Leaves turning brown on indoor grow







The reason for this is, because a newer grower will use a chemical nutrient
most of the time and listen to the directions on the box. This is a NO NO!
Depending on the age of the plant, size, strain and soil mixture you are using
also has a factor. There is no set guideline when using nutrients, but I can
give you a good example to start out with so you will not burn your plants.
It’s always good to start out light, rather than feed heavy. Remember you can
always add more later, but can not take out when you added to much. Chemical
and Organic nutrients differ. Chemical nutrients are more readily available
and can burn way easier than organics can. Organics are easier for a newer
grower to use, most of the time, and lessen your chances of burning your plants.
I recommend not using more than ½ teaspoon of chemical nutrients per gallon
of water. Unless the plants are very big 5 feet+, then it’s safe to use 1
teaspoon per gallon of water. When your plants first emerge you want to wait
at least 2 weeks before feeding your plants, unless your plants are in a soiless
mixture, like pro mix. The cotyledons (its first set of round looking leaves) are
what give the plant its food until they get the first 2 or 3 sets of leaves. If
your plants are in a soiless mixture and are over the first week of age; you can
feed a weak amount of nutrients, like ¼ teaspoon per gallon of water. Soiless
mixtures are different from soil plants and soiless plants need to be fed more
when using this mixture.

I also recommend not feeding more than 1 time a week if using ½ teaspoon per
gallon of water for chemical nutrients. You can feed every other day,( this
goes for chemical and organics) at very weak amounts, but doing this may contribute
to over watering, and for that I do not recommend feeding more than once a week.
Some people feed 2 times a week using like ¼ teaspoon per gallon of water… Use 1/4
strength for first feeding and then go up to 1/2 strength from the 2nd feeding when
using chemical nutrients. It’s very easy to overdo it. When using organics, depending
on which one you’re using, I recommend using 1 teaspoon per gallon of water. When the
plant gets bigger you can work your way up to using more nutrients when the plants
get bigger.

As for soil mixtures, there are a lot of different kinds of soil’s out there. Using a
rich soil mixture is not recommended for seedlings. Seedlings that are under 2
weeks of age you do not want to start them in rich soil, using a seed starter
mixture is one of the safer ways. Seed starter mixtures are weak in nutrients,
so it will not burn the seedlings but will provide them enough to get past seedling
stage, but the downside is you have to transplant into a better soil mixture after 2
weeks of age. If you decide to start with this mixture, do not put your seedlings
into a big pot. Start them out with using a cup or a small pot.

Nutrient Burn causes leaf tips to appear yellow or burnt. They can also be brown
and twisted and crispy looking. Depending on the severity it can show many different
symptoms and shows on lower part of the plant when its young, at older stages it
can move anywhere on the plant.

To fix the problem when you have Nutrient burn, you want to flush out the plants
with lots of water.


Soil should be flushed with lots of water, Use 3 gallons of water per one gallon of soil.
Flush very thoroughly, after plant recovers usually after a week, you can resume using
nutrients after a week or a week 1/2. When you flush your soil, you flush everything out,
a lot of nutrients go with it, including the soil nutrients.

Hydro `````````````````
Change out the reservoir, flush out any lines and clean out the entire system and
replace with plain water for the first hour, then start out with lower parts per
million (PPM)
Its good to clean out your system every 2 weeks and replace with fresh water and
nutrients. Some people change everything every week!

Ahh, nute burn! Stop this by not adding to much chemical/organic nutrients to your
water,foliar feeding. DONT feed more than 1 time a week unless using weak amount,
use 1/4 strength for first feeding and then go up to 1/2 strength from then on when
using chemical nutrients. Its very easy to overdo it. Causes leaf tips to appear
yellow or burnt. NEVER give nutrients to plants that are under 2 weeks of age, at
this age the soil nutrients are enough to suppliment them untill 2 weeks of age or
more depending on how good your soil is. Using ferts before 2 weeks will almost
likley kill your plants.

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Thank you Garrigan. Okay so now this is what I thought it was too bc honestly I did use nutes early BUT I was using around a teaspoon per gallon like you mentioned. With that said I started to flush the plants out. I used RO’ed 6.8 pH water and for at least a week and a half soaked them. The problem didn’t subside so I just assumed this wouldn’t be the issue.

