Consider these important factors before popping seeds into the soil:
1) Soil temperature: Most seeds aren’t going to be thrilled if their future home is below 50 degrees. Who’s to blame ‘em? Brrrr. Get yourself a soil thermometer and find out if you’re in that temperature ballpark before direct sowing most things. The exceptions are poppies, larkspur, sweet peas and calendula which are more-cold hardy than their flower friends. Kale, radish and arugula are the cool guys of vegetable town.
2) Soil Moisture: Take a handful of soil about 6″ deep and squeeze it. If it forms a wet, slippery ball and excess water oozes out, the soil is still too wet to work. If it forms a weak ball that breaks apart easily, you’re ready to go!
3) Ground cover: If your soil still has cover crop, grass, weeds, or other active plant life growing it, hold up! Your precious seed babies can’t compete for light and nutrients with plants that have an unfair head start. There are also likely a bunch of little munchers (Slugs! Ahh!!) hiding out in that matter. Pull the material out or chop it up and allow time for it to decompose. Large chunks of dead plant debris will also bind up nitrogen in the soil. Bacteria will use it to grow, multiply and further break down the plant matter.
If you want to expedite warming and decomposition, you could try tarping, building raised beds or double digging. Tillage also helps speed things up by breaking down plant tissue and oxygenating the soil. However it comes with a host of drawbacks for soil heath, so use judiciously! We use a few silage tarps ourselves to keep the soil a little drier and warmed up for early spring crops. Once we’re out of March, we prefer to keep our plastic use to a minimum and let our sheep eat down cover crop, before doing some light bed prep with the ol’ tractor.