I have started prairie seeds for years. This year, I thought I did everything right...howEVer, my liatris, coreopsis and others have not germinated. I cannot figure this out. I stratified 90 days at ~ 38F in Hoffmans (not too moist), good seed to soil contact, not too deep. Temp in basement ~50F (I thought maybe a bit cool, but figured they would come on..also under 12 hr. light.) These seeds were gathered after the drought last Summer. But these are different seeds from different areas. I gathered some over a ~month period. Moisture seems ok. No sign of rot. I have not given up and have put heat to them (68-70) hoping this will wake them up. ANY comments will be appreciated.
Growing perennial native plants from seed can be challenging. Most species exhibit some degree of seed dormancy, an innate mechanism that prevent seeds germinating too quickly, or all at once. Seed dormancy has evolved to promote germination at the optimum time, usually in spring when soil moisture levels are high. A few simple techniques can be applied to overcome seed dormancy and ensure reasonable levels of germination.
Stratification involves exposing seeds to a cold and damp period prior to planting. Most native plants do this naturally by seeding out in late summer or fall. Their seeds lie cold and damp on the soil surface for at least one winter before germinating. Stratification mimics this process. Natural inhibitors are leached out of the seeds or broken down during stratification. Place seeds in a clean bag or container with a little moisture, enough to make them damp, but not soggy. Place them in the fridge for one to three weeks, then plant immediately. Stratification dramatically improves germination in most native grasses and wildflowers. Many native shrubs and some trees need longer periods of stratification, up to two years.
Scarification is the intentional damaging or removal of the seed coat. Seeds of legumes and some other plants have tough, impervious (to water) seed coats that keep the seed dormant until at least a part of the coat has been removed. In nature this often was accomplished by the seeds passing through the digestive system of an animal. Seeds can be scarified by rubbing them between two layers of sandpaper. Or they can be immersed in sulphuric acid for a few minutes. Large seeds such as Indian breadroot can be nicked with a file. Legumes respond extremely well to scarification, and will germinate readily when planted immediately afterwards. Scarification should not be applied until the seeds are about to be sown.