By David Salman, High Country Gardens Chief Horticulturist
I've always been fascinated by seeds. The fact that plants can create little dormant pieces of themselves to broadcast out into the world to germinate is quite marvelous. Even more amazing, is how long some seeds can survive before being given the chance to sprout. There have been discoveries of bean seeds uncovered in archaeological digs that are over a thousand years old, and they were still viable and able to germinate! While not all seeds have the ability to hold a spark of life for so many centuries, it’s not uncommon for seeds that have been stored in a dry, cool place to maintain their viability for a decade.
For gardeners, seeds are an essential piece of horticulture, allowing us to propagate and grow thousands of species of ornamental and edible plants. We can do this in two basic ways:
- Germinate the seeds and transplant the seedlings into containers for future relocation into our gardens and landscapes.
- Sow and germinate seeds directly outdoors without having to cultivate and transplant seedlings.
Each method has its pros and cons. Success in either arena is mostly dependent on the skill of the gardener and favorable weather.
Sowing seeds directly into the area where you want them to grow is a fun, challenging, and cost-effective way to garden. So here are a few basics that I have used over the years to optimize the outdoor seed sowing process and some easy-to-germinate wildflower species on which to practice.
For more information about how to plant wildflowers, visit our helpful guide:
A helpful hint for seedling identification: Sow a pot full of your seed mix as a reference for future weeding. There is no point sowing a new meadow only to weed out the flower seedlings because you didn't know the difference between the weeds and your seeds.
Annual wildflowers are a great way to “color up” new gardens and landscapes. Annuals will grow and bloom in one growing season. They also leave behind ample seeds to continue to inhabit their new home year after year. It's best to sow annual flower seeds in late spring.
Plains Coreopsis (Coreopsis tinctoria) – a tough, colorful, drought-tolerant native wildflower that the bees and butterflies will love to pollinate. Color-wise, it combines best with yellow, orange, blue or purple flowers.
Scarlet Flax (Linum grandiflorum rubrum) – an Old World wildflower species, Scarlet Flax has naturalized over much of the US. The large bright red flowers are a stunning addition to your waterwise landscape.
Perennial wildflowers are the essential plant component of meadows and prairies, living for many years in the same place. Perennials grow strong, resilient root systems, dying back in winter, but returning each year as a plant that matures and grows larger each season. Sow perennial flower seeds in early spring while the nights are still frosty, or sow in fall or winter, when seeds can lay dormant until spring.
Prairie Coneflower (Ratibida pinnata) – a big colorful Midwestern wildflower that germinates readily without any pre-treatment.
Purple Prairie Clover (Dalea purpurea) – a member of the legume family, native Purple Prairie clover is not only a beautiful flower that attracts a wide variety of pollinators, but it takes nitrogen from the air and fixes it into the soil to help feed the soil and fertilize the plants. If sowing Dalea in the spring or summer, you’ll first need to cold stratify* the seed to simulate a period of winter dormancy. Take the Dalea seed and mix it into a ziplock baggie with 4 times the volume of slightly damp sand. Stick the bag in the ‘frig for 6 weeks (write the removal date on the baggie). After 6 weeks of sitting in the damp cold of the refrigerator, it is ready to sow.
Wildflower seed mixes typically include a mix of both annual and perennial wildflowers. A mix allows you to enjoy various colors as flowers bloom over the season. This way you can see bright colors in the first season, and have wildflowers that get better every year with perennial wildflowers. Over time, your meadow will mature, attracting pollinators and wildlife.