Have brown areas and spots on leaves

From a fellow grower: I’m past the seedling stage, but now I have issues with browning areas and spots on leaves. I’m wondering if it’s septoria, nutrient burn, too much sun, or a combination of both. I recently transplanted from solo cups to 5 gallon air pots. I’m using an off brand organic potting soil amended with worm castings and 4-4-4 Doctor Earth at 2/3 of the recommended amount (1/3 cup per 5 gallons). I sprayed neem oil on them once a week for the last two weeks as well. I plan on keeping it up as well as rotating with BT once they get a bit bigger.

They are in sun for about 6 hours of morning sun before shade for the rest of the day. I’m in the very eastern portion of San Diego (more drastic temp changes out east) at 2000 feet elevation. It’s been in the 70s and hit 81 the last two days. It gets down to the high 50s at night. I’ve been bringing them in if the temp is supposed to be lower than 56 at night.

I’m thinking too much direct sunlight right now, too quickly, but I’m not sure. I was periodically putting the seedlings in the sun for short periods of time, then inside behind a sliding glass door window, and indoors at night.




Some of that looks like pest damage. Overall they look pretty good.
I would ditch the neem oil and use Jacks Dead Bug instead. Neem can suffocate the leaves as well as the bugs. Cannabis likes lots of light so I would try to get them used to full sun all day.
I grew up in Lemon Grove and moved to Missouri back in the 80s. Your weather should be great for cannabis. I encourage you to join the forum and let the community help out. Its a great place to build your knowledge and skills.


Looks like slug/snail trails. The white dots look like flea beetles or some or kind of grazing pest. I just started using these and both work great. I’ve been using Captain Jacks Dead Bug, but I think they develop a defensive tolerance to it…


If these plants are outside put some mulch say an inch or so on top, it will help keep them from drying out. I see some type of pest damage, looks like possibly spider mites.

How many hrs of light a day total are these plants receiving?

I’m trying the Arber now, but so far it seems ineffective against spider mites in a greenhouse setting. So I’m stepping up to the fatty acid x oil base.

Do you have a tds meter?

@Borderryan22 how much Arber are u using of each? I’m using one tablespoon of each per gallon but it doesn’t seem to slow my mites. It does seem to have a slight photo toxic effect to a few leaves but very minor.

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I haven’t had mites, but may garden had, HAD, aphids pretty bad, and flea beetles have been munching away on the lower leaves of everything. I use all pest products that comes in concentrate form at 1.5x strength. So for the insecticide, I used 3 tablespoons per gallon.

I used the fungicide at recommended strength. I was using water and peroxide, but my tomatoes/squash/watermelon all got some pretty vicious brown spots.

I’ve only had the Arbor for a week. So far, I’m having better luck on the bugs and the WPM. I’ll rotate with the Captain Jack’s every couple of weeks, though, so they don’t get used to the Arbor.


Any oil based product seems to eliminate pm. We used one called instant mite killer invented by the University of Washington last year and for the first year ever had zero PM and alot less grey mold. The problem is it’s expensive. It’s nothing but soybean oil and alcohol mixed.