Here in Missouri we have very cold winters and we must take precautions to save our beloved herbs and flowers if want to keep them around for next year. I have LOTS of outdoor herbs and plants that I take advantage of throughout the warmer season and harvest all that I hope I need to make it through the winter. I am not a huge user of fresh herbs in the kitchen. If I have them then I use them fresh, but if not, I have no problem using dried herbs that I have harvested in the past. Therefore, the need of growing herbs indoors is limited to the need I would have of them fresh or my ability of saving a plant that would otherwise die in our cold and not return the next year. Some plants are real iffy and may skim by one year but not make it the next.
The plants that are a toss-up in our weather and that I like having around are mostly Rosemary, Oregano, Sage. Some people say that if you mulch around them really well in the Fall then they will survive. I have always brought them in and this year I am leaving them out to see how they do. I plan on mulching with some straw after the leaves have all fallen and been cleaned up. I don’t worry too much about bringing annuals inside because these plants can easily be planted directly in pots. Most of the time they are at the end of their life cycle by the end of the Summer anyways and so transplanting would be unneeded.
My favorite FIVE (plus a bonus) plants to grow inside just to have them available for magickal uses are Rosemary, Sage, Oregano, Basil and Thyme. Basil is pretty simple and I plant it directly in a potting soil from seed. Keep it in a sunny window and let it dry out between watering. The other four plants seem to do the best planted in a cactus mix potting soil. They love the sandy soil and the cactus mix seems to work really well. These all need to be in a window with at least 6 hrs of light, kept at around 70 degrees and they tend to get root rot easily if over-watered. It’s best to let them dry out between watering and then water thoroughly. The Rosemary likes it even drier than the rest. I like to frequently mist the air around the plants to increase the humidity. This also will deter red spider mites on indoor rosemary plants which tend to be a real problem.
If you are bringing these plants inside from a summer outdoors then you will need to do so slowly. Pot them in the mixes described above and then place them in a semi shaded area outside so that they can get use to their new soil. After a week or two you can begin bringing them in at night and returning them outdoors during the days. After a few weeks or if temperatures drop go ahead and bring them indoors permanently and place in that sunny window. Be sure to inspect them for bugs before bringing inside. This is really a process that is best done slowly to avoid too much of a shock in your plants.
The “bonus” plant I mentioned earlier is the Stevia. This is my first year growing this plant but I have really loved keeping this and would love to have it fresh all year so that I can benefit from its sweetness in my teas throughout the winter. Since this is my first year bringing it in I am still experimenting with it. I put it in a pot and allowed it to get used to the soil before bringing in. Now, it is inside full time and in front of a west facing window. So far it seems to be doing really well. I am a little concerned about how it will do as we lose daylight over the next month or two. I may have to move it to a different window. It likes to be thoroughly watered about once a week.
The key in keeping your herbs inside for the winter is knowing your plants (and occasionally it is also just experimenting). Each one has unique tolerances and requirements that will need to be met in order to be successful. In addition, some are not worth the effort to transplant while others, like expensive plants or those you want to propagate in the Spring will be worth it in the end.