Ready for feeding? PICS

Hello all

I think my plants may be ready for their first feeding. This is based on the yellowed appearance of some of the new growth. They have been above ground for about 12 days. The soil is 50/50 by volume pre-fertilized potting soil and vermiculite. They are under 110w of daylight CFLs. I have been watering every 3-4 days. I have been misting daily, especially those without their second set of leaves.

Any advice would be appreciated. I know the soil mix was far from ideal and plan to change that when they transplant. I am considering fertilizing with 1/4 concentration Alaska fish emulsion because I am interpreting the yellowing to be a sign of nitrogen deficiency. Should I wait longer to avoid burning them?

Thanks

First picture is from this morning and the yellowing is most visible on the one in the lower left corner.

Second picture is from yesterday and is a blurry picture of an injured leaf (cause unknown).

Third picture is of the outside of the 2' x 3' x 5' grow box (shows vent fan and closet).

Fourth picture is the inside of the grow box (shows plants, circulation fan, passive intakes, thermometer, and timer. Lights are raised out of view.)

Fifth picture shows lights (3 x 30w Twister and 1 x 20w Twister CFLs in a clamp lamp) lowered to normal distance from plants.

negative sir.

Do not feed until your plants have 5 nodes. Feeding any soonder then this will result in a very angry/dieing plant. The yellowing you're seeing is probably burn from the pre-added ferts and emulsion.

serious? i was soo about to say the oposite... i personally have always started to fert mine as they break surface. (keep in mind tho id use a 1/2 dosage of miracle gro at 3drps/litre)

i figure plants will love nuts at any point. just watch the od in seedlings, since theyre still fragile

My friend always starts his earlier. As soon as they receive their first set of true leaves and begin photosynthesizing, he begins administering a low-concentration nutrient solution. He typically begins at about a 10% solution, then 25%, then 50%. He will continue at a half-strength solution until they are transplanted into larger containers.

I've followed the practice of waiting until the two seed leaves die off before fertilizing. This makes sense because the plant is essentially growing off the nutrients provided by the seed until all nutrients are used up. By fertilizing you're just adding even more nutrients into the soil when the plant isn't using them and will lead to problems later.

Well as you can see everyone else has different theories. The popular one (or atleast seems popular on the boards as its the one i read the most) is don't fert until you've got 5 leaf nodes.

what kinda nutes should ya use, as in, im goin to the store in an hour. what would i look for?

sorry to go off topic, but where could i find nitrogen for soil. my leaves are still yellow at the bottom.

The rule of thumb is when the 5th node is starting. You shouldn't go by the cotyledons turning yellow because some plants grow very large and keep them nice and green.

Typically, its the 5th node, however, each strain is different, you have to watch your plants, they will tell you when they are hungry. Now with that being said, you need to get those main stems a little more 'bulky' to support the plant. I see that you have a fan in there, but it looks like that the air movement is missing your plants and that is why you have to keep them posted up. First thing i would do is to get those stems thicker, and at the 4-5th node, or when your plants are starting to show signs of nute def, then you add the nutes. Sending a plant into a lockout at early age will result in hermie, male plants, and i dont think thats what your looking for.....i could be wrong tho.

i give my plants all the nutes they want in small increments, until the first sign of burn near the bottom. at that point, i flush VERY LIGHTLY and keep it at that nut level till theyre used up.