Garden :: GROWING MINT INDOORS, The Kitchn June 2017
Mint is one of those plants that you really cannot mess up. Promise. It can handle the abuse of lack of watering or poor sunlight. The only real risk is that the plant chokes itself (silly, plant!) but that can be avoided easily.
Here's everything you need to know about growing mint in your kitchen.
First, the Basics
Mint is a considered a "runner" — a plant that sends out horizontal root runners, which produce new stalks. This is both good news and bad news for small gardens. Good in the sense that mint will keep on giving and is able to take abuse from lack of watering or poor sunlight; bad because you must pick a pot with enough space for the plant to continue growing in, or else the roots could wrap around themselves in swirly patterns and start to choke the plant. (Weird, right?)
Choose a long, shallow pot to give the plant room to spread. If you can't find a long pot, choose a deep one — whether deep or wide, the root system just needs room to grow.
Skip the seeds and go with a start (a plant that's already started growing) when it comes to planting mint. Why? You're going to want to taste a leaf before you commit to growing any sort of mint. Many peppermints, curly mints, and other plants are sold as mints, but they are not the same as the cool menthol plant you find in a mint julep and will likely disappoint in recipes.
Once you find a variety you like, get it home and plant it in that perfectly selected container. You probably only need one plant (because of all that spreading!), which means you don't have to worry about spacing. Just put the plant in the middle of your container, a few inches into the soil, and it'll spread out.
Mint can be planted any time of year and performs best in full sun, as long as the soil is kept moist, but it also thrives in partial shade. (Again, you really cannot mess this up!) A note on watering: Mint does not like wet "feet," so make sure the soil drains well and do not let water stand in the drainage saucer. As with all plants, you are aiming for a consistent level of moisture in the soil. Don't let it dry out and don't soak it, either.
To harvest, cut halfway down the stems — they will grow back. If the stems are looking spindly or the leaves are small and brittle, cut back the entire stem, as close to the soil line as possible. The more you harvest, the more vigor the plant has, so be generous and harvest a stem or two at least once a week. Once the plant flowers, be sure to cut it back all the way, fertilize it, keep it watered, and it will grow again. (Use a gentile nitrogen-heavy fertilizer such as alfalfa meal, which you can find at your local garden center.)
Keeping the Plant Going
Mint is a perennial plant, which means in an indoor garden you can grow it all year long — although as sunlight wanes in winter, so will the plant's growth. For this reason, unless you have a very sunny (south-facing) winter window, you should cut back your mint every autumn. Snip off the stems as close to the soil line as possible and keep it only lightly watered over the winter. This helps keep energy in the root system and won't stress the plant. While the mint may put on a little bit of growth after trimming, don't expect any real harvest until the season turns and the days start getting longer. Fertilize again in the spring, keep the soil moist and, soon enough, the stems will come back hardy and strong.
If you notice the mint's growth waning after the first or second year, the pot may be overcrowded with the root system. This happens with mint, but here's how you fix it: Turn out the plant, trim some of the roots, and re-pot it with fresh soil. Don't worry about cutting too much of the root system away — mint is hardy and will grow back.
PHOTO CREDIT :: Shannon Douglas