How to Start—and Maintain—an Indoor Garden for Fresh Produce at Home
Even if you don't have a green thumb, this step-by-step guide will help you create an indoor garden for veggies and herbs with ease.
Whether you're been wanting to save yourself trips to the grocery store for fresh produce or the latest pandemic is making you long for a taste of nature, starting a garden seems like the most logical answer to your troubles. But if you're a city dweller without a backyard space or you constantly deal with inclement weather, it's not the most feasible option. One solution: Bring the outdoors—and all its luscious greenery, dirt, and smells—inside with an indoor garden.
Not only does gardening in your humble abode count as a fun new quarantine hobby, it can also have profound health benefits, according to research. Studies have shown that gardening (in or outdoors) is linked to an increase in life satisfaction, psychological well-being, and cognitive function, as well as reductions in stress, anger, fatigue, and depression and anxiety symptoms.
“Plants make me smile and do exactly what the research has found—lower my stress and elevate my mood,” says Melinda Myers, gardening expert and host of the Great Courses’ How to Grow Anything DVD series. “Tending plants, watching them grow, and continually learning as I try new plants and techniques keeps me excited and interested in trying more and sharing what I have learned with others.”
And you don’t need to be a plant master to successfully start an indoor garden. To Julie Bawden-Davis, founder of HealthyHouseplants.com and author of Indoor Gardening the Organic Way, the special touch needed to tend to an indoor garden isn’t necessarily something you’re born with. “I would say that everyone can develop a green thumb,” she says. “It’s like anything else—you need to practice. The more you practice, the greener your thumb will become.
Ready to give indoor gardening the old college try? Follow this step-by-step guide to starting an indoor vegetable garden or herb garden and setting it up for success.
Step 1: Decide which herbs and vegetables you want—and are able—to grow.
Before you dump some soil, seeds, and water in a pot and call it a day, you need to carefully plan out your indoor garden. Ask yourself: “How much room do you have to garden indoors? Will you use artificial light to expand planting options? And what herbs and vegetables do you eat and use when preparing your meals?” says Myers. These questions will help you figure out which herbs and veggies—and how many of each—you’re able to maintain in your growing conditions. If you’re planning on using only natural light in your slightly shady apartment, for example, you wouldn’t want to grow peppers. And if you only have one tiny sunny area of your living space, you probably won’t be able to grow dozens of plants.
The Best Vegetables for an Indoor Garden
Since natural light can be a challenge while growing indoors, Myers recommends choosing plants that can tolerate a bit of shade, such as leaf lettuce, spinach, arugula, and kale. These greens take around 45 days to reach maturity—meaning you can have a fresh salad in a month and a half. As for veggies outside of the greens-realm, Myers suggests choosing radishes, beets, and carrots, which can hold up against some shade, for indoor gardens. If patience is not a virtue you're known for, microgreens are the best bet—these small but nutritionally mighty greens can be harvested just 10 days after planting the seeds, she says.
If you’re hoping for fresh homegrown cherry tomatoes, eggplant, or peppers, you’ll have to put in a bit more effort. These plants need the most sunlight and grow flowers that need to be pollinated in order to create fruit. Unlike leafy greens, root crops, and tubers, which self-pollinate, these plants typically rely on bumble bees and wind to move pollen from the male to the female reproductive structures, according to the Gardening in Michigan extension at Michigan State University. Since there aren’t any bees around your indoor garden to help with that organically, you'll have to do the work yourself by using something such as kids' watercolor paintbrush to transfer pollen from one flower to another, says Myers. Depending on the variety, it’ll take anywhere from 65 to 110 days for the plant to start producing edible goodness, she says.
The veggies you’ll probably want to avoid growing in an indoor garden: Pumpkins, watermelon, and squash—and not just for the obvious size issues. These plants tend to climb, sprawl, and overall take up a lot of space, says Bawden-Davis. Beans and peas aren’t the easiest to grow inside either, as they grow on spreading vines, she adds.
