While driving through Oklahoma, it is not uncommon to see patches of wildflowers along the highway. Wildflower gardens can be a great addition to any landscape with their vibrant colors and variety of flowers.
In some ways, wildflower gardens are more environmentally friendly than traditional gardens. Although most plants will survive for a period of time in a given environment without human intervention, wildflowers will need the right conditions to function in the manner desired. Fertilizers and other amendments may be necessary when environmental conditions are not ideal. Once established, wildflowers should grow well as they are accustomed to the soils and growing conditions of the local climate.
Late fall is ideal for planting a wildflower garden. If you are planning to plant one, it is important to understand seed dormancy. Many native species have evolved to germinate only when conditions are ideal, such as after a heavy rain or a fire. Typically, seeds need a cool, wet period to break dormancy, also known as stratification. Dormancy can be broken artificially by placing the seeds in moist growing medium in the refrigerator for about four to eight weeks.
Some seed companies sell seeds that have already gone through this process. However, others do not because untreated seeds have a longer shelf life. Here in Oklahoma, it is recommended that you plant your seeds in late fall to ensure the seeds go through natural stratification or some other dormant breaking process. In areas that receive more snow, a post-frost / snowfall planting is ideal. Another plus is that a late fall planting will not interfere with more urgent spring garden chores.
What should gardeners do to create a wildflower garden? As with any garden, the choice of site is essential. Consider factors such as sun and wind exposure, drainage, site topography, access to the site for maintenance and available irrigation. It is important to clear all vegetation from the site. This process may take some time. Non-selective post-emergence herbicides are an effective means of killing perennial weeds growing in the area and several treatments may be necessary. After plowing, the area should be left relatively calm for enough time to see new weeds growing, which then needs to be treated.
Successful sowing of seeds will lead to a complete garden with a balance of selected species throughout the space. If the space is large, separate the area into equal parts. Combine your seeds and mix well, then divide the seeds into equal parts – the same number as the garden space is divided. Then add a moistened filler, such as sawdust, compost, peat moss, sand, or rice husks, to each section of seed. Add three parts of filler material to each section of seed to create a diffusion mixture. Spread the mixture over each area and tamp the seed lightly with your feet or other tools to ensure good seed-to-soil contact without burying the seeds too deeply.
Remember that wildflower gardens are not effort to set it up and forget it. After the seeds are planted, watch for cool-season weeds. Once the garden begins to grow next spring, it will need maintenance like a normal garden, depending on the overall aesthetic and purpose of the garden.
Wildflower gardens are growing in popularity among gardeners looking for ways to improve native ecosystems in urban areas while looking to reduce the resources required to keep their gardens beautiful. This type of gardening lends itself to bringing some of Oklahoma’s natural heritage to the backyard and demonstrating the diversity of Oklahoma’s flora.
Oklahoma State University Extension offers more information on wildflower gardening.
David Hillock is a mainstream horticulturalist at Oklahoma State University Cooperative Extension.