Preserving the wood used to enclose raised garden beds is a conundrum. Popular wood preservatives contain toxic heavy metals that leach into the soil of a vegetable garden, potentially contaminating the soil and any food growing there. But because garden boxes are exposed to the weather and remain perpetually damp, some kind of preservative is necessary. Without a wood preservative, these garden beds need to be rebuilt with new wood every three or four years.
This nontoxic, beeswax-based wood preservative will extend the life of wooden garden beds without contaminating your soil. It forms a barrier that prevents rot-causing moisture from seeping into the wood. While it won’t make your garden beds last forever, it will certainly extend their lifespan. This recipe can be doubled to cover larger garden projects.
This recipe is a messy one. Spread newspaper over your work area before you begin. You can use activated charcoal, but you can also use charcoal you saved from the campfire or woodstove. It can be messy pulverizing charcoal, though, so plan to do this part outdoors. To pulverize the charcoal, put it in a bag to contain it and then pound it to a powder with a mallet or vegetable pounder. Sift the charcoal and use the fine powder in this recipe. Conserve the large pieces for another purpose.
Yield: 1 (10-ounce) jar
Ingredients
- 1/4 cup beeswax
- 1 cup walnut oil
- 2 tablespoons finely ground wood charcoal
Directions
- Create a double boiler using a glass measuring cup. Place the beeswax and walnut oil in the cup. Melt them together over medium heat.
- Once the beeswax is fully melted, carefully stir in the charcoal. Continue stirring until the mixture is of a smooth consistency and there are no large globs of charcoal.
- Store in a wide-mouth pint jar with a tight-fitting lid.
To use
- Apply the paste mixture with a cloth or steel wool to all sides of new boards before you build your raised beds. Allow this to dry fully.
- Reapply in 24 hours.
Beeswax Workshop by Chris Dalziel Lewis (Ulysses Press, 2016) transforms one of your hive’s most versatile products into non-toxic and useful household products.
2 Comments
Thank you for this great info. It’s something I’ve worried about for a long time now. But approximately how much wood (4 X 4) will one jar treat? One raised bed as shown in the photo?
Great idea. I may try this on my bee hives.
I must ask, though. What is the charcoal for? I understand that the beeswax is a sealant, but, I can’t figure out, what the charcoal does, other than colors the coating. Thanks!