So what you’re saying is I need to get rid of nutes completely and flush these girls out until I see this go away yeah? My water should be pH’ed @ 5.8 or 6.8 I’m doing so? My runoff is staying around 5.5-5.9


Depending on if you’re using soil or coco will tell you what Ph to use. If you’re in coco then 5.8 is fine, but if you’re in soil then your Ph should be between 6.3 and 6.8.


btw a teaspoon can be 5.grams or more. depending on the type that can be a crap ton of nutes

AND nutes build up in your growth medium and theres no way to know how much is in there unless u measure runoff


So to test the runoff for nutrients deficiencies I can use this TDS meter? How do I know for certain if this is a combination of issues? Do I need to flush these girls out until this stops? Still kinda waiting on the consensus.

I’m in moonshine so I assume per the post above I need to be around a 6.0 pH correct? And flush like crazy until the browning stops?


Yes, by measuring the TDS/ppms of the runoff you can help detect if you have over-nuted (or under) your plant.

I believe that you should be watering at 5.8pH because you are in a coco based soil.

Usually, when a plant has problems, it has a couple of different issues. It may have a deficiency or lockout, but its driven by a pH or soil issue, not necessarily what is available in the soil. These investigative steps help us narrow down the problem.

I would not flush until you measure the ppms, but that is my opinion. I water every other day with 1/4 nutes to significant ruoff (I put 2.5 gallons through a 10 gallon pot). For you, I would hit it with plant 5.8pH water with significant runoff for the time being until you can measure the ppms.


Roger that sixpack thank you so much. I will have this meter tomorrow and will be able to come back here for advice before I do anything more.


So should I get some Calmag while I’m out getting this meter? My girls are literally almost dead. At least 6 of them.


I personally don’t use it because my well water has plenty to begin with, but wouldn’t hurt to have on standby if you need it


Okay so here is the latest from today. I went to the store I bought my moonshine from and he specifically told me this coco based medium is specifically engineered for Cannabis. He said I shouldn’t be adding ANY nutes at all for the first month of life.

With that said I watered today pH’ed @ 6.0 to about 30% runoff. I took the runoff water and tested with a TDS meter and came up to around 1958 average. Assuming this means I’m way over the top. I’ve taken the excess water from the trays and dumped and plan on repeating this process until I see recovery signs. My runoff pH is 5.7’ish. I did purchase the Calmag but would you agree the process is to flush significantly over the next week or two?


If it looks like your plants can handle it, I would flush them now with 5.8 pH water until your ppms are 1000 or so.

I water every other day. I would hit it next with water and calmag then if you are using r/o water.


I flushed them today with 6.0. I got rid of the runoff water and plan on watering them again each day until I see runoff then discarding it. Seems like this would be faster than allowing the runoff to be absorbed through the bottom


You definitely don’t want to let it sit in the runoff. I have my fabric pots on egg crates in a shower, so I have it easy and just pour it in and let it all go down the drain.


Are you letting your pots sit in the runoff tray? If so then the plants are reabsorbing the nutes that run off and increasing your tds… is that how you are testing? I was making the same mistake. I got some of those plastic bread trays from the grocery store use and sat the plants on those and aligned my catch (runoff) tray underneath. Then when I water to runoff I either have a friend lift the plant to catch the water to measure or do it myself or take it from a clean catch tray… This will get you true readings


That’s exactly what I was doing jt. I didn’t realize I was supposed to be discarding honestly. It actually kinda clicked in my head yesterday and decided to start discarding it for faster results on the flush. Didn’t think about it feabsorbing the runoff :grimacing:


I was thinking it looks like chlorine issues. Does your tap water have chlorine? If yes, did you ever do anything to mitigate that?

I see others have you set with getting your pH & ppm’s situated. :grinning:


Well I’m sure the tap water I was using had chlorine but I switched over to RO water. I tested the ppm of the RO water and came up with 11ppm


You are watering today with 5.8pH water until you get the ppms under 1000? Once you get there with the ppms, I’d hit it once more with some water plus calmag. I haven’t needed calmag, but I think it is important to supply your plant with it if you are using RO water.

I’m not sure how difficult it is for you to remove the runoff, but I move my guys to a bath tub an water in that. I’ll water, test my runoff, let them sit and drain for a bit, then return them to the tent.


So I need to flush it over and over in a single sitting until I get to that ppm? I was under the impression I need to keep doing every day until I hit that number so it didn’t stress the plants too much. But if I can do it all in one sitting without destroying my plants I can do that.


Yes, flushing all at once is how I was taught here. In my first grow, I had a plant at 7500 ppms. I flushed what was a ridiculous amount of water to get down to 500. It’s like a Reboot for your plant soil. You are also in soilless which dries fast so I don’t think you will overwater or stress the plant.

The damaged stuff won’t heal. The key is that the new stuff is.