I leave them in the plug trays until they appear to be root bound - need watering almost daily. I let me peas go three weeks and thought they had filled the plugs (200-cell) but when I transplanted them I had to be very careful or the roots would separate from the mix.

IME, it is nearly impossible to overwater them, if you water from the bottom. I have (stupidly!) forgot about a tray of plants in a tub of water, gone back the next morning to find a soaking tray. Remove it, let it drain and it is good to go.

Mike

Thanks Mike
I think I have not been watering enough. Bottom watering sounds like a good solution. Top watering I couldn't tell what was soaking in and what was running off. And definitely leaving them to grow longer.
Kathy

What I do is, place a 1020 No Hole under my plants to catch the water. As long as I let them get dry occassionally, and then water again, it's worked for me. I started doing it this way when I had to pack water for everything.

Marla

Another way to get good roots is to use something like Tomato-tone (3-4-6 with microbes). I add a tbsp. per gallon of water and then add that gallon to another gallon of water (or so). Use it every other week. Most of the Nitrate is not water soluble but if you have enough carbon products to add, the residue is great in compost.

Mike

I just use plain water, preferably rain water. I do use Miracle Grow potting soil with the water control feature. After the plants are ready to go into large pots, gallons or more, I'll use some compost and fertilize in the water every other week.

Marla