The blue-flowered perennial cornflower is at its best in a woodland garden where it may spread freely. If the site is not too rich, the perennial cornflower will spread moderately via rhizomes. Its habit is also better on these sites. These prerequisites are met in the arid, stony north end of Mustila’s Pähkinärinne (Walnut slope) where countless perennial cornflowers blossom at the height of summer.
The blossoms of the perennial cornflower resemble enlarged cornflower blossoms. Their vivid blue hue may tempt the gardener to plant it in a perennial border. If the soil is rich, the perennial cornflower (like many other wild perennials) usually grows too vigorously, and the stems fall down or on top of neighbouring plants. At these sites it is best to keep an eye on this plant: if support is needed, it should be given in time. The stems may be cut after blossoming to allow the plant to use its energy for growing new shoots. This will keep the stand in order and probably inhibit the growth of runners.