Seedlings always getting burnt

Hey Guys,

I've noticed my last few seedlings have always had brown burned tips by the start of week 2
I tried different things and im left with only nute burn that it could be.
Things i tried -
1. Scrapping my entire grow box and growing in my big open cupboard - temps are now at 78.8 F
2. Adding a proper fan to move air around
3. Growing a plant out in dirt just to test - this worked and no burning
4. Adjusting PH to between around 6.5 or 6.3 cant remember exactly but it was well under 7

I use promix 50-50 which claims to be ph balanced and im 100% sure this is burning my seedlings at this point.
So today i flushed it with about 20 - 25 L water (its in an 11litre pot)
The runoff eventually started coming out clear and i let it drain properly.

So should i always flush my promix before using it to grow? or is it just not suitable at all and i should get something else? Also, how long will it take to recover from the nute burn after flushing?

Also if you think im wrong about it being nute burn please enlighten me. Because this has happened to every plant ive grown in this promix and doesn't happen if i throw some perlite and dirt together and grow with that.

Regular pro-mix isn't really loaded with shit like a fox farms soil.
Pro-mix is good stuff to use really.. a lot of growers use it.
Pics help. Week 2 in the young stage you shouldn't be feeding them anything except something like Bioroots or something like it. and microbial inoculates like Mammoth P. How much nutrients did you give them?

I didnt give them any nutrients at all. just plain water.
Im not sure the promix i use is the same one you know.
Perhaps this is a knockoff produced where i am?

Here is what i got:
Promix 50/50 (Cocopeat/Perlite) Pro Mix is pH neutral and made to our highest quality standard, using first class organic raw materials.

Promix 50/50 (Cocopeat/Perlite) Pro Mix is pH neutral and made to our highest quality standard, using first class organic raw materials. It is free from viruses and soil diseases and combines the qualities of many different organic fertilisers, rock meals, vitamins, trace elements and beneficial bacteria in such quantities that optimum growth, flowering and maximum resistance to disease and fungus are guaranteed.

Probably starting them in to big of pots, so they don't dry fast enough between waterings. At least that would be my guess. I just start plants in 2-4" pots, and let them get fairly dry before rewatering.

they are autos so i was advised to use big pots - i only water once every 7 days and only if the pot is light when i lift it up.
But even if it is light - the promix is still damp inside usually.

I use pro mix hp. I tried the one with coco and it did nothing but piss me off. pissed me off in veg, pissed me off in flower, nothing was the same compared to the HP. coco has sucked for me always.
I keep a package on the shelf just for something to blame when shit goes wrong. fuckin coco. I once burned a big wad of coco, it makes good kindling.

NinjaMaster said:

and combines the qualities of many different organic fertilisers, rock meals, vitamins, trace elements and beneficial bacteria in such quantities that optimum growth, flowering

Click to expand...

My two cents. It seems from the above, that the ProMix contains some fertilizers, kinda "hot" for seedlings. I've seen many references to the seedlings being very sensitive to ferts as they are just babies and really have everything they need from the seed itself. Most recommend starting seedlings in a very small amount of fertilizer, not even compost, in the seedling stage. Then to a hotter soil after a few leaf pairs.

Another thought is you may be experiencing burn from your lights if this is an indoor grow. Last, you might just not worry about it if it's just a bit of leaf tip burning, as long as it's not too severe and the plant grows out of it after the seedling stage.

ok it is just leaf tip burning as you say Johny B.
Ive grown years before and never had these stupid issues. i think @chemphlegm is right... im gonna fucking take these 2 bags of promix and throw them into my garage for regular old potted plants in my garden. Sure they will dig it.

For my weed though. im gonna have to look at getting a new soil or soil-less mix i think...

I've used the pro mi hp since 2008, sunshine too, everything else so far just wasnt as easy and successful for my habits. I've got no issues with pro mix hp. I only add water and organic composted chicken shit all the way through for the best we ever had. I've tried many of the common fertlizers, dry and bottled, hydro and pro mix, right away I knew I was on my win the first time I tried this Organicare/Pro Mix combo.
this might not work for everyone. I have specific gardening habits. I do know the simple system is super successful because I learned it from someone and watched others learn it to=repeatable. None of us have mites, mold, plant issues,plant maturity/finishing/harvesting times, potency issues, etc....we all grow trees in five gallon buckets under 1k lights, and likely wont change it up much. That's the Michigan way ! BuuuuYaaaahhhh!

good luck

well thanks!
Should have done this initially but here's how its looking @ start week 2 ( day 8 ) right now



you can clearly see on the 2nd image the leaf tip is all uglied
But otherwise its probably doing ok right?

im super nervous cos its auto and if i mess up then im gonna get like 1 joint out of it...

both look great, relax

I recommend you biopsy that cot tip and run lab work. JK, no biggie...yet.

haha dudes
Sorry im super critical - one day when im not a noob id like to see plants that never have anything go wrong at all - 100% health from seed to harvest.

I would avoid coco, just too many problems reported. Apparently plain old peat moss with perlite is a lot more reliable. Somebody should start selling dried peat bricks like coco, so you wouldn't have to carry a big bag of moist peat. It would be like those peat pellets used for seedlings, they expand about 10 times when water is added.

Hey Guys,

So today i check on my plants and the new growth is starting to get yellow tips as well.
in only 1 night it went from green to slightly yellow - but right on the tip still.

What is this? i moved the lights up last night (CFLS) to be sure its not that
i mean is this nute burn or is it lacking nitrogen? lol no idea whats going on haha

The plant is on day 9 right now
RH is between 40 - 50
Temps are between 78.8 - 83 constantly
I have 100w CFL over it - but ive raised it to about 4" to be sure its not burning
There is also a small 12" fan in the closet set to the lowest setting.

Get ordinary seedling starter mix from nursery dept. Compost and fertilisers can be too strong in the 1st 2 weeks. You just need a 23W spiral CFL at this stage, more than that can hurt.

Thanks @ANC . ill take out my extra lights and just leave 23 on each plant.
ill go get some seedling starter mix asap.
At how many weeks should they go into soil with nutes if they are started in seedling starter mix?