The Best Herbs for an Indoor Garden
For indoor herb gardens, choose basil, chives, mint, oregano, parsley, sage, and thyme—flavor boosters that often thrive indoors and under most gardeners’ care, says Myers. Rosemary and bay leaves can be a bit more challenging to maintain, while cilantro likes cooler temperatures and requires several plantings to build up enough supply to actually use in your cooking, she adds.
Using Food Scraps for an Indoor Garden
While you’ve probably seen those Facebook videos that show someone loading up a pepper with soil, followed by a time-lapse of a stem growing straight out of the veggie, growing with any food scraps you have lying around the kitchen isn’t that easy. It’s not always the most productive way to grow vegetables, but it can be done, says Myers. Potatoes, sweet potatoes, celery, and onions tend to work best with this method.
Starting peppers and tomatoes from seeds left from last night’s dinner takes a lot of time, and you might end up with something that tastes and looks very different from the vegetable you collected seeds from, says Myers. The reason: The types of veggies you get at the grocery store are hybrid plants, meaning it was created by crossing plants from two different “pure lines,” or lineages of plants that have been inbred. Since this hybrid plant contains genes from two distinct family lines, its offspring will have a random mixture of genes from the original pure lines, giving you both desired and unwanted characteristics, according to South Dakota State University.
Step 2: Choose between a soil-based or hydroponic indoor garden.
Using pots filled with soil is the most common way to grow herbs and veggies indoors, but it's not the only way. In indoor gardens, potting soil helps anchor the plants, provides air space for oxygen to get to the roots, and serves as a reservoir for water and nutrients, says Myers.
However, hydroponic gardens, which involve growing plants directly in water sin soil, are becoming more popular. In this growing system, freshwater helps provide oxygen to the roots, and liquid fertilizer is added to the water to give plants the necessary nutrients typically found in soil. “Hydroponic growing takes knowing the correct mix of nutrients to put in the water, so it can be a little more complicated than planting in the soil,” says Bawden-Davis. “However, there are hydroponic growing systems like Aerogarden that make it easy to do.”
Deciding whether to use a hydroponic system such as an Aerogarden (Buy It, $169, amazon.com) or pots with soil all comes down to your price point and growing space, says Myers; hydroponic gardens tend to have a high price tag, but they often come with artificial lighting so you can grow anywhere.
Step 3. Figure out your indoor garden location.
In general, the best location for an indoor garden is the area with the best light, says Bawden-Davis. Putting your plants up against a window is A-OK—under the right conditions. If you have northern-facing windows, plants can sit directly on the sill, as the light isn’t so intense and hot that it will harm them. Western-facing windows, however, may be too hot, and plants will need to be placed two to three feet away from the windows, says Bawden-Davis. Your local climate matters, too: Gardeners in the North may need to back their gardens away from cold windows in the winter, says Myers. You should also avoid placing your indoor garden where it could receive drafts of hot air (think: heating vents) or cold air (like the air conditioner), which can damage plants, she adds. (Related: How One Woman Turned a Passion for Farming Into Her Life's Work)
If your only available indoor garden space has zero sunlight, you’ll need artificial lighting. This full-spectrum artificial light (Buy It, $15, amazon.com) simulates daylight and is available in various types of bulbs, including ones you can screw into light fixtures you already have in your homes, says Bawden-Davis. Just make sure to position these grow lights directly over the planters for the best results, notes Myers. To give your indoor garden an extra boost of sunshine, consider placing pots on a reflective or white surface, which will bounce light back into the plants from below, she adds.
Step 4: Choose containers to grow your produce in.
If your indoor garden is going to be soil-based, pick up containers that are suited to the plants you’re growing. Tomatoes and peppers need at least a one- to two-gallon pot for smaller varieties, and a three- to five-gallon pot for larger, while greens can grow in most sizes of containers, says Myers. To ensure each plant’s roots have enough room to grow (important for giving the plant enough energy to produce veggies), use separate containers for each large vegetable plant, though multiple plantings of small greens and root crops can be grown in the same container if there’s enough room for them to reach their full size, she says.
