Help! What is doing this to my vegging plant?

Strain: Jack Herer feminized
Passive Hydroponic - Perlite and Hydroton, nutrients are hand sprayed mixed with RO water few times a day
pH of mixed 3-part nutrient is between 6 - 7 and the runoff is the same, no pH pen right now, using pH paper.
5ml of Micro, Grow and Bloom per 1 L of water, I feed around 300 ml per day over a few times when under light
No EC/TDS meter right now
This is a balcony grow, decent amount of indirect light all day and a few hours of direct sunlight available
Currently supplementing the 18/6 cycle with a 50W 6500K 90+ CRI 5000 lumen LED
Ambient air over 24 hours ranges from 23° C to 27° C
Relative humidity ranges from 19% to 60% (monsoon here)
Wind speeds range from 5 - 25 Km/hr

Grow log - Jack Herer Fem balcony - #8 by JackHerer

The top of the plant looks happy but some of the lower leaves have yellowed to browned and fallen off.
But some of the lower leaves are showing this weird veining.

Some of the top leaves have developed tiny white spots so I took a microscope to it today.
But there’s so much water on the surface, I can’t see much else as it reflects the microscope’s LED back to my eye. Is this a parasite or a deficiency?

What can be done to fix this?
Will neem oil spray once a week help?

Caused by a leaf miner I think its called

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Looks like leaf miner. Google leaf minor and you will see lots of info. Search this site and find this:

Found this for you:

The most common method to rid plants of leaf miners is to spray general pesticide on the infected plants. The trick to this method of how to kill leaf miners is to spray at right time. If you spray too early or too late, the pesticide will not reach the leaf miner larva and will not kill the leaf miner flies. To effectively rid plants of leaf miners with pesticide, in the early spring, place a few infected leaves in a ziplock bag and check the bag daily. When you see small black flies in the bag (which will be the leaf miner larva becoming adults), spray the plants daily for a week. There are pesticides that are specific to killing leaf miners by actually be absorbed into the leaves of the plant. These leaf miner specific sprays can be used at any time of the year. While pesticide is the most common form of control methods for leaf miners, it is not the most effective. Naturally killing leaf miners with beneficial bugs. You can purchase wasps called Diglyphus isaea from reputable nurseries. These leaf miner natural enemies will make a meal of the leaf miners in your garden. Be aware that spraying pesticides can kill these beneficial bugs (and other less commercially available leaf miner predators you may have naturally in your garden). Another way of naturally killing leaf miners is to use neem oil. This insecticidal oil affects the leaf miner’s natural life cycle and will reduce the number of larva that become adults and thus the number of eggs that the adults will lay. While neem oil is not an immediate way how to kill leaf miners, it is a natural way to treat these pests.


first pic is a leaf miner eating the center of leaf. treat it.

second pic looks good all the way around.

You are very lucky your water is good ph. Flying blind without a PH n PPM meter set. $20 amazon or ebay. Critical

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Thank you all for the quick responses, I spent some time reading on leaf miners.
The local pesticides for it here are Cartap Hydrochloride or Triazo organophosphates and suggest 250ml/acre so they’re pretty concentrated.

I have removed the three lower leaf nodes that were bored by the miners, one of them has been bagged to observe when the larva turn to flies. The other two leaf stems were burnt over a cooking station slowly and with hatred for the leaf miners :frowning: I have readied the neem oil mixture and will apply every day for a week once I see black flies in the zip lock.

What do you guys make of the tiny white spots on the top leaves in the second photo?

@tanlover442 I use pH paper which would at least tell me if the nutrient solution was way too acidic or alkaline. I rather move to AN pH perfect nutrients than get a bunch of ph and ec pens.

The pH pens are cheap and super easy to use. Highly recommend it. The paper is very hard to see the difference between 5.5 and 6.5 for instance and these plants are a tad fussy about pH. Biggest issues I see over and over are over/under watering and ph out of whack. Good luck with your grow. Addictive hobby!! :slight_smile:

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The pen’s available locally seem pretty flimsy and have kept me from spending on them, will order a decent set soon. The white spots on the top of the leaf seems like it might be the start of leaf miners attacking it, !@#$ I hope the plant will make it to flowering :frowning:


Anyone have ideas what the white spots on the top leaves may be? Are they too young leaf miners?

Bumping in the hope someone tells me the white spots are nothing to worry about :frowning: