I just noticed one of my plants leaves have started turning a rusty brown looking color. Only the fan leaves in the middle of the plant have any brown on them. All new growth and leaves at bottom look healthy. I’m growing in foxfarm happy frog soil in a 1 gallon fabric pot. Been feeding with foxfarm nutrients as well. 5 other plants with same conditions are fine
Leaves turning a rusty brown color... help
- Thread starter Chop456
- Start date
Do you use cal mag?
Yes
Hydrotech364
Well-Known Member
Is light getting to those leaves?
Dr.J20
Well-Known Member
Could be the specific response of that plant, could be something else. How old are they? Whats your temp? RH? whats pH at feeding?
I don't usually weigh in on salt based fertilizer shit because I could never make it work for me. My guess is she's showing a some kind of nutrient lockout issue related to the soil pH. I'm not sure if they still recommend flushing in this style of growing--its a real shame to have to use all that water. I think the common advice here is flush and feed half to quarter strength nutes.
Or you could go sub irrigated organic and just watch em grow--but I digress...
I think it's unlikely you've got a deficiency of anything--what kind of feeding schedule are you on? If you can rule out deficiency, then are there any overabundances that you could be showing? Depending again on your feeding schedule, this is probably unlikely. It looks a bit like a calcium-magnesium issue, but it could also look a little like phosphorous deficiency.
A pH imbalance could cause this appearance by making it impossible for the plant to take up the phosphorous. People often recommend the cal-mag solution for this. I never got the hang of cal-mag (either), but a quarter cup per gallon of soil dolomite lime works well scratched in to the top couple of inches, that will help you keep your soil in the right pH range and ads some calcium back to your mix. Epsom salts will get you the magnesium if you really think there's a deficiency-- again, scratched in to the top couple of inches of soil, better if you throw a handful in the transplant hole before you transplant, but no big deal top dressed. The dolomite lime will help adjust the soil pH for a longer period of time, which might mean you won't need to use as much cal-mag any more. It's also worth checking out the quality of your water to see what the calcium is there. She might just be the first one showing the signs, a harbinger of whats to come for the others.
Good luck, be easy,
xtsho
Well-Known Member
I see more problems with people using FoxFarms nutrients than any other. That's because if people follow their feeding chart they overfeed their plants. You don't have a deficiency issue from lack of nutrients. You have a deficiency issue from overfeeding that leads to nutrient antagonism.
It's not pH. You don't need CalMag. You need to cut the nutrient strength back.
It's not pH. You don't need CalMag. You need to cut the nutrient strength back.
So beginning of nutrient lockout? Should I flush or just cut back?
xtsho
Well-Known Member
Cut back. Plain water for a minute.
Thanks
70° at night 75-76° during daytime
Humidity stays right around 50
I have temps and humidity dialed in