For the past few weeks the leaves on my two plants have been dying. They are only the bottom leaves but it is slowly working it's way up the plant. The new growth is perfectly fine. The growth hasn't slowed at all either. They are 6 weeks old and about 32". They have been flowering for 2 weeks now. I have 6,200 lumens of MH light shining on them. I'm growing them in soil and since the last watering used a fertilizer with a NPK ratio of 15-35-15. I used it at 1/8 the normal strength. The temperature is constant at 85 degrees. I tried to take a picture of the dying leaves but it kept coming out blurry. They start out by getting tons of little browns spots all over the surface. Then they turn pale green in color and still have the spots. After that the tips curl up and turn brown. Then the leaf falls off but it's not completely brown and dry. If this continues...they won't make it to harvest . Please help.
Try and reduce your temperature to below 80 degrees. Plus lay of the fertiliser and give them plain water for a week or two. Brown spots on the leaves is often nutrient burn. When flowering a lot of the older leaves will die of this is natural.
this has been happening weeks before adding fertilizer. It was the only reason I started using it...I thought that maybe it was deficeny in something so I added a little. It hasn't done anything for me though.
Nutrient burn begins with the edges of the leaves turning brown followed by the tips so thats not your prob.Spots all over the leaves followed by necrosis/leaves curling up and dieing off of entire leaf is a Mg deficiency.
the medium that I'm using said that it was a soilless mix...if that matters. It's made out of like bark and other plant materials or something like that. The soil has a slow release fertilizer but it is only .06-.03-.03 so I doubt it has much of anything else. Do you think I should try adding some more fertilizer and maybe make it a little stronger this time?
Why not try maxicrop seaweed extract this helps with nutrient uptake and your not risking overfertilisation.
Not all soil contains the amounts of Mg that mj sucks up and mg is the #1 deficiency most growers run into.I would try 1 tblspoon of epsom salts per gallon of water and see if things clear up as over ferting doesnt creat spots but a mg deficiency will with the tips curling as you stated.
Okay...thanx guys...I'll try the epsom salts. I did try some more fertilizer but nothing happened. They are still dying at the same rate.
ooohhhh....I just checked my fertilizer and it has everything BUT Mg. I'll let you guys know what happened with the epsom salts after I do it.
No no more fertiliser. I'd try the epsom salts then no more fertiliser. Have you got another picture?
I will put up another pic soon...gotta charge my camera batteries. The epsom salts seemed to have done the trick. The leaves are pretty much maintaining their color now. The plants are about 4 feet tall and the new growth seems great. The flower growth never slowed during the leaf death so I'm still not sure if it was a normal part of flowering or a just a deficency. Whatever it was, it seems to be ending now. They've only been flowering about 3 weeks so far.Thanx for the help guys.
No it wont effect ph but excessive Mg can lock out K,Zn,B,and Mn as well as interfere with soil structure making it gummy(sticky).Growing with soil of poor structure or drainage probs are usually the ones effected by excessive Mg which compound probs. Glad to here your plants are better TG.
Big time magnesium deficiency. Look at the older leaves. Green veins. Yellow intervienal chlorosis. Text book. Her biggest problem though is that there is no calcium. A good soil needs 1 part potassium, 3 parts magnesium and 10 parts calcium. Oh weedhoppers.....
