If you have ever bought a beautiful sourdough loaf and watched it turn soft, sticky, or moldy faster than you expected, Costa Rica's humidity is probably part of the story. Bread behaves differently here than in dry climates — and sourdough, with no commercial preservatives, follows the rules of your kitchen even more closely. For the first day or two, many loaves are best at room temperature. Keep the bread cut-side down on a board, or inside a paper bag with the cut end protected. Avoid sealing fresh bread in plastic right away: trapped moisture softens the crust and can encourage mold in humid weeks. Once you slice into a loaf, the clock speeds up. Exposed crumb pulls in moisture from the air. In Puriscal, especially during rainy season, we tell customers to plan on eating sliced bread within about 48 hours unless you change storage strategy. If you won't finish it, slice and freeze what you won't use in the next day or two. The freezer is your friend. Sourdough freezes well because the structure holds up better than many soft commercial breads. Wrap cooled slices or half-loaves tightly (freezer bag, then optional foil), label the date, and thaw at room temperature or toast directly from frozen. A quick oven finish — 8–12 minutes at moderate heat — restores crunch better than a microwave. The fridge is a middle option, not a magic fix. Refrigeration slows mold but also speeds staling (firm, dry texture). If you refrigerate, use a bread box or bag and expect to toast before serving. For many households, freeze + toast beats fridge storage in Costa Rica. Signs your storage plan needs adjusting: mold spots (discard the loaf — don't trim and eat), gummy crust, or sour smell beyond normal fermentation character. When in doubt after a humid week, shorter storage windows and freezing earlier save money and disappointment. At Kat's Lil Kitchen we bake for pickup so you can plan around your week: buy what you'll eat soon, freeze the rest, and treat humidity as part of the recipe — not a surprise guest.