seedlings are having problems turning yellow

[Guest]

2x2x4' (ft). cab - 250W air cooled MH connected directly to a 4" vortex

they're in 3" peat cups, with just regular peat foss (i believe) germination soil without any nutrients.

I know they shouldn't be under this light, the light is 2' (ft.) away, but i've read people using HID's from the beginning. (i just moved the light to 30.5" in.)I check on them twice a day, but due to the heat and these peat cups they dry up real quick so I water twice a day - once in the morning and once at night, just a little bit to make sure they stay moist. My last seedling died under 2 - 30W CFL's, since cups dried up (it's what I was told from this site), I was watering every 3 days. So, I decided to just put them under HID and just water more frequently, they've been under the light for a few weeks (i guess, don't know exactly, should've wrote it down, planted seed directly into soil), so I guess it's ok to just keep them in there? although leaves are turning yellow so I'm concerned. also one of the bottom leaves has some kind of dark spot, don't know what that's from.

 

[dan kay]

what's the size of those pots?
how do you tell if they are dry?
have you used any nutes?
what's your water pH?
what's the temprature at the top of the plants?

 

[Guest]

what's the size of those pots?
how do you tell if they are dry?
have you used any nutes?
what's your water pH?
what's the temprature at the top of the plants?

3" pots, just put one of them in a 1.25 qt. pot so I can water less, I used fox farms ocean forest, I think it's going to shock the plant, since OF is very strong. I'll see how it does and if it shocks the plant, I'll put the 2nd seedling into the same regular germination soil instead of OF.

haven't used any nutes

you can tell from the cup itself if it's dry since when you water it these peat cups are like cardboard and get very stiff when they're dry , and the top of the soil is dry.

not sure about water ph, haven't checked that in the beginning used tap water and distilled water then switched to spring water and now distilled water.

not sure about temp. at top of the plant, but the bottom of the cab varies, 74-80 degrees

 

[dan kay]

did you see any roots when you transplanted? with those pots that the soil can dry out from the sides all the way down its possible the sides were all dry but the middle was still moist.

 

[Guest]

so you think they're turning yellow from too much water?

 

[Guest]

i didn't pay attention to the roots when I transplanted

 

[MynameStitch]

your soil your using is first to strong for seedlings but that will most likley be your next problem
you should use a seedling mixture for a week or 2 then transplant into fox farm

also how often ar you watering your soil looks like its saturated

the roots on that seedling are not big enough to absorb all that water the yellowing is caused by overwatering and its lacking o2 causing the plants to loose nitrogen
nitrogen is poorly abosrbed in soggy soils

most likley in order to save them you will need to get them out of that soil
are those peat pots your using?

 

[Guest]

yeah peat pots, and one of them is in a seedling mixture, the other one has been transplanted into fox farms after it's been 2 weeks+ since it's sprouted, they're growing real slow. i'll water less and see what happens, they just dry up real quick with that light and those peat cups. i've been watering twice a day. i'll go to every 2-3 days and see what happens.

 

[br26]

i don't use the mini peat pots for the reason of them drying out with the youngins. i would agree with Mynameisstitch, when using another seedling mix until you transplant again. make sure the seedling soil is near the same components beside the nutrient addatives. i usually get fert burns in the beggining, if starting from this soil. keep the humidity up too, this will help out the seedlings.

 

[Guest]

i don't use the mini peat pots for the reason of them drying out with the youngins. i would agree with Mynameisstitch, when using another seedling mix until you transplant again. make sure the seedling soil is near the same components beside the nutrient addatives. i usually get fert burns in the beggining, if starting from this soil. keep the humidity up too, this will help out the seedlings.

my humidity is really low around 24% what can I do to increase this?

 

[MynameStitch]

humidifiers or wet towels in a pan or a pan of water around yiour seedlings will help bring the humidity up

do not use peat pots they cause more problems than what its worth
they are acidic for one and i would just get a pot for them

 

[br26]

A cool mist humidifier would be a good idea, with a fine mist. You can get either filter or filterless, and i've only had experience with the ones without. The last one i purchased from a common mart, was supposedly a cool mist humidifier, but was a fan over a bowl of water. It was useless. The description said "if the humidifier is not producing a mist, it is working." Returned that the next day. I did pick one up from the 80's. It is better than the ones you can get nowadays, but was sold in these stores.

Just remember to use clean water when using them. Either distilled or RO water should go in it. Clean it often also.

 

[Guest]

alright I changed the 2nd seedling from a peat pot to a plastic cup, hopefully that wont' dry out as quick, and i've increased humidity to about 33% all I did was add a small fan inside and a 16" fan outside except my temps increasted to 84

 

[Guest]

did you see any roots when you transplanted? with those pots that the soil can dry out from the sides all the way down its possible the sides were all dry but the middle was still moist.

yeah, on the 2nd seedling that was transplanted, I saw roots, and you were right all of the soil was moist

 

[br26]

why are your temps soo high?

do you have cold air coming in to the cab?