Now that fall is upon us, you may think culturing time is over. Not at all! Some cultures like vegetables and kombucha are not quite as sensitive to lower temperatures. However, yogurt, buttermilk, sourdough, and water kefir need to be kept at least at 68ºF to culture well.There are lots of easy ways to keep cultures warm enough to continue through even the chilliest weather. For each method, test the temperature in the new culturing area to be sure it doesn't get too warm.
1. Wrap it up!
Often, when the temperature is just a tad too chilly for culturing, a towel or other thick cloth wrapped around the jar does the trick. If you're a crafty type, try making a simple sleeve to fit your culturing jars, like this one.
2. Steal some warmth.
Many electronic devices that you keep plugged in all day and night give off just a bit of warmth. Move your yogurt or water kefir onto or near the appliance, with a towel in between, just in case.
3. Use Your Pilot light.
Do you have a gas stove with a pilot light? Move your culturing jar there overnight. But make sure to leave some kind of warning sign so others in the house do not turn on the oven and bake your cultures.
4. Raise it up!
Heat rises. Take advantage of that fact by moving your culturing jar to the top of the fridge or a high shelf.
5. Seedling Mat.
If it gets too cold, try a seedling heat mat, found at local nurseries or hardware stores. These little mats raise the temperature by 10-20ºF above the room temperature. You may have to make some adjustments to get it just right for culturing, but it's a handy item for the coldest months.