Sow seeds directly outside anytime March to mid-Oct (September is ideal for use as a winter cover crop). 1 oz covers approx 55 sq ft (1.5" spacing between seeds). Plant seeds ¼-½“ deep (you can drag the back of a leaf rake to cover them) or they will germinate uncovered if kept constantly moist. Rye is widely tolerant of soil type and moisture, and can germinate in soils as cold as 33°.
Rye will only produce seed heads if exposed to winter temperatures (vernalization), though it can be spring planted as a cover crop (green manure, weed supression, nutrient scavenging). Grows well along with hairy vetch, typically at 2 rye : 1 vetch ratio by weight. Rye is often killed in spring by plowing, tilling, tarping or crimping when it is at height of ~20". Rye can also be killed by mowing right as the crop begins flowering.
Rye grain is ready to harvest when stems have turned brown and seed heads begin to droop, usually mid-July through mid-August. Harvest seed heads for dried flower arrangments anytime after the seedhead is plump.
Rye is wind pollinated, so plants may cross-pollinate but this is seldom a problam for home seed savers. Clean seeds by threshing grain off stem, screening and winnowing to remove chaff and contaminants. Save seed from as many plants as possible.