Help! Rust spots on leaves

Hello! First time grower. I have a White Widow autoflower, 4 weeks into flower. Is this a calcium deficiency? Maybe lockout?
My plant is under Mars Hydro ts 300, in FFOF soil 3 gallon pot, watering at 6.8 ph with tap water. I gave 1 tbsp of Down to earth 4 - 8 - 4 week 2 of flower but that’s it. Any help on what’s causing my leaves to look like this would help. I ordered some cal mag I’m hoping that’s the issue…

Looks like classic calcium deficiency. Once your calmag arrives, use it. Be aware that the impacted leaves will not recover.

Also, try to get your pH down to 6.5 as you may be locking out other nutrients.

Best of luck.


You could have a C def going but those are old fans that are going to break down just like they are and fall off. If it’s not present on upper leaves then nothing to worry about now.


Thanks @Myfriendis410 was thinking about older leaves and when they would begin to show signs of… well, being old!

As these were only 4 weeks into flowering, thought it was a little soon. Of course, so many other factors involved. I’m heading into week 6 of flowering and have yet to see any older leaves breaking down.

Always looking to gain knowledge. :+1:t3:

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I’ve noticed not all strains grow the same way. Some strains seem to be more susceptible to issues than others. Amnesia Haze has been the one for me that always has issues regardless of environmental conditions. I also noticed that the two times I’ve grown AH for some reason the soil PH really spikes on this strain.


That’s good to know @registereduser . My next grow I really want AH. Currently blueberry. Might have to order some WW since many say it’s easier to grow and can take some abuse instead.

I would recommend Lowryder over WW. I’ve done both and the Lowryder is easy to grow very few if any issues. My last Lowryder gave 4.75 oz from one plant. Very dense and sticky buds with a really nice high. WW was ok but not as easy as the Lowryder.


Will definitely look into that strain. Have not read much about it. Thanks for the recommendation! :+1:

The ones I’ve grown were magnesium hogs. Really need to keep up with the epsom salt feedings.