same problems

any1 know what causes a plant to grow extremely slow even when the temps, humid, and ph and ec and all the other stuff are fine.. 2nd failed grow now and cant take much more. using a 600w hps and 250w mh in soil. 5 weeks old and barely 4 inches tall with only 1 main stem and 2 sets of leaves. have put a post on general growing as well but no 1 there can figure it out.. many thanks

Phosphorous deficiency!! I had 4 plants and 1 was literally growing half as slow. No signs of deficiency.. just all started same height and that one turned out slow. I looked it up on google and used deficiency charts.. found out phosphorous causes that. Added phosphorous and now it is as tall ss the others. 12 hours after adding it the top half of plant got way bigger.. dwarfing the bottom half. Now the bottom half caught up. The only difference I notice is the nodes are waaaay closer together now than on the other 3. Possible way to manipulate/train? Like wondering how many licks to the center of a tootsie pop.. the world may never know!! And potheads who do may forget from short term memory loss.

please list what medium (soil, coco, rockwool) you use as well as nutrients. You say temps are between 70 and 80?

thanks for the reply, iam using part seed and cutting compost, part perilite and a bit if sand and hydrotn balls to help drainage, my day temps are 27c and 22c at night using bio bizz grow and bloom thats all, but i havent used it yet as they arent showing any difficiencies must still be nutes in the soil. 1 of them is going a very light green compared to the rest other than that they look healthy just very small. what could you add to try and help.. many thanks

How big are the pots and how often do you water?

Leaves board flat or droopy/curved?

no curling on leaves there only in 5 litre pots as the roots are far from bound, water every 3 days.

I highly doubt a plant that small (especially one that isnt growing!) is drying out a thoroughly watered 5 liter pot every three days. I think your problem may be related to overwatering. Overwatering can really stunt your root growth, and without healthy roots, there will be minimal growth. Usually you would see some other symptoms along with the slow growth (drooping, yellowing, etc), but not always.

It's possible you just got a bad seed... Maybe it's time to cut your losses and try again.

Maybe try adding some Phosphorous and wait 3 days before trashing. But stunted growth is a deficiency sign for phosphorous.

thanks rob0769, it must be that as they are definately not overwatered i wait as i have been told until the soils dry a good 2 or 3 inches below the surface, they need watered every 3 or 4 days because the drainage is very good, the bio bizz grow only has 2% phosphorus in it so i will try using a wee bit of miracle grow which has 8% phosphorus. the seeds were from dutch passion feminized brainstorm, but ive had the same results with ghs seeds as well. dont thinks its the seeds either, the only clue i have is the phosphorus if its not that then i dont know what to do.. thanks all

General Hydro Kool Bloom powder at .2 tsp a gallon fixed my stunted plant. Dunno if you're trying to stay all organic or if miracle grow is organic. Let me know how it turns out.

try getting some earthworm castings and taking a handful throw it in a 5 gallon bucket fill it with water and a couple of table spoons of molasses. let sit for 3-5 days stirring everyday then use on plants soil drench and spray them the plants will love you for it

will try a wee bit of miracle grow as its near hand, use bone meal from start to finish on the next grow. but i think iam already seeing an improvement. fingers crossed.