miracle gro, yellow leaves, not enough nutes or too much?

This is our 5th attempt at growing, we've failed all other attempts. :( With our hydro system we use the nutes that come with the damn thing and the instructions say to put 1 teaspoon per gallon of water for each of these two things, bloom and grow or something. So we did that and failed because the leaves would eventually turn all yellow. We attempted in soil and found similar results, I guess since in soil we didn't use any nutrients at all other than what comes in plain potting soil, they didn't have enough nutrients.

Now we bought some better soil and the plants have been looking so beautiful. It looked like they started to get light color and showing signs of needing fertilizer so I used Miracle Gro 15 - 30 - 15. I used it a little weaker than it says, about 3/4 strength. Right away we were wowed by seeing what we thought was some positive growth after feeding the plant some miracle grow. About a week went by and I kept seeing the yellow come, so I assumed I didn't put enough nutrients. I used the miracle grow again and waited. I continued to see yellow so I looked in our book and saw that yellow leaves are a sign of nutrient burn. I quickly flushed the plants for a few days with regular water. We cut the yellow leaves off and continued to water. It seems about 2 weeks went by without watering and although they're still doing relatively well and getting taller, and thicker, the yellow seems like it's getting worse. So today my girlfriend fed them some miracle gro since she says it's been a couple weeks of just water and she thinks the yellow is lack of nutrients.

These plants are probably 5 weeks old and looking beautiful, except as time goes on I see more and more yellow and we have to cut more and more leaves. The pots are probably like 6" pots if that matters. We're using a 430 watt San Agro lamp that seems to be doing just fine. I took this pic with my phone and apparently high light intensity makes it look shitty I guess because otherwise this 2 mp cam works incredible.

Thanks in advance for any tips, advice, criticism, etc.

Anyone? I guess everyone is probably asking the same question that I'm asking myself, is it too much nutrients causing the yellowing or not enough. :)

I'm pretty sure the prob. is the MG or pH. I believe MG lacks micro-nutes. Get some Peters All Purpose. That is what I used when I grew in soil. Don't forget to flush that MG out before you start using the Peters. Also get a cheap pH tester and read up on the importance of pH. Actually I would check the pH first, because without it being correct nutes are no good anyway.But I would still 86 the MG.
Also pH is VERY important in hydro. I would bet that is where you failed with it.
You would be suprised at the amount of useful info there is on this fourm if you took the time to search, read and ask before starting to grow.
I wish you luck on this and your future grows.
Peace Out :hippy:

Thanks for replying man. I have searched the forums and have learned that some people like Miracle gro and some don't. Some use it some don't. I've read that if you use it full strength it can burn the leaves, but we haven't been doing that. I also read in several places that it can be lack of nutrients. I did attempt to research this but am looking for more experience. Thanks a lot, I'll invest in a PH tester!! :)

And the pH of your run-off water should be around 6.5. If your pH is out of range it will lock out nutrients causing a deficiancy. So adding more nutes would then cause more problems. So check that pH before you give any more nutes and get it fixed if out of range. I bet your watering them with tap water that has a high pH. A bottle of pH down is like 8 bucks at the hydro shop.Or if you don't want to mess with pH down the RO water I get out of the machines is right at 6.6, which would be close enough. :jointsmile:

Start in small pots and transplant 1-2 times to avoid becoming root bound. Pot size: 1 gallon per foot. So 3 foot tall plant = 3 gallon pot. Superthrive (avail. at Wally World, Home DePOT, etc.) is very good for transplanting.

without seeing your plants, I will go out on a limb, and suggest you are over-watering ... the plant MUST go thru wet-and-dry cycles ... probably the most common mistake growers make ... over-watered, and under-watered plants, look about the same, drooped, sagging, etc... overwatering also yellows the leaves, later they fall off ... :smokin:

yellow leaves is not a sign of nutrient burn for starters, and while it could be caused by several things from a deficiency or ph problems or lack of light.
would probably keep feeding them atleast every other watering and chances are they may very well come out of it, if its a simple nitrogen deficiency, but it might be a good idea to find out the ph of your soil and maybe try a better brand of fertilizer just incase you continue to have problems.