For seeds needing stratification: try one of the following methods:
1.) Leave the seed in the bags in which they are shipped and add just enough water so that the seed is covered by a film of water or so that the seed clumps together. For large seeds a medium such as sand should be added to improve moisture absorption. Then place the bags in the refrigerator. Check every few days to make sure the seed has not dried out. If the seed becomes moldy or starts to germinate, remove and sow in flats. After the recommended stratification period remove the seed even if it has not begun to germinate, and sow in flats. Before sowing, let the seed dry just enough that it can be separated. DO NOT let the seed dry out completely because it will die or go into very deep dormancy and may never germinate,
2.) Sow the seed in flats, moisten and place in the refrigerator for the recommended stratification period or until the seed starts to germinate,
3.) Sow the seed in flats and place outside as many days before the last frost as there are recommended for stratification. Try to keep them covered with sand to keep them from drying out, or
4.) Sow the seed in the ground before the last frost in the spring (for species that require less than 60 days stratification, or for species that require a warm stratification then cool stratification) or after the first frost in the fall (for species that require more than 60 days stratification) and let nature do the work. Keep the ground moist from about the time of the last frost until you start to see germination. Continue watering although less frequently until the seedlings have their first true leaves. If the seed does not germinate the year when sown, try not to disturb the area until next spring. Sometimes it may take a few years for difficult species to germinate, but most should take a year.