Yellowing of the leaves with Brown spots

[Geraldo LaForge]

Hello everyone: Geraldo LaForge speaking:

For about a month my plants were great, now I'm slowly trimming off leaves due to a problem affecting nearly all the plants.

I've looked at some of the other threads but haven't been able to narrow it down to one problem. The plants receive 18/6 hours of T5 FL light and now the temperature is about 21-23^Celsius. For awhile, I thought it might be low temperatures, but I've added a heat source and the temperature is back in the green zone. The heat source is still new so I can't tell yet if it was the cause.

I keep the plants moist and I feed the plants about once a week. It's a low 7/6/6 solution. I'm thinking it may be a Magnesium deficiency, but I was pretty sure my soil came with 5% or so potash. I've also Ph tested my soil and it is about 6.2

 

[CARLOS BLANCO]

hope sum1 helps you out cuz i got the same problem.. I was underwatering them for the first 3weeks and then i started to see these brown spots.. and i think it was because i was using very high pH. and i wasnt watering them often. Ima start feeding them daily with sum wetting agent mixed with the nutes.. If they start to get better in a week then that means that they werent getting enough nutes. and it was most likely a magnesium or iron deficiency.

 

[Purplekrunchie]

First of all, don't trim these, the reason the leaves are doing this is because the plant is using what it needs from them. Trimming will cause the plant to get worse real fast, it does look like a mag deficiency, provided the plants have been given calcium, you can use epsom salt diluted 1 tbsp per gallon of water for magnesium. Magnesium needs calcium to work properly, so make sure it has that too. But again, never trim off leaves that appear that they are being sapped, they are helping your plant, and buying you time to remedy the situation.

 

[*BUDS]

Hello everyone: Geraldo LaForge speaking:

For about a month my plants were great, now I'm slowly trimming off leaves due to a problem affecting nearly all the plants.

I've looked at some of the other threads but haven't been able to narrow it down to one problem. The plants receive 18/6 hours of T5 FL light and now the temperature is about 21-23^Celsius. For awhile, I thought it might be low temperatures, but I've added a heat source and the temperature is back in the green zone. The heat source is still new so I can't tell yet if it was the cause.

I keep the plants moist and I feed the plants about once a week. It's a low 7/6/6 solution. I'm thinking it may be a Magnesium deficiency, but I was pretty sure my soil came with 5% or so potash. I've also Ph tested my soil and it is about 6.2

View attachment 1333410

overwatered -let medium dry more between waterings.Temps are cool in there so not much soil evaporation.
and potash is pottasium not Mg

 

[Geraldo LaForge]

First of all, don't trim these, the reason the leaves are doing this is because the plant is using what it needs from them. Trimming will cause the plant to get worse real fast, it does look like a mag deficiency, provided the plants have been given calcium, you can use epsom salt diluted 1 tbsp per gallon of water for magnesium. Magnesium needs calcium to work properly, so make sure it has that too. But again, never trim off leaves that appear that they are being sapped, they are helping your plant, and buying you time to remedy the situation.

Thanks for the info. I won't trim anymore. Luckily, I haven't trimmed very many.

overwatered -let medium dry more between waterings.Temps are cool in there so not much soil evaporation.
and potash is pottasium not Mg

This could be possible. I'll cut back on how much I water and see what happens. Thank you.