One of the problems with native seed is getting it to germinate. Native seed germination is tricky, not only in the seed lab but also in the field. Even though the seed analyst has the AOSA Rules for Testing Seed as guidelines for germinating native species, there is not a complete listing of all native species nor do they take into account the various ecotypes found in nature.

To compound the problems of native seed germination, most of these species display dormancy. Dormancy has to be overcome before germination can occur. This is true whether you're germinating the seed in the laboratory or in the field.

Species Requiring a Chilling Period to Break Dormancy

Commonly, native species require a period of cool, moist stratification to overcome dormancy problems. Seed analysts refer to this as a "pre-chilling" period. This simulates the conditions that seed will find in the fall and early spring. Pre-chilling is done in the lab by placing the seeds on moistened germination blotters at a temperature between 33 and 40 degrees F for the required period of time (this varies with the species).

When pre-treating the seed with cool, moist stratification for planting in the field, the seed is mixed with slightly damp, clean sand or sawdust and then placed in a refrigerator in the temperature range suggested above. Stratification will increase native seed germination in the field of many native species but isn't necessary for all species.

Fall planting will achieve the same effect and is generally considered more practical when planting seeds in the field. The dormancy will will be broken naturally over the winter in the soil with little effort and cost.

If you have cool, moist stratified seed over the winter to plant in the spring, it is best to water the field for one or two months after planting to achieve the maximum germination of your native seed. Although the seed has been conditioned to germinate with the use of stratification, native species will revert back to the dormant state if they don't receive rain or moisture after planting.

Other Native Seed Dormancy Problems

Native seed germination dormancy problems are not solely a matter of pre-chilling requirements. Some species display hard-seededness and their seedcoats need to be scarified to allow for water uptake so that germination can proceed.

This can be accomplished in the field with fall planting as the freezing and thawing of late fall through spring will naturally break this type of dormancy in a percentage of the seeds. To gain a full stand from hard seeded species you may have to wait until the second or third year to see the final results.

Germination of many native species is dependent on light. Without light, they go dormant and will not germinate. Planting depths should be shallow. This means that irrigation or rainfall is critical to the successful native seed germination of these species.

Many native prairie grasses and wild flowers do not benefit from the moist stratification described above. These can be planted in the spring and early summer with good resulting stands. Watering will greatly increase the germination of these and result in better stands.

When to Plant Native Species

Native seed germination is dependent upon the species of seed and the time of the year that they are planted. Here are some general guidelines to increase germination success:

• Most wild flower species will benefit from being seeded in the fall. They can be planted directly into the soil or into pots or flats that are allowed to go through the winter in a moist condition at cool temperatures.
• Cool season grasses and flowers do best when planted in early spring when temperatures are cooler.
• Wetland species, like sedges, do best when planted in the fall, but can be planted in the very early spring also.
• Warm season grasses and wild flower species do best when planted in late spring and early summer after the soil temperatures have warmed up.
• If you are planting a mixture of native grasses and wildflowers together, it is best to plant in the fall or early spring.
• Always prepare the soil properly and rid it of weed problems before planting.

If you have any questions about native seed germination and establishing your prairie grasses and wild flowers, feel free to call us at J & T Green.