Pollinators overwinter in soil
I had someone ask me recently if it is possible to cultivate the soil in a garden bed too early in the season, in that some beneficial insects may still be overwintering in soil. Does turning the soil over by a few inches in the first week of March in Baltimore City pose a risk of exposing insects before they are ready to emerge?
The biggest concern of working the soil early is if the soil is too wet. Spading soils when excessively wet can destroy soil structure, which can take years to rebuild. As a test, pick up and squeeze a handful of soil. Bounce it on your hand. If it breaks apart easily, it's o.k. to work the soil.
As far as disrupting insects, most beneficials are not overwintering there. However, some insect pests are, and uprooting weeds and turning soil over can disrupt them, and make them available to birds for feeding. That's a win-win.
If you've not had your soil tested recently, now would be a good time to have a soil test done. Given you are gardening in Baltimore City, we suggest you choose one of the labs on our list that includes a test for lead.
See our soil page here: http://extension.umd.edu/hgic/soils/soil-testing