We use a very thin layer of pine bark mulch on the seedling beds.
A thin layer helps to conserve some moisture, and we do not see so
many critters when spreading it thin. Also, it looks nicer, and cuts
down on some of the weeds.
We don't add any extra for the winter. The seedlings do very well
with this method in our locale. We seldom lose any seedlings.
Others location requirements may differ.
