Sweet corn takes between 60 and 100 days to mature but the window when ripe corn is at its prime sweet flavor doesnt last long. If the corn plant is okay it will be firm solid healthy and strong. Fresh Ear Of Corn Ready To Be Picked I Pulled Back The Shucks So You Could See The Kernels Frozen Fresh Freezing Fresh Corn Sweet Corn Its not always easy to know when to harvest corn especially if youre a beginner. When is corn ready . Ripe corn feels firm with the kernels filled out from top to bottom. Some labels also indicate the minimum corn growth stage before POST applications should be made. Approximately 20 days after that moment you can expect your corn to become ripe. Washington State for fruit vegetables pumpkins and other crops. The soil temperature should be above 60F. The tassel consists of the silk of the corn. To know when sweet corn is ready to pick do this. If you can pierce a kernel and a milky liquid comes out the corn is perfectly ripe and ready to h...