If you love summer gardening and get a little blue when winter comes around, fret not! You can still grow vegetables indoors, it’s just a different set-up. Most tasty plants like a good amount sunshine, so you will have to offset the shorter days with a few choice grow-lights.
Sunny windows may suffice for a while, but seedlings will eventually get leggy, and production will be minimal, if at all. You’ll have to manage expectations, as well, since growth time will be significantly slower.
Some species may not be worth the effort, especially when there are other things you can propagate instead. Here are some vegetables you can grow indoors in winter with good results.
Herbs are great when you don’t have a lot of growing space since they don’t need a large container. Most herbs enjoy full sun, so find a window sill or shelf that gets a lot of southwest-facing light. Certain species like basil, lavender, and rosemary may need supplemental lighting with a grow light, but there are some like oregano, mint, and parsley that can flourish without extra light, giving you fresh additions to your meals all season long.
Lettuce is a cool-tolerant crop that grows rather quickly without needing a deep container (four inches will do), making it a popular choice for indoor growing. Even on a sunny windowsill, lettuce will benefit from a fluorescent shop light hung above, but these salad greens aren’t as needy as other veggies like tomatoes or peppers.
An average sized indoor pot will do for one plant, or use a wider planter for more. Try sowing seeds every couple of weeks so that you continually have a fresh crop on the way. Pinch or cut outer leaves from the base of mature plants (at least six inches tall), and the center of the plant will keep growing.
Baby Salad Greens
Arugula, spinach, and kale all require the same kind of growing conditions as lettuce, and can be harvested early as “baby” greens. You can grow them to maturity, as well, but quick harvest times give you available salad greens while you wait for other things to develop. They can be potted together and grown as a salad mix. Arugula can be cut at the base when it’s only a couple inches long. Kale and spinach can also be cut when they are young (about 15-30 days), which is why they are referred to as “baby” kale or spinach – they are not a different species!
Microgreens are exactly what they sound like: really tiny plants! Growing microgreens is fun because you can choose a mix of various vegetables to grow, and while they do need light and good airflow, supplemental grow lights may not be needed since you are harvesting when they are quite small. Microgreens are packed with nutrition and won’t take up a lot of space or time, either. You only need a shallow container with a couple inches of soil.
Follow packet guidelines for planting instructions and use germinating potting soil for best results, keeping it moist with a gentle spray. When the seedlings have two leaves, usually around one to three weeks of growth, harvest with a sharp pair of scissors at the soil line. Secondary growth may occur, but it’s not hard to start the whole process over again.
Some people think sprouts and microgreens are the same thing, but they are actually quite different. Sprouts are grown in water and harvested within 3-5 days. The process is simple: soak specific “sprouting” seeds overnight, and then rinse, swirl, and drain once a day until sprouts have germinated and matured to your liking.
Unlike microgreens, you eat the whole plant, seed included, which is packed with fresh enzymes and other nutrients that are hard to come by in the winter. Since sprouts are grown in water and stay humid, bacteria can sometimes thrive, so rinsing well is an important part of the process. Otherwise, these nutrient-dense snacks take up little space, and don’t need any light to do their thing.
Scallions or Garlic Greens
Onions and garlic need a lot of space and won’t grow well indoors in the winter, however, the tops of them will! You may have already noticed the thin greens that sprout from an onion or piece a garlic that has been on the counter a little too long, and the process is that simple.
Place scallions in water and wait for it to root out a couple of inches, then plant in soil. Harvest just the tops and allow to regrow, or use the whole scallion. Garlic cloves can be sown into potting mix and in about a week or so, greens will grow out the top. Easy, peasy.
Snap and snow peas are the best varieties to use for indoor growing. These climbing plants will appreciate a trellis as they grow upwards, reaching for their light source. A sunny window will be enough for a while, but extra grow lights will ensure that they eventually produce pods.
They aren’t as fast growing as the cool-tolerant leafy greens, but they are beautiful to watch grow along the way, even if you aren't yielding large baskets. They can also be the first to head outside once the ground is workable in early spring, since they can tolerate light frosts.
I’m adding this one because everyone needs a challenge! Place the unblemished pit of an avocado halfway into a pot of dirt, and within a couple weeks, a tiny plant will emerge from the top. These tropical plants love the sun, so once they get going, they will need their own grow light in the winter or your beautiful tree will drop all of its leaves and wither away right before your eyes. (Yes, this has happened to me).
You may only get one or two avocados, and it may take a couple of years, but the fun is in the trial, and it makes for a beautiful indoor plant that you can bring outdoors in the summer.
The most important thing to acknowledge is that not everything you grow outside will work indoors. It may be tempting to try and produce strawberries and tomatoes, but they will require a ton of extra light and care - best save that for late winter seed-starting so you can have a good summer harvest.
For success in growing food indoors, stick to what will yield results without too much extra space or lighting needs. Try your green thumb at any of these veggies, and you will find success with what you can grow indoors in the winter.