Maybe the problem is that you're transferring your seedlings too soon....into a volume of mix that is too large? I would wait to transfer seedlings until they have 3 - 5 sets of true leaves. Also, you might consider starting the seeds in a screened 5-1-1 mix.

Josh

Thanks for the tips, you're probably right after transferring too soon -- I'm starting the seeds in plugs which just sit directly in a water tray. Do you think it's fine to leave them in there until they get that large? I'm then putting them in 1 gal pots, though if there that size, I might as well just stick them in their final containers.

I really don't have any advice to give, other than to put them into a transitional volume before potting them up. Can you post pics? That always helps with advice from a distance.

Josh

5.1.1 is NOT (imo) a starting NOR a newly germinated seedling medium. UNLESS as Josh said, it is screened (1/8") But when you do that it is no 5-1-1 anymore.

As far as the nutrients are concerned (N, P, K, Ca, Mg) 5-1-1 is bare. So you have to add those element ahead of time,First, soak it and then pot and plant.. So then when you transplant the nutrients are present in the medium (in desolved and available form) for the plants.

In order for an emerging seedling to grow, it has to have a good contact with the medium. When the medium is chunky, like pine bark or coarse perlite the tiny roots are in the air.

Incorrect, Seysonn, I screen my 5-1-1 over a 1/4 inch screen, so it is still fairly coarse. Roots do not require contact with the medium, as long as their is moisture/vapor present. Remember, 5-1-1 is a *starting point* not a destination. For example, I don't use peat....but I use another part of a binding ingredient.

Josh