Rush lights were commonly used back in the middle ages. It was a cheap way to produce light from easy to find materials. The light is produced from burning the plant, Juncus effusus, after the pith has been dried and soaked in cooking fat or fish oil. These rushes are still commonly found in wetlands around Missouri and are a favorite landscaping plant today, found in the gardens of many native plant enthusiasts.
The soft rush, Juncus effusus, is an excellent native plant, great for use in rain gardens. I have a big patch of it at the outlet of my roof gutter and it does the job of soaking up the rainwater where it used to flood my yard. Soft rush likes to grow in wet sun and is good for erosion control. The stems stand up about 2ft high and stay green through most of the winter. In spring, new shoots will sprout from the base, so many gardeners cut down the old shoots to give the new shoots space but in nature they just grow up through. The resulting thick patch of vegetation provides shelter for many creatures.
To make the rush light, I find a few stalks of soft rush and clip them off at the base. I need the inner pith so I peel away the outside green layer and try not to break the spongy pith inside. Slitting the stalk lengthwise with my nail is easy but scraping the pith out in one piece takes a few tries. The pith is laid out to dry for a few days and then after breakfast I throw it in the dirty bacon pan to soak up the fat. The greasy mess is left to dry for a few more days, I try to lay the piths straight because they have curled in the grease. On the day of testing my newly made rush lights I take the fat-soaked piths out to the BBQ grill for safety. It is easy to light one end with a lighter. I try to pick one up but they are still flexible and droop causing me to toss it back on the grill. The light burns even through the tossing and emits a good amount of light. These candles are very smoky and don’t stay lit for long.
Into the 19th century, when rush lights were a regular way of lighting at night it would be placed in a dish called a cruisie. The cruisie holds the rush at an angle so it will burn consistently and catches the oil drips so they can be reused the next night.
Knowing how to make a rush light could be a good survival skill if I was lost in the wilderness and needed some light at night. I think most importantly this activity helps me to connect to the past and how the soft rush helped my ancestors to have light in the dark. Their connection and knowledge of the plants around them helped them survive and make productive use of the time after sunset.