I notice when people start seeds inside, " under the lights" the soil in the cell packs aren't 3 or 4 inches deep, like it needs to be in the milk jug or liter soda bottles, which leads me to ask the question could one use those black cell packs inside the WS containers? It would help you to prevent HOS because you are only have so much space for the seeds? Hope this makes sense. Would you need drainage holes in those cell packs if you have drainage holes in the bottom of milk jugs/liters? It looks like you would need a drainage hole in bottom of cell pack too.

Pippi, the problem I've run into with smaller celled containers is drying out so quickly. One of the things I love so much about wintersowing is the ease and lack of babying. I typically don't even have to start watering them till late April or May. I used peat pots for Poppies and Larkspur once, and they required a lot more attention. So, I think it will work, just requires a lot more attention.

Me, too. In my first year WSing I tried some shallow deli containers, peat pots, and paper pots, and none of them worked well. They just dry out too fast.

Pippi, the biggest difference in outside and inside conditions, is that outside the sun and wind dry the soil much faster than happens in controlled temps, air flow, and no sun in the house. Those cell packs only hold a few tablespoons of soil and that small volume can dry quickly.

Shallow containers work fine in the house. Most of the time my trays inside are only about an inch deep.

Karen

For perennials and alpines I use peat pots inside a large Rubbermaid bin.
But I keep about an inch of water in the bottom of the bin and keep the cover over, with a space for air to get into the bin.