The Master Gardener volunteers for the project were Howard Craven, Ralph Eddy, Elaine Levine, Karla Meadows, Jeanne and Art Reed, my wife Roxanne Beverstein and myself. We first tilled horse manure into a five foot wide strip down the center of our 50 x 30 foot plot. Then we laid in a length of soaker hose. Finally we covered this with a 6 foot wide strip of black plastic mulch to keep down the weeds and provide warmth. The color of the plastic is a tradeoff.
Clear plastic allows more sun into the soil for warmth, but black shades out the weeds.
The remainder of our plot was mulched with tree trimmings. We had few weeds. We planted the seeds on April 22 after the soil had reached an average temperature of 60 degrees. We made slits in the black plastic near opposite edges, and planted two sets of three seeds for each variety. We had such a cool summer this year that many varieties germinated slowly.