Eryngium yuccifolium, commonly called rattlesnake-master or button snake-root, is a native plant which occurs in rocky woods, prairies and glades and was a common plant of the tallgrass prairie. Most members of the parsley/carrot family (Apiaceae) have finely cut foliage and flowers in domed umbels. Not so with rattlesnake-master which features basal rosettes of parallel-veined, bristly-edged, sword-shaped, medium green leaves (to 3' long) resembling those of yucca (lily family) and tiny, stemless, greenish-white flowers tightly packed into globular, 1" diameter heads resembling thistles (composite family). Flower heads appear in branched clusters at the top of smooth stiff stems typically rising to 3-4' (less frequently to 5-6') tall from the centers of the rosettes. Flower heads are subtended by whitish, pointed bracts. Also can be effective in borders. Easily grown in average, dry to medium, well-drained soils in full sun. Prefers dryish, sandy soils. Rattlesnake Master plants add a unique display to flower beds with its unusual compact flower clusters and flower seed heads, and it can be a wonderful focal point. Eryngium Rattlesnake Master can be used for roadside plantings, prairie restoration, prairie landscaping, wildlife cover, and also in wildflower gardens.
The seeds have a period of dormancy. They can be planted outdoors in the fall or winter for spring germination or they can be cold stratified to simulate winter conditions and to break their dormancy at any time of the year.
- Place the seeds in a plastic bag and seal it. Store the bag in a refrigerator for 3-4 weeks.
- The seeds like moist, well-drained soil. Fill a pot with a mixture of half potting soil and half sand or vermiculite. Water the mixture so that it is moist but not wet.
- Sow the seeds on the soil and cover them with a thin layer of soil.
- Water the container and leave it to drain.
- Put the pot in a warm, sunny area.
- Water the pot regularly so that the soil is moist but not wet.
- The seedlings can be transplanted when they are a few inches tall.