Annual and perennial flower seeds may require stratification. Stratification occurs when seeds experience cold temperatures between 34 degrees and 41 degrees Fahrenheit for a period of three months or more. Many varieties of flower seeds require this stratification in order to germinate. Planting flower seeds in the late fall utilizes this process by allowing the seeds to overwinter in the soil. According to the North Dakota Extension Service, flowers such as poppy are placed in the ground in late September to early October for the advantage of natural stratification.
Prepare the fall planting flowerbed by cultivating the soil using either a mechanical rototiller or digging the flowerbed with the shovel. The planting location must be conducive to the flower species. In other words, if the flowers require a well drained soil with exposure to full sunlight, the planting location must deliver these requirements.
Layer up to 6 bushels of organic material per 100 square feet of soil, if the soil is of a heavy clay type. Work the material into the soil as deep as possible, 6 inches to 8 inches in depth with the shovel or rototiller.
Smooth the flowerbed with the garden rake. Remove all rocks and any errant roots that have emerged from cultivation.
Make furrows with the handle of the garden rake. The furrows should be from ¾ of an inch to 1 inch deep. Distance between the furrows can range from 12 inches to 24 inches, depending on the flower variety.
Plant the seeds in the soil furrows. Distance the seeds according to the species of flowers. Most flower seeds will do well with a 2-inch to 3-inch seed spacing.
Cover the seeds with soil to equal the depth of the furrow.
Identify the rows of fall planted flower seeds with a row marker. Write on the row marker with the black ink pen the type of flower seed planted.