Worm Bin Thermometer — Know Your Bin's Temperature at All TimesTemperature is one of the most important variables in a healthy worm bin. Too cold and your worms slow down significantly. Too hot and you risk a die-off. The Urban Worm Thermometer gives you an accurate, at-a-glance read so you're never guessing.Features Stainless steel probe penetrates up to 5 inches into soil or bedding for an accurate core reading — not just surface temperature Color-coded dial with green, yellow, and red zones — instantly shows whether your bin is in the optimal range for worms and soil microbes Works equally well in garden beds, raised beds, and compost piles No batteries required Optimal Worm Bin Temperature Ranges Red Wigglers: 55°F–77°F optimal, tolerant to 40°F–90°F European Nightcrawlers: 70°F–80°F optimal, tolerant to 45°F–90°F A simple tool that pays for itself the first time it saves your colony from a heat spike. Available as a single or a money-saving 2-pack.Works great inside an Urban Worm Bag Version 2. Browse more worm bin supplies.