The fragrances and flavors of herbs derive from oils that slow water loss and make them hardy enough to grow inside during the winter.
Step 1: Dig them up Dig up herbs before the first frost and plant them in fresh soil, allowing for a couple of inches around the root ball.
TIP: Check for insects which, if present, can be eradicated with a soap spray.
Step 2: Choose hardy plants Choose hardy plants to bring inside. Transplant them to containers that are deep enough for roots and that have drainage holes.
Step 3: Keep them outside Keep the potted herbs outdoors -- but out of direct sunlight -- for a week. This will condition them for less sunlight and acclimate them to the containers.
Step 4: Maintain light Maintain five hours of direct sunlight daily to keep the herbs fresh. Turn them on a windowsill for even light, or expose them to fluorescent lights hung six inches above the herbs for 14 hours per day.
TIP: Don't let the leaves touch the cold window glass during winter, which could inhibit survival.
Step 5: Group herbs Group your herbs closely to create humidity. Set your pots on a layer of gravel to ensure cool moisture without waterlogging the plants. Use liquid plant food at half strength to boost their health.
TIP: Winter-kept herbs only need to be watered once or twice a week, usually in the morning. Don't let the soil dry completely.
Step 6: Harvest a little each time Harvest your herbs in small quantities, leaving at least two growth points for new shoots to encourage density. Enjoy your fresh herbs all winter long.
FACT: Archeologists have discovered evidence that as early as 50,000 BCE, humans used the leaves of plants for flavoring meats.