Once only commercially available, this type of popping corn is now available to the home gardener! 'Robust Pop R400MR' produces large, round popped kernels sturdy enough to hold a coating and stay in one piece, unlike the more common 'butterfly'-shaped popcorn. This is also the type of popcorn found in the popular Cracker Jacks®. Grow it in your backyard to make kettle corn, caramel corn, popcorn balls, or to top with seasonings.
• Botanical Name: Zea mays (hybrid)
• Days to Maturity: 95–100 days
• Family: Poaceae
• Native: Americas
• Hardiness: Frost-sensitive annual
• Plant Dimensions: 6'–7' tall
• Variety Information: 7"–8" ears with yellow kernels that dry to a rich orange color. It has pearl shaped kernels and about 80% of them will have a round, mushroom shape when popped. Tolerant to Grass's wilt disease.
• Type: Flint
• Attributes: Disease Resistant
• When to Sow Outside: RECOMMENDED. 1 to 2 weeks after your average last frost date, and when soil temperature is at least 60°F, ideally 65°–90°F
• When to Start Inside: Not recommended; roots sensitive to transplanting. Best results occur when seedlings are transplanted less than 2 weeks old.
• Days to Emerge: 5–10 days
• Seed Depth: 1"–1 ½"
• Seed Spacing: A group of 2 seeds every 12"
• Row Spacing: 24"–36"
• Thinning: When 4" tall, thin to 1 every 12"
• Harvesting: Let the ears dry on the stalks. The kernels are ready for harvest when they are hard and you can no longer leave a mark on them with your fingernail. Before the first fall frost, give each ear a twist until it breaks off. Peel back the husks, then hang the ears in a cool, dark, dry place for 4 to 6 weeks to cure. This is important to prevent mold and to dry to the optimal moisture percentage for popping. (In a perfect popcorn world, that would be 13½–14%.) After that, the cobs are ready for popping or storing. To strip off cured kernels, twist the cobs back and forth to loosen them (gloves are recommended).