Corn seed saving is a time-honored tradition that can help you to be self-sufficient and reduce your reliance on big agribusiness. It is also a great way to preserve heirloom corn varieties for future generations. In this guide, we will walk you through the process of harvesting corn seeds, preparing them for storage, and storing them under the right conditions.
When to Harvest Corn Seeds?
The best time to harvest corn seeds is when the ears have fully matured and dried. This typically takes place around mid-September, depending on your climate. You should wait until the husks are completely dry and feel brittle to ensure that the kernels inside have also dried out completely.
Once you’ve determined that the ear is ready, gently peel back the husks and remove the cob. Place it in a paper bag or other breathable container to allow any remaining moisture to escape before you proceed with seed saving.
Seed Preparation for Storage
Once you have your mature ears of corn, it’s time to prepare your seeds for storage. The following steps will help ensure successful germination in the future:
- Separate the kernels from the cob – use a corn sheller to remove them easily;
- Float test – drop your kernels into a container of water; any that float can be discarded as they are likely to be empty or contain insects;
- Air-dry – spread the kernels in a single layer on a screen or newspaper and allow them to dry for 3-7 days, depending on the humidity;
- Cleaning – remove any remaining chaff, dust, or debris by sifting through the seeds with your hands before packaging;
- Heating – heating the kernels to a temperature of 110-115°F before storage kills off any insects or pathogens that may be present;
- Packaging – store your cleaned and dried seeds in an airtight container such as a Mason jar or vacuum sealer bag to keep out moisture and pests;
- Storage conditions – ideal storing conditions for corn seeds are in a cool, dry place with temperatures between 40-50°F and humidity levels at or below 60%. Seeds should also be shielded from direct sunlight.
How Long Do Corn Seeds Last
Corn seeds can last for several years if stored correctly. If you take the proper precautions during seed preparation, storage and handling, corn seeds can remain viable for up to four years or longer. Some varieties may even have higher longevity depending on their genetic makeup.
The most important factor in determining how long your corn seeds will last is the temperature and humidity levels of the storage conditions. Keeping the temperature in a range between 40-60 degrees Fahrenheit (4-15 Celsius) and humidity below 50% will help ensure that your seeds retain their viability. It is also important to make sure your seed containers are airtight to keep moisture out.
The data below showcases how the rate of germination decreases as the time of seed storage increases.
- 1 year – 86%
- 2 years – 80%
- 3 years – 72%
- 4 years – 62%
- 5 years – 33%
- 6 years – 14%