Brown Spots and yellow leaves! Help!

Maer

New Member
I have read the plant trouble shooter list and I have come up with my own ideas but wanted some second opinions. Here are the details:

Soil: FFOF
pH: little low at 6.1
Temps max out at 90, but most times around 85
Humidity is low around 30% lights on 40-50 lights off
Feeding with Fox farm organic trio every other watering
They are about 6 weeks of veg, because I am waiting for a second flower light to flip to flowering

Below is my troubleshooting:

Looked everywhere for bugs. no signs at all.

lower leaves yellowing = nitrogen deficient?

Fringe brown = Potassium deficient? Calcium deficient? Nute burn?
Heat stress?

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Hogdady

Plant of the Month: June 2010 - Nug of the Month: July 2010
The dolomite (powdered) will maintain a stable soil ph (important), and you can mix it into the topsoil (1/4 cup per gallon of pot size) and it will leach down. It also has some cal/mag in it.

I always had some yellow lower leaves until I started adding guano (mexican). Since then all of my veg growth is robust and green. They like the nitrogen in veg.

You can foliar spray some dissolved epsom salts to bump up the magnesium and then supplement with cal/mag. If you mix in dolomite to your soil before use, it will have enough cal/mag in it.
 

Maer

New Member
So is it OK to add my FF nutes and some of this mexican bat guano? I found it online pretty cheap like 4$ for a 1lb bag, do I dissolve it in water? How much bat guano for my 3gal pots? How much Epson salts per gallon of water? This is only happening on 2 of my plants, even though they are all identical genetics and soil / nutes, should I treat them all or just the 2 with this problem?

Thanks for your help, I really appreciate it
 

Hogdady

Plant of the Month: June 2010 - Nug of the Month: July 2010
So is it OK to add my FF nutes and some of this mexican bat guano? I found it online pretty cheap like 4$ for a 1lb bag, do I dissolve it in water? How much bat guano for my 3gal pots? How much Epson salts per gallon of water? This is only happening on 2 of my plants, even though they are all identical genetics and soil / nutes, should I treat them all or just the 2 with this problem?

Thanks for your help, I really appreciate it

I use two cups guano and put in a sock. I put the sock in a five gallon bucket of water (ph'd) with a circulation pump (fish tank) and let it swirl for about an hour. Use this to water your plants when its time to feed. Once during veg is all I do.

1 tbsp per gallon (dissolves better with hot water) and only spray the ones with the symptoms.
 

Maer

New Member
Cool man thanks again for all your help. I just got epsoM salt from the pharmacy and "Espoma Garden Lime" which says is the "finest grade of dolomitic limestone available" so I think this is the stuff. The analysis on the back says Calcium, Magnesium, Calcium Oxide, Magnesium Oxide, Calcium carbonate, Magnesium Carbonate, it that enough Cal / Mag? Or did you mean the commercial supplement by Botanicare?

Amazon.com: Botanicare CAL-MAG Plus Quart: Flora Hydroponics

Couldn't find an bat guano, but blood meal says its an organic nitrogen source, is that any good?

Again thanks for all the help I really appreciate it.
 

Hogdady

Plant of the Month: June 2010 - Nug of the Month: July 2010

Maer

New Member
I got my guano and Cal / Mag today in the mail. I have mixed the dolomite lime in the top 3-4 inches of soil and have sprayed maybe 3-4 times with epsom salts. They seem to be recovering, so should I still treat them with the Cal / Mag, if so at what strength? Follow the bottle, half strength ect? Should I stop spraying with epsom now?
 

Hogdady

Plant of the Month: June 2010 - Nug of the Month: July 2010
Sounds good! You can stop the epsom salts now and just go 1/2 strength with the cal/mag now that you have some dolomite in it.

If you are going to veg some more, you can add the guano as soon as they have some good, green new growth. If you are going to flower, skip the guano.

There are two types of guano, one fron insect-eating bats (mexican), that is high in nitrogen, and one from fruit-eating bats (peruvian) that is high in phosphorus. Plants need plenty of nitrogen in veg, but not much in flower. Vice-versa with the phosphorus.

Good grow to ya! :)
 

Maer

New Member
Yea I'm flipping so i guess I will skip the guano, its Mexican guano. Should i get some Peruvian for the flowering girls or will the FF trio be enough?

I have a second batch of 6 that are in veg so maybe I will feed them some guano.

Thanks for all your help HD
 

Santurro99

New Member
I have a very similar thing going on with one of my ladies. Unfortunately I only have the ph tester kit to go off of so I am sure my problem is due to ph lockout of some sort. Ive been using my tap water which I oxygenate for 24 hours. Ph seems to be about 8 and I was using it for a couple weeks before I knew that. I was told that it is most likely cal/mag deficiency due to the high ph and was told to add cal/mag to just water. I added a few drops of ph down to try to lower the ph of the soil. I will let you know if it helps any. I am also interested in the bat guano thing so I will stay tuned.
 
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