To get a head start on spring planting and enjoy an extra-early crop of spinach or any other cold-hardy garden goody, try this simple tip. Cover a garden bed with clear plastic right now, and this will warm up your soil faster. Go ahead and sow spinach seed into the bed first chance you get, and your spinach will be ready to harvest a couple weeks sooner than without the plastic. It’s that easy!
source: mother earth news (www.motherearthnews.com)