Sowing wildflower seeds without care and planning usually produces unsatisfactory results. Here are some important factors to consider: (1) Does the site support plants now? If you have a site where nothing, including weeds, is growing, that site is unlikely to support wildflowers. (2) Will there be adequate moisture during germination and establishment? Can you supply supplemental water, if necessary? (3) What weed seeds are likely to be present in the soil? Will weeds spread to your site from adjacent areas? Assessment of these factors will enable you to make a realistic choice of a site where wildflowers will prosper and to decide what action will be necessary to ensure your success.
When to Plant
The best time to plant in your area depends on the climate and rainfall patterns as well as the species you are planting. In cool climates, plant in spring, early summer or late fall. Fall plantings should be late enough so that seeds do not germinate until spring. Late fall plantings are advantageous when supplemental irrigation cannot be provided and adequate rainfall is anticipated in the spring.
In mild climates, plant during the cooler months of the year, fall through spring, for best results. Fall plantings done prior to periods of rainfall will insure an early display of flowers the following spring.
Proper site preparation is important for prompt germination of seed and healthy growth of seedlings. Best results will be obtained by planting on cleared ground. Remove existing vegetation to avoid competition from other plants. Loosen soil by scraping or tilling. Tilling should be utilized only when soil is very compacted and further weed control measures can be taken.
On small areas, broadcast seeds evenly either by hand or by use of a drop or cyclone spreader. It is helpful to mix a carrier such as clean, dry sand with the seed; sand adds volume and aids in even distribution. We recommend using a ratio of 1 or 2 parts sand to 1 part seed. Rake in lightly, covering seeds to a maximum depth of 2-3 times their thickness.
All seeds, including wildflowers, need ample moisture to germinate and to develop into healthy seedlings. Best results will be obtained by soaking the planted areas thoroughly and maintaining consistent moisture for 4-6 weeks - then gradually reducing waterings. In non-irrigated situations, plant in the spring or before periods of anticipated rainfall. After seedlings are established, watering may be reduced depending on the climate and rainfall. If weeds are present, remember that they benefit from moisture as much as the wildflowers and may dominate overwatered areas.