Direct sow after frost, or start indoors 2-3 weeks earlier. Transplant in hills spaced 6' apart, 3 plants per hill, or in rows 36" apart. Plants can grow 6' or more, so give plenty of space to take over. Mulch early to help suppress weeds. Butternut squash is easy to grow. Keep watered for the first couple weeks, and then--in most years--you can forget about them until October. Just don't get caught off guard by an early frost: once nipped, the fruits develop soft spots and quickly go bad in storage. Harvest when squash are buff-colored with no trace of green. Cure in a dry, warm place for a week or so, then store in a cool, dry, dark place.