Silphium laciniatum, commonly called the Compass Plant or Prairie Blazing Star, is one of the tallest flowers in central North America’s vast prairies. Mature plants can reach 12′ in height with deep taproots up to 14 feet long!
Plant it where there will be competition with other tall flowers and total sun exposure from all directions for maximum impact. It works particularly well in native wildflower gardens or meadows, while traditional flower beds will benefit greatly from having it as part of their aesthetic.
Native Range
The compass plant’s tall sunflower-like blooms make an eye-catching statement in any landscape. It is native to central North America from Ontario in Canada, west of New Mexico. Also known as silphium laciniatum, the compass plant is an iconic prairie flower that looks beautiful as part of a micro-prairie garden or wildflower meadow. Given full sun with moist to dry soil conditions, it’s straightforward to maintain.
These flowers attract pollinators such as bumblebees, making a beautiful way to bring nature into your garden. Goldfinches often perch atop solid stems, looking for insects or seeds to feed on.
The compass plant features an enormous taproot that can reach 14′ deep into the soil. It is incredibly hardy, surviving frost, severe winter conditions, and drought. Once established, its drought tolerance increases substantially, although slightly moist to dry soil conditions are preferred for optimal performance.
The Compass Plant makes a striking contrast when combined with other prairie flowers like Maximillian Sunflowers, Late Bonesets, Spotted Beebalms, and Rattlesnake Masters, as well as Little and Big Bluestem grasses, growing well in mixed meadows as well as traditional flower beds as long as there is competition and total sun exposure. It makes an attractive focal plant planted within meadow settings or near its edge for maximum visual impact!
Blooming Season
Silphium laciniatum produces an eye-catching display of yellow sunflower-like blooms from July through September, creating an incredible sight! The flower heads feature ray and disk flowers reminiscent of other sunflower family members. Furthermore, its leaves are distinctive: heavily cleft with deep divisions featuring secondary divisions in some places – something Native Americans often used as an indicator when traveling across Great Plains terrain.
This perennial is ideal for landscapes containing open grassland, prairie, or wildflower meadow elements. Additionally, it can be an eye-catching focal point in traditional flower gardens; just be sure to give it ample sunlight; otherwise, it will become overshadowed. Furthermore, its versatility extends well when combined into naturalistic planting designs alongside tall plants such as grasses or wildflowers for maximum impact!
Compass Plants are easy-care plants, requiring little in the way of watering or fertilizer once established. While tolerant of moderately dry sites, loamy-sandy soil tends to work best. A light mulch of compost or shredded bark will help retain moisture while decreasing weeds.
This plant can easily be propagated via seed collection in late August or early September. To save seeds, gently peel off their seed coat with your fingers or knife before storing them in a relaxed, dry environment for one week before stratifying.
Cultivation
Silphium laciniatum, commonly known as the Compass Plant, is one of the tallest flowers ever to grace prairie landscapes – reaching heights up to 12′ in mature specimens! Additionally, its taproot has been reported as being up to 14′ deep!
Plantain grassland ecosystems should be encouraged in naturalized areas or flower gardens with natural conditions. Due to its height, planting alongside other plants could help it withstand high winds without leaning towards the sun too heavily.
Compass plant seeds can be cold-stratified in the refrigerator for easy perennial growth or winter sown as soon as they’re ripe, filling a small pot or container with soil before scattering the seeds over the top and gently pressing down on each one. Hence, it covers but doesn’t burrow under. Place this container somewhere with morning sun and afternoon shade exposure and use misting or spray bottle moisture management to keep its soil hydrated.
Compass plant thrives in various soil conditions, from loam or sandy loam soils, through dry sites with some moisture present, to sunny locations with late boneset, spotted beebalm, and prairie blazing star. It thrives alongside other flowering perennials and grasses – sunflower, late boneset, spotted beebalm, and prairie blazing star all thrive together well!
Wildlife Attraction
The Compass Plant stands out against the sky with its sunflower-like blooms, making them easy to spot from a distance on the High Line. Pollinators such as bees and wasps swarm around its tall stalks while its seed pods become popular food sources for songbirds in the fall ripening season. It is a perfect wildflower for prairie and habitat gardens due to its deep taproot that makes it drought-tolerant once established!
Silphium laciniatum, a native perennial of the central United States, is a highly durable, long-lived native perennial flowering along the Great Plains and has long stalks and deep roots, which makes it a sought-after choice for xeriscaped gardens. Pairing well with wildflowers such as Sunflower, Late Boneset, Spotted Beebalm, Prairie Blazing Star, and grasses such as Little and Big Bluestem Grass makes for a stunning display!
