I have had a request for How-To "Wintersow" Instructions. This is a method using milk-jugs, which I find the easiest.
Timing: I find Mid March a good time for a couple of reasons. We typically don't get hit with extreme cold temperatures and the days are longer - works best with 12+ hour daylight
What can be wintersowed: Any perennials hardy to your zone, all seeds that require stratification (pre-chill) and also any seeds that the seed package states direct sow "x" number of weeks before last frost and/or "early spring", "as soon as the ground can be worked" or "late fall". (note: ignore the suggested number of weeks before last frost). At the end of May your ws seedlings may look small, but by mid to late June they will really bolt.
Do not wintersow: Tropicals and expensive seeds that take 12 weeks to bloom from germination. You will be disappointed.
Perks: Low maintenance. Do do not have to worry about lights, germination temperatures, damping off, hardening off and for the most part Mother Nature will also take care of moisture, but do check that they do not dry out and become parched.
PREPARING THE CONTAINER
1. Clean the milk jug (throw out the cap). I add bleach to the soapy water to disinfect.
2. Put at least 5 drain holes in the bottom of the jug. I use a 1/2" drill bit on a cordless tool
3. Slice venting holes along the neck of the jug
4. Cut the jug in half, leaving a "hinge"
See photo:
