Jerusalem artichoke tuber starch molds for custom herb pots in keyhole garden compost access paths

To create biodegradable herb pots from Jerusalem artichoke starch for placement in the access paths of a keyhole garden, begin by extracting the starch from the tubers. Harvest and thoroughly wash the tubers, then peel them to minimize impurities in the final product. Finely grate the peeled tubers or process them into a pulp using a food processor. Submerge this pulp in a generous amount of cold water and agitate vigorously to release the starch granules. Strain the mixture through several layers of cheesecloth or a very fine sieve, collecting the milky, starch-filled water in a large bowl. Discard the fibrous pulp into your keyhole garden's central compost basket. Allow the starchy water to sit undisturbed for several hours until a thick, white layer of starch settles at the bottom. Carefully decant the clearer water from the top, then rinse the starch by adding fresh water, stirring, and letting it settle again. Repeat this rinsing process two to three times for a purer starch. Once settled a final time, pour off as much water as possible and spread the resulting paste thinly on a tray to air dry completely into a fine, crumbly powder.

To form the moldable bioplastic, combine one part of your dried Jerusalem artichoke starch powder with four parts cold water in a saucepan, whisking to create a smooth, lump-free slurry. To this mixture, add approximately one teaspoon of vegetable glycerin and one teaspoon of white vinegar for every cup of water used. The glycerin acts as a plasticizer, making the final pot less brittle, while the vinegar helps in the gelatinization process. Heat the mixture over low to medium heat, stirring continuously with a spatula. The slurry will begin to thicken and turn translucent. Continue stirring until it forms a thick, cohesive, gel-like mass that pulls away from the sides of the pan. Do not allow it to boil.

Remove the hot starch gel from the heat and allow it to cool just enough to be handled safely. To form the custom herb pots, use a two-part mold, such as two nested small bowls or cups, lightly greased with vegetable oil. Press a portion of the warm starch mixture into the larger mold, ensuring an even thickness of about one-quarter inch along the bottom and sides. Then, press the smaller, greased mold into the center to create the pot's interior cavity. While the material is still pliable, use a dowel or skewer to poke several drainage holes through the bottom of the pot, a critical step for herb health