How to Grow Vegetables Indoors

Windowsill

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The onset of winter does not need to be the end of growing and harvesting your vegetables. People who do not have outdoor space grow vegetables indoors all the time. It does have its challenges, and you may not yield as much, but it is possible. Take a look at some of the easier vegetables you can grow indoors.

  • 01 of 09

    Carrots

    Close-up of fresh carrot in pot of soil
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    Carrots are ridiculously accommodating. Growing them in containers is not just a great option for indoor growing; it also solves the problem of trying to grow them in heavy, rocky soil. Smaller carrots are easiest to grow inside. They need less space and mature quickly. A long container, such as a window box, is ideal. Lightly cover the seeds with some damp peat moss, so the seeds don’t dry out. Do not let a hard crust form over them; this prevents germination. Keep the soil moist, and seeds should germinate within two weeks. Days to maturity will depend on the variety you are growing.

  • 02 of 09

    Garlic Greens

    Garlic plant grown indoors in jar
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    If you have ever left a garlic bulb alone for a few weeks or you have put garlic it in the fridge, you might notice a garlic clove sprouting a little green foot from one of its ends. Instead of tossing it out, you can plant that sprouting garlic clove about 1-inch deep in a 4-inch container and water it. Within weeks, you will have garlic greens.

    Start harvesting when they grow to 8 to 10 inches long. Cut off what you need and leave the rest. You generally only get one flush of growth from each clove. They may sprout again, but the quality declines, so start new cloves when you begin harvesting the current crop. These garlic tops taste a lot like garlicky scallions. Don't plan to yield a bulb of garlic. You would need a particular temperature to start forming bulbs, and that won't happen indoors. But, garlic greens are an excellent substitute.

  • 03 of 09

    Hot Peppers

    Growing ornamental hot peppers
    Marie Iannotti

    Pepper plants are tropical perennials. They shrivel at just the hint of frost, but while indoors, they can thrive. Plant some sweet or hot peppers from seed or pot some plants from your garden in late summer and bring them inside. You might not get a huge harvest, but they will fruit.

    Use a container that is at least 8 inches tall. Hot peppers will need at least 10 hours of light each day. Don’t overwater. Allow the container to dry out between waterings. The plants are self-pollinating, but you may need to help them along. You can either jostle the plants to shake the pollen from one flower to another or use a cotton swab to dust each flower with pollen.

  • 04 of 09

    Lettuce and Other Salad Greens

    Person planting lettuce in a wooden box
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    Lettuce is quick growing and shallow-rooted, so it will not need a deep container. It will also continue to regrow if you go the cut-and-come-again route. Choose a container that is two to four inches deep and fill it with dampened soil. Sow your seeds by gently pressing them into the surface of the soil. Mist to keep the seeds moist and you should see germination within about one week. Allow the plants to grow at least four to six inches before you start harvesting. Cut or pull the outer leaves and allow the center of the plant to continue growing.

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  • 05 of 09

    Microgreens

    Radish (Daikon) leaves
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    Microgreens are tiny, fresh sprouts that are probably the most effortless edibles to grow indoors. They don’t take up much space or much time. They are a mix of seeds from various greens and herbs, such as beets, radishes, kaleSwiss chard, and basil

    Since these greens will be harvested as seedlings, you don’t need much soil. A shallow (two inches deep) tray works well. Fill it with soil, moisten it, and scatter your seed. Barely cover the seed with dirt, but press gently so that the seed makes good contact with the damp soil and won’t dry out. Water with a gentle stream or spray to keep the soil moist, and you should see germination within a few days. Start harvesting when seedlings have developed two sets of true leaves. Use scissors to snip them off at the soil level, and you may get another spurt of growth.

  • 06 of 09

    Scallions

    Growing scallions indoors
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    You can’t grow bulb onions indoors, but scallions like garlic greens, do just fine. They may rival microgreens with their ease. You don’t even need seeds. Some gardeners have had success also replanting the root end of scallions after using the tops. You can root the whole scallion in a glass of water and plop the bunch of them in one glass with only about one inch of water in the bottom. When the roots have reached a couple of inches in length, move them to a shallow container of potting mix and let them continue growing. You can harvest just the green tops, leaving about one inch of the stem to regrow or pluck entire scallions out of the container to use the white portion.

  • 07 of 09

    Tomatoes

    Reisentraube Tomatoes
    Marie Iannotti

    Tomato plants are tropical perennials, they die off at the end of the season, usually returning the next year. If you have a large tomato plant, leave it there. But, if you want tomatoes year-round indoors, start a new plant from seed at the end of summer. Tomato seeds germinate fairly quickly.

    Once the seedlings are 3 to 4 inches tall, move them to a permanent pot and make sure they have at least 10 hours of light per day. The lighting sounds excessive, but if you want fruits, that is what this plant needs all year. Use a water-soluble organic fertilizer after repotting. Once the plants start setting flowers, shake them periodically to allow the pollen to fall from flower to flower. You need to perform this manual pollination; without it, no fruits will form. You can expect the plants to become top-heavy, so staking or using a tomato cage is a must. 

  • 08 of 09

    Pros and Cons for Indoor Gardening

    When gardening indoors, you ultimately control all aspects of the plant's growth and environment. You maintain its water, soil quality, and, even, manually fertilize the plants. A big plus is that your plants are not at the mercy of the weather or outside critters, and you have vegetables year-round. At the same time, you improve the air quality around you—plants remove carbon dioxide and produce oxygen. 

    The biggest challenges of growing edibles indoors include a lack of light levels, pollinating insects, and wind. Wind or proper air circulation is vital for flooding the plant with more carbon dioxide as well as pollinating flowers. Also, no matter if you are inside or out, some bugs and plant diseases can follow your plants if you bring them inside for the winter. 

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  • 09 of 09

    Growing Tips

     Consider these suggestions for growing vegetables indoors:

    • Containers should have ample holes to allow for adequate drainage and be sized correctly for the particular plant. Shallow and rooted greens may only need about a two-inch depth, but deep-rooted tomatoes will need at least 12 inches of soil.
    • Use a good quality potting mix, not garden soil. Potting mixes usually have vermiculite or perlite, which allows for better drainage. Garden soil is also not sterile; it may contain fungus or bacteria.
    • In the winter, sunny windows do not provide enough light for healthy, stocky plants. Winter days are shorter, and the sun is too low in the sky. Consider some type of supplemental lighting; either get a plant light or a full-spectrum fluorescent light.