hi all... i am a beginner growing under 400w mh lights. im sorry i dont have any pics, i will get my camera up here soon. any way i have 6 plants going that are 2 weeks old. they have been looking really really healthy and green. about 2 days ago though, 2 of my plants started showing yellow tips on the leaves, and this morning one of the plants turned even more yellow. i have them in 1 1/2 gal. pots. soil mix. no fert. yet. any ideas??
check your pH of the soil, it should be around 6.5-7. If ithe pH is too high it inhibits the plants ability to use nutrients. Also, you may have some kind of nutrient deficiency. Mix up a little bit of dyna gro and it should fix it.
thanks... the soil i have has very low nutrients...like .011-.10-.10 i think. is it too soon to start feeding it nutrients though?
Wait a minute here before you jump and do the wrong thing. first what kind of soil are you using??? Soil usually does not need any nutrients what so ever unless you using plain dried out dirt from outside, if the soil is dark in color nutes should be fine. First thing you need to check is the soil itself, its PH and its consistency, many times soil will get muddy/sticky and not let out water very well and keep air out, thereby starving the plant of oxygen to the roots and you get root rot. So check that first Second is the water your using, if its tap water, you better make sure the PH is between 6.5 and 7. you could also be overwatering the plant but you will know this when you inspect the soil, if its mushy and sticky like clay repot it in some good soil. refer to my post in the outdoor grow section (Xmas trees St. Maarten Style) for the soil mixture i use.. Using potting soil alone will not cut it. DO NOT USE MIRICLE GROW UNLESS YOU WANNA KILL YOUR PLANT!
The soil you use should have no fertilizer in it; especially time release crap. The HID light will speed up the release process and over fertilize your young plants. If there are no nutrients in your soil, now is the time to invest in some good vegging plant food which can be N30-P30-K30. I use 20-06-16 for vegging. You can probably feed them now after they are a few weeks old. Go real easy though on that and mix with water only half or quarter strength to start. As Dier said, do not use Miricle Grow.
Thank you both for your advice. im still trying to get a decent camera to up some pics. The one plant that was worse is now almost completely yellow and shriveled up. most of the others are starting to get yellow tips also and they all have the 2 very bottome leaves yellow. the potting mix i have is dark in color so im not sure whether or not to add nutrients. i have a nute tester for NPK but am unsure at what level the soil should be? i'll wait to get nutes till i find out how much the soil should have.
any plant sitting in wet soggy pots that dont drain will go yellow. I think over watering is a major problem for most people. So is over feeding.