the lamp without burning. I am not too concerned with humidity yet as I know 8 plants and moist soil will provide adequate amounts of humidity to the closet.

So....what lampp setting and distance would you use? I believe all 3 temps are ok, but just not sure about the intensity of light for the first couple of weeks. I plan on slowly getting the lamp running at 100% and lowering the lamp height to about 18"-24", depending on plant growth.
Do you agree with my initial distance of 3 feet for the newly sprouted girls or is there a better strategy?
You are the pros, I await your constructive criticism.
Thanks in advance...

I think your over complicating this. use common sense bro its not rocket science...