Grow Mediums When to water seedlings to runoff?

[Bebop]

This is my first grow in coco. The girls are just starting day 4 and I’ve been just watering with a light nutrient solution in a small ring around the seedling; same as I would if I were starting a seed straight in soil. At what stage do I want to completely drench the coco until runoff?

I’ve done some reading, but I haven’t come across a definitive answer in relation to size, so I figured I’d attach some pics. Day 4 / 3 gallon bags.

 

[DCLXVI]

That is an interesting question. I thought always to 20% runoff to prevent salt build ups in the coco. Those seedlings can have really long tap roots already. I think it's probably safe to fertigate to runoff with less frequency and just heft the bag until it feels like it needs more or you can visibly see it drying at the top.

I know @St. Tom is a coco master and so is... ah... shoot. I forget.

 

[Mañ'O'Green]

@cf_tues Welcome to AFN Coco needs to be kept moist from before you plant to keep it alive and prevent it from becoming hydrophobic until harvest.

What you need to learn about watering will come with practice. Here are the basic rules: Never let the soil dry out. Soil and or coco can become hydrophobic if allowed to dry. This means it repels water. This in turn will create dry pockets in the soil and the roots and microbes will die there. If your soil - coco have accidentally dried out use a surfactant to help re-wet it. I like yucca powder. Don't let soil remain soggy by watering too much too often. Root rot, damping off, molds, fungus gnats and other problems start in soggy soil. When you do water water the entire pot. How to learn when to water starts before you plant the seed. Fill your container with fresh soil/coco and weigh it (heft it) this is the lightest weight and consider it a dry pot. Now slowly water until the soil/coco will no longer absorb the water and run-off begins; weigh the pot (heft it) this is the maximum water, the wettest the pot can get. The difference between wettest and driest is the maximum water weight, for ease of explanation lets just say the water weighs 20 pounds. When the pot loses 10 pounds (half of the water weight) it is time to water again. There is an art to watering. Coco can be fertigate many times a day if you want to continually present fresh balanced nutrients to the roots. Begin fertigation 2 hours after lights on and end it 2 hours before lights out.

Coco does not need to be feritgated every day when a seedling is young but when you do fertigate you need to do it to 20% run-off by the end of the day.

 

[Bob's Auto's]

 

[AMG]

I just I’m jump in here....

When - the few times I’ve been growing in coco I have saturated the medium with an EC of 0.8 and set the PH to around 5.8.

The coco will hold the moisture further down for almost a week, especially as I top-water a tiny bit every day. I would say 300ml is a good amount of feed for the girl/girls until day 7 or, then you could probably raise the amount to 500ml per watering. You don’t want to water to much in this stage as the roots are still small and you could accidentally stall them by if overdoing it.

Around day ~10 they can handle a feed until runoff but that is my plants in my grow-room under my conditions. Things as lighting and room-temperature plays a big part here and the easiest way to learn it is by trying different methods of growing in your grow-room and see where she/them responds best.
Change and try one factor a time so you know wich factor did what to your plant.

I will grow a plant in coco very soon, will probably drop a seed in a glass of water by the weekend and if you want to learn something about coco-growing you should check it out.

 

[Bebop]

Thanks everyone. Looks like I can treat them like they are in soil for the first week. I have a lot of experience watering autos from seed in large soil containers.

 

[Olderfart]

If you are new to coco, have a look at cocoforcannabis.com. The crew there know what they are doing, and provide lots of great advice specific to coco.