Creating a mass of up to 30 yellow, sunflower-like blooms, Compass Plant is a statement to any wildflower landscape. Serving as the focal point of the garden or the backdrop, there are many ways to incorporate this native into a landscape. Compass Plant is great for attracting wildlife; the seeds are delicious to birds and the flowers are a great nectar source for insects. The low amount of maintenance this plant requires can make Compass Plant a great addition to a native landscape. May also be known as Pilot Plant.
Wisconsin Native: Yes
USDA Hardiness Zone: to zone 3
Mature Height: 3-10ft
Mature Spread: 1.5-3ft
Growth Rate: Perennial
Growth Form: Upright
Light Requirements: Full Sun
Site Requirements: Average, well-drained soil. Tolerant of temporary poor conditions
Flower: Bright yellow sunflower-like blooms
Bloom Period: July- September
Foliage: Large 12-24″ green basal leaves with white hairs, lanceolate overall
Fall Color: N/A
Urban Approved: No
Fruit Notes: Large seeds, flat and light. They are carried by wind.
Waukesha County, WI
Reaching up to 12ft tall, Compass plant creates a wonderful backdrop to any prairie or wildflower setting. Having as many as 30 blooms at once this can create quite the pop of color when paired with other native plants. Plant Silphium laciniatum in a location with full sun and mild moisture. The bright yellow sunflower-like blooms will show-off well into September until the large seeds are dispersed by wind.
Compass Plant is a tough native, as one of the taller interests in a wildflower prairie, its’ strengths don’t end there – it can also withstand occasional fires and mild flooding. The reason for such the resistance to adversity is the 15ft woody taproot. The extensive root system allows the plant above ground to be susceptible to the elements while 15ft under the surface the root system is unaffected.
Compass Plant serves as a nectar source for many butterflies and insects, both native and non-native. Birds and smaller mammals like to feast on the large seeds that are prolific in the fall. Many long-tongued bees are the top pollinators, this includes bumblebees, miner bees and the like. Other variations of “flies” will help pollinate, however not as strong as bees.
Compass Plant can be very easily grown after it is established. In a well-drained site, the maintenance is limited including only minimal care. The foliage will die-back naturally over the late-fall and winter season, so pruning is not necessary.
Compass Plant has very minimal pest problems. Generally, visitors are beneficial to native ecosystems. Powdery Mildew may arise if leaves are kept too moist during the warm humid months. This problem can be alleviated by watering from the base of the plant and not the foliage. This is not fatal problem but can be unsightly and cause the affected leaf to drop-off.
Problems that may arise, will be common with plants at such a height; falling over when planted on a slope, when in bloom and in heavy winds is a typical occurrence of the species.
Compass Plant gets its name from the orientation of the basal leaves. They are said to always be on the North-South axis, this aids the plant in avoiding the intense western or eastern sunlight.
The resin that is produced from the Compass Plant was once used as a mouth-cleansing chewing gum.
Larger natives that pair well Compass Plant are more Silphium family members, Meadow Rue (Thalictrum dasycarpum), Wild Quinine (Parthenium integrifolium), Culvers Root (Veronicastrum virginicum) and Spiderwort (Tradescantia ohiensis), to name a few. These plantings would create a large prairie and a practical privacy grove in the growing months. Smaller plants to take shape in the fore-ground are options like Wild Bergamot (Monarda fistulosa), Heath Aster (Aster ericoides), Sweet Fern (Comptonia peregrina), Goldenrod (Solidago flexicaulis, Solidago ptarmicoides, Solidago ulmnifolia), or even members of the Milkweed family (Asclepias)