Propagation: Best mix for propagation?, 0 by dividedsky

dividedsky wrote:
I was considering using fish emulsion, so I'm glad to hear that you use it indoors and it doesn't bother you. Thanks for the tip! Unfortunately, I won't have compost available, so the tea is out.

I'm not sure how to compare the coir with the peat-based mix. You probably know that the peat itself dries out (if you don't keep it moist enough) and then repels water. Coir just remains fluffy, and if it dries out, you can water it again and it's fine. Some people say that the coir retains moisture longer. I don't know that that's true. I still had to water my seedlings just like I normally would. And I don't know that you'd want that. You want the water to either be used by the plant or drain out, not sit there. Overall, there never seemed to be too much water or too little.

I've had some (but not much) success with seed starting with peat mixes, so again, it's difficult for me to compare. I'm sure it was user error on my part, but I found the coir to be practically fool-proof.

As for the paper pots, I started out thinking that I would need to use several sheets of newspaper to avoid the whole thing falling apart. It's only paper, right? But that ended up being too thick to fold after you roll them up. Two sheets or even one is sufficient. They're somewhat delicate when wet. But when I hardened off the seedlings, I made sure not to water them close to the time I'd be transplanting them. And they went into the ground just fine without falling apart. Just like you, I was amazed that they were able to hold up like that. (I've been using newspaper under my mulch, too, and you wouldn't believe how well it keeps the weeds back. It's a lifesaver!)

One thing I did notice with the paper pots is that I need to consider how long the seedlings will be in them and how vigorous the roots might become. When it came time to transplant, many of the tomato roots and some others had escaped the paper pots and tangled with each other in the bottom of the tray. And no matter how tall I made the nasturtium pots, their roots poked out the bottom as well. I might do the tomatoes in plastic pots this year to avoid that.

Trying coir as an additive sounds like a good idea if you're already having success with the peat mixes. I wish I could better answer your question on how they compare. Maybe you could do an experiment: a few straight coir pots that you could compare with your peat mix. I'd be interested in hearing what you find.

This one shows the coir close up. The lighter material is starting to dry out, and the darker material is saturated. So as it gets lighter, you can kind of use that as a guide on when to water.