Abstract: A biodegradable insulating panel for a package includes a first layer of biodegradable material, a second layer of biodegradable material opposite the first layer, a moisture repellant layer, a biodegradable honeycomb core, and granulated pith. The moisture repellant layer is disposed on exterior surfaces of the first and second layers. The biodegradable honeycomb core is disposed between the first and second layers. The granulated pith is disposed within the honeycomb core to increase the resistance to heat flow of the panel. The biodegradable insulating panel has a density no greater than about 300 kg/m3. A biodegradable insulating package includes a plurality of insulating panels. The biodegradable insulating package is thermally insulating such that a temperature of an item disposed in the package increases no greater than 0.24° C./min (e.g., during ASTM D3103 test).