Grey Tips on Seedling

[Doug Dawson]

Hi guys,
First time grower here and first time poster so please take it easy on me

I’m growing in a 3x3 tent with the plants in their final 5 gallon pots already. Have a Phlizon 2000W (430 true draw) Using 50%coco, 30% vermiculite 20% perlite mix. pHing my water around 6.2pH, temperatures sitting around 80 F and humidity solid 54%.
I haven’t given any nutrient feed to the babies yet, but I didn’t wash my medium before.

the plants have been growing well, getting good height on them. However 2 of them have been showing grey tips as of yesterday. I am wondering what may have caused this? Is it overwatering or does the medium have some sort of disbalance in it.
Thank you so much for all your help

Welcome to RIU and the hobby. A couple things, is this an auto? If not you should be starting in smaller pots and moving up as you go. If you use a large pot the roots will head down to the bottom and fill in leaving a large space in between which is not good. Now for the coco, you should water your coco to good run off before use, it's just good practice. Not all coco is created equal. The rinse should contain calmag and a small amount of nutes. I grow with the GH trio and find 1/4 what they recommend is perfect for this stage. The big key is to not over feed them, just minimal amounts. Some will argue you don't feed the seedlings for a week or 2 but I do. If you were growing in soil you would have nutes, you should have the same in coco. I cannot say it enough though, 1/4 strength so you don't hurt them. If you drop the vermiculite and just use a 70/30 coco/perlite mix you will have a good medium. The reason they say you cannot over water with coco is because in soil when you over water there is no o2 for roots. When you use coco/perlite there is always o2 available for the roots. Good luck.

 

[Doug Dawson]

I added some vermiculite to help with holding water and nutrients and the perlite for aeration. Coco itself is decent at holding on to water but not as good as vermiculite. My light is pretty strong, I wanted to make sure the plants have food readily available for them while I sleep.

If you are concerned than water twice a day, once before bed. A 5 gallon pot will take some time to dry out.

 

[BustedOvaries]

Welcome to RIU and the hobby. A couple things, is this an auto? If not you should be starting in smaller pots and moving up as you go. If you use a large pot the roots will head down to the bottom and fill in leaving a large space in between which is not good. Now for the coco, you should water your coco to good run off before use, it's just good practice. Not all coco is created equal. The rinse should contain calmag and a small amount of nutes. I grow with the GH trio and find 1/4 what they recommend is perfect for this stage. The big key is to not over feed them, just minimal amounts. Some will argue you don't feed the seedlings for a week or 2 but I do. If you were growing in soil you would have nutes, you should have the same in coco. I cannot say it enough though, 1/4 strength so you don't hurt them. If you drop the vermiculite and just use a 70/30 coco/perlite mix you will have a good medium. The reason they say you cannot over water with coco is because in soil when you over water there is no o2 for roots. When you use coco/perlite there is always o2 available for the roots. Good luck.

Thanks so much for your detailed response! The ladies are photoperiod, figured I’d start them in their final pots to avoid root damage later since I’m still an amateur. It all makes sense, I think I got a better ideas with the whole process now. Definitely will apply these things for the next grow.

 

[BustedOvaries]

Here’s an update on the baby so far. I flushed with 300 ppm pH balanced water with GH micro and bloom, looks like it helped stop the greying/dying. She put on a bit of weight since then, but showing some yellowing. I wonder if the nutrients were too much. It’s time for a feed today, going to half the nutrients again.