Compass plants’ leaves point north and south
It is hard to know where you are going if you don’t know where you are. A simple north or south can do it. Astronomer Bruce Clymer of California notes that runaway slaves used the North Star (Polaris) to show the way north to freedom. Ancient people found naturally magnetized rocks called lodestones. They suspended pieces of lodestone so they were free to turn and so became the first magnetic compasses. Indeed, the very word “lodestone” in Middle English means “course stone” or “leading stones.”
On the prairies and meadows of North America is a plant that lines its leaves up nearly perfectly north and south. Pioneers and early travelers liked to think the plant was pointing directions, but in fact the compass plant (Silphium laciniatum) faces its leaves north and south simply to minimize exposure to the glaring overhead sun.
This hardy perennial grows wild from southern Ontario south to Alabama, and west to Texas and North Dakota. Compass plant is sturdy, up to nine feet tall with sunflower-like yellow blooms up to five inches across. The flowers form loose spikes from July through September. Even the deeply lobed leaves are decorative. Butterflies are attracted to the flowers and songbirds will eat the large seeds.
One reason these plants are so hardy is that they have very deep taproots, up to 10 feet long. Long taproots are useful in bringing nutrients from lower soil levels up to the surface where they are released when the compass plant dies.
Native Americans used the fragrant, gummy resin as a bitter, refreshing chewing gum. Simply crack open a stalk and chew the resin. In traditional or herbal medicine, compass plant is used to treat rheumatism, fevers, coughs and asthma. Herbal healers use compass plant as a vermifuge that drives parasites out of the body.
Compass plant seeds can be planted in the spring or fall. If you plant the seeds in the spring, you need to break their dormancy. Do this by wrapping the compass plant seeds in wet paper towels and storing in the refrigerator for three weeks. This cold stratification mimics a winter outdoors and allows the seeds to sprout.
Plant compass plant seeds in rich, well-drained soil in full sun. Bear in mind the plant grows tall so use it as a focal point or specimen plant in a perennial border or as an informal hedge or wildflower garden.
Because it has no serious disease or insect pests, the compass plant makes a good choice for naturalizing or in informal cottage gardens, wildflower meadows and borders. It can be slow to establish itself and may not flower for a year or even two after planting.
While compass plant wont be in everyone’s garden, it will be a strong, reliable and useful plant. The bright flowers and free chewing sap are just a bonus to the phenomenon of leaves that point north and south. Plant long-blooming, exotic compass plant and you can lose yourself in the garden, but never get lost.