I'm planting a cover crop in the next couple of days. The winter rye I'm planting is very hardy, but to help ensure a higher germination rate I'm following a process I've done a few times before. This process also works very well for lawn seed. Take a bucket and put enough sand into it that once you mix the seed and sand together everything will be covered. Then add a little humic acid (1/2 cup maybe), Azos (tablespoon) and mix that together. Then add your grass seed and mix again. Lastly pour water so that there is enough that the entire mixture is lightly wet. Put the bucket in a warm place in the house (maybe next to a heater event). 24 hours later plant/boadcast your seed into the soil.
Doing this will get you a much higher germination rate and the seed will start growing much faster. When I did this in the fall I had roots 48 hours after planting.