Along with the size of the pot, the features of the container itself can make or break your indoor garden. Opt for plastic containers, which are lightweight and hold moisture longer, and those that have drainage holes to prevent the soil from becoming overly saturated, says Myers. “I like to place my containers on trays or saucers filled with pebbles,” she says. “The excess water collects in the pebbles and the pot is elevated above the excess water to avoid root rot. It also saves time pouring off the excess water each time I water my plants.”
If you’re more of a “set it and forget it” person, consider buying a self-watering container—a style of pot featuring a water storage tank underneath the plant. Much like a dry sponge quickly absorbing any liquid it comes in contact with, parched soil will pull water up from the reservoir when it needs it. The result: Instead of watering a few times a week based on your intuition—running the risk of overwatering or under-watering—you only need to fill the water reservoir when it’s running empty. This extends the time between watering and helps those who tend to neglect their plants or don’t know when to water, says Myers. She recommends a self-watering planter with the TruDrop System (Buy It, $139, amazon.com)
Step 5: Load it with soil.
Whatever you do, don’t dig up some soil from your backyard or neighbor’s outdoor garden and pour it into your pot. Instead, use a quality potting mix, says Myers. Potting mixes have a balanced mixture of peat, compost, or coir (the fuzzy fibers of a coconut shell) to hold moisture, as well as vermiculite, perlite, or rice hulls to promote proper drainage, she explains. The soil from an outdoor garden, on the other hand, may not hold enough water (or hold too much), be depleted of essential nutrients, or be too heavy and dense, which can pack together tightly and make aeration difficult. (Related: Your Guide On How to Make a Compost Bin)
When choosing a potting mix, look for one that’s light and fluffy, and if you’re going for organic veggies, use a mix that’s certified and labeled by the Organic Materials Review Institute, says Myers. Aside from good ‘ol dirt, potting mixes may contain fertilizer, so be sure to check the bag, so you know how often you should be fertilizing. Some boast a “starter charge” of fertilizer that’s used up after two or three waterings, while others, labeled controlled-release, time-release, or slow-release, include a fertilizer that provides small amounts of nutrients over a long period of time, explains Myers. If your chosen potting soil doesn’t contain fertilizer from the get-go, consider adding one that contains the right amount of nitrogen for vegetables plants (which need less than leafy plants and grass) and slow-release to provide a steady flow of nutrients. Nitrogen is the key nutrient for plant growth and helps create lush, green leaves, which then help capture the sun's energy, convert it to sugar, and ultimately create delicious vegetables, per the Northeast Organic Farming Association. “It reduces your workload, and I am all about that,” she says.
You can also add moisture-retaining products to help hold water near the plant roots and reduce the frequency of watering. One sustainable, organic option: Wild Valley Wool Pellets (Buy It, $11, wildvalleyfarms.com). “It can be incorporated into the potting mix to reduce watering by up to 25 percent,” says Myers. This feature makes it extra important not to overwater your indoor garden, as plants growing in soil that is too wet won't be able to get enough oxygen, leading to root death, stunted growth, and yellowing leaves, according to the Missouri Botanical Garden.
Step 6: Plant those seeds, transplants, or scraps.
Once you’ve picked up your containers and soil for your indoor garden, it’s time to choose your seeds. You’ll probably have the best selection with online seed companies (try: Sustainable Seed Company, Baker Creek Heirloom Seeds, or Johnny’s Selected Seeds), but your local garden center will likely carry them in the spring, says Myers. Pick up seeds that have a high germination rate (meaning many of the seeds end up sprouting) and are dated for the current season, she says. While some seeds can last for years when managed correctly and kept in a cool, dark place, the germination rate usually declines with age. Your best bet: Passing over the discounted seeds that were packaged two years ago and grabbing one dated with the current year instead. You should also look to the label for the estimated size the plant will get once it’s full-grown, says Bawden-Davis. “If it gets much bigger than two feet or so tall and wide, it’s probably not a good choice for indoor growing, as it will get too big,” she explains.
When planting seeds, place them at the depth recommended on the packet. Keep the potting mix slightly moist (think: a sponge that has been wrung out) until the seeds sprout and the seedlings begin to grow, suggests Myers.
In the summertime, you might be able to score transplants from garden centers, which take less time to get to the point of being ready for harvest than seeds. Plant the transplants at the same depth as they are growing in their original container. Once the plants have successfully rooted and started producing new growth, you can harvest a leaf or two as needed, and this regular picking will actually encourage the plants to continue producing, says Myers.
Planting Food Scraps
Some of the best vegetables to grow from food scraps are those that produce shoots—aka sprouts—as they age or when placed in water. These shoots are the new growth from seed germination within the vegetable and are where leaves will develop. Some vegetables, like carrots, turnips, and other root veggies, will only re-grow their top leafy greens when placed in water. Onions, garlic, scallions, and leeks grow shoots when their stems or bulbs are placed in a shallow dish of water, while sweet potatoes begin to sprout at the tip when left in the pantry too long. To grow potatoes from these scraps, cut the sprout off a few inches below the growing point, plant in potting mix, and water as needed. For regular potatoes, which sprout across the vegetable, cut the potato into pieces so that each chunk has a sprout or two. Plant in potting mix and water as needed.
To grow herbs from scraps, cuttings may be used. Choose a three- to four-inch cutting of a firm stem with leaves, remove the lowest leaf, and stick it in a moist potting mix. Keep the potting mix moist until roots form, about two weeks, then reduce watering frequency. Keep the potted cutting in a bright location out of direct sunlight, and move to a brighter location once rooted.
Step 7: Water your indoor garden.
How often and how much you water your indoor garden plants all depends on your growing conditions and the age of your plants. In general, “the warmer you keep your house, the lower the humidity, and the sunnier the location, the more often you will need to water,” says Myers.
For seeds that have sprouted and began to grow, gradually extend the time between waterings and water thoroughly when the top few inches of soil are starting to dry, making sure to pour out the excess, says Myers. With newly planted transplants, keep the top few inches of soil slightly moist for the first few weeks, then gradually reduce your watering frequency as the plants become more established, she says.
A good rule of thumb: “If the soil is dry when you stick in your finger or a moisture meter, then it’s time to water,” says Bawden-Davis. And tap water is typically fine to use for your indoor garden, but if your plants look to be affected by the minerals in your tap water and are getting brown leaf tips, try switching to filtered water, she adds.
Step 8: Fertilize your indoor garden.
If the fertilizer in your potting mix or the slow-release fertilizer you added at the time of planting has run its course (the packaging will tell you how long it lasts), you’ll likely want to continue using some kind of fertilizer, especially if your plants are showing signs of nutrient deficiencies, including pale leaves and stunted growth. You can continue adding slow-release fertilizer as directed on the label, or use liquid fertilizers that are added directly to the water, says Myers. Opt for one designed for flowering plants or a balanced fertilizer, which has the same amount of nitrogen, phosphorus, and potassium—the three fundamental nutrients in plant nutrition. These fertilizers are applied every two weeks or month (again, check the label), but consider starting with a diluted solution, as fertilizer recommendations are usually designed to achieve the maximum level of growth and could actually be more than your plants require, says Myers. Over-fertilizing your plants can cause sudden, immense growth, but the roots may not be strong and large enough to supply the plant with enough water and nutrients, possibly reducing the number of vegetables it can produce.
If you’re using a granular fertilizer, make two-inch deep holes, one to three inches apart in the soil with a tool that’s smaller than the diameter of a pencil. Then, sprinkle the fertilizer directly into the holes and cover with soil and water, says Bawden-Davis.
Step 9: Don’t get discouraged.
Whether you think you have a green thumb or not, know that it’s totally normal if your kale plant shrivels up or your basil looks sad and droopy, so don’t call it quits before you take a bite into something you’ve grown with your own two hands. “Everyone that gardens kill plants—it’s part of the learning process,” says Myers. “And don’t be afraid to ask for help—gardeners love to share their knowledge, passion, plants and produce.”