Pack radish, onion, jalapeño pepper, and garlic into a 32-ounce glass jar or container with an air-tight lid.
Stir together soy sauce, rice vinegar, maple syrup and hot water.
Pour soy sauce brine into container over vegetales. There should be enough brine to completely cover the vegetables, but if it's shy by a few tablespoons, top off with plain water.
Cover with lid. Keep pickled vegetables in refrigerator.