You can’t beat homegrown edible plants for high-impact flavor and nutrition. The longer they go from soil to fork, the weaker their content — from flavor-enhancing sugars to immune-system-boosting antioxidants.
If winter’s slate-gray skies have you pining for the homegrown veggies from your summer garden, take heart. Even novice growers can produce nutrient-packed food indoors, all winter, with some basic tips and equipment. Whether you are growing fresh greens, scallions or herbs, you can add some novelty and nutrition to your winter meals while staying connected to nature as the outdoor garden snoozes.
Success with indoor edibles is an exercise in perspective. “Indoors, a single pepper is a huge achievement,” says Shaun Murphy, owner of Indoor Sun Shoppe in Fremont. The lack of airflow, abundant light and beneficial insects to control pests indoors all make it a challenge to grow most of what we think of as “outdoor plants” inside. For the most abundant growth, you need grow lights, if not a greenhouse, so for this article, we’ve focused on ways to harvest fresh food without significant investments.
The local garden experts interviewed all agreed that growing microgreens delivers the biggest harvest for the least effort indoors. “Big” here refers more to volume than size — the greens are usually harvested at between 1 and 2 inches high. Often sold at a steep price-per-pound in upscale supermarkets, you can grow microgreens yourself in only about two weeks.
Another bonus: The tiny seedlings may have as much as 40 times the nutrient content as their full-grown counterparts, research out of the University of Maryland has found.
Murphy says microgreens are an ideal project for people new to growing edible plants indoors. “For the cost of a $4 pack of seeds and a 50-cent saucer, people will have some success with microgreens,” he says.
Selena Ligrano, a project manager for Seattle’s Tilth Alliance, agrees that growing microgreens is “a great way to add texture, color, flavor to sandwiches, salads and stir fries.” If you’re a smoothie drinker, level-up your homemade concoctions by adding greens for extra nutrients.
In addition to its paid programs, Tilth Alliance offers free classes to groups like housing authorities and community garden groups. The microgreens class is a hot ticket every winter for people with limited indoor space.
“This time of year, it’s a lot of trying to identify what can grow indoors. Our class in growing microgreens is very popular because you can get such a wide variety of different plants to grow, and you don’t need an extensive setup,” says Ligrano, who is a project manager and answers questions on the group’s Garden Hotline.
So what are microgreens? Basically, they’re any edible plants grown in a shallow planter and sown thickly, and that are typically harvested after the first true leaves have appeared.
You can grow most edible plants as microgreens. While legumes (peas and beans) and brassicas (including broccoli, kale and arugula) are the most popular, Ligrano enjoys growing cucumbers and melons as microgreens, as well, because the leaves carry traces of the flavors to come.
“You’re going to get a nutty flavor from sunflower, a sweet one from peas and a spicy one from radish,” she says.
Murphy says that, like most plants in light-challenged Seattle, microgreens will grow fuller and straighter with a grow light — but because they are harvested so early, you don’t reach the stage when seedings get leggy.
With successive plantings, you can enjoy greens all winter. Microgreens are sometimes billed as a cut-and-come-again crop, but Murphy has found that the regrowth is so weak, it makes more sense to start a new batch. Also, in seed mixes containing clover, the fast-growing clover will often overtake the other plants as they mature.
Murphy says you can grow microgreens in a half-inch-deep container with drainage holes, placed on a sunny windowsill, with tasty results. He’s been known to use a saucer. Indoor Sun Shoppe carries seeds, growing trays, planting media and lights if you want to go all-in.
A well-draining soil or potting mix, such as coco coir or seed-starting mix, works best. For this stage of their lives, the seeds have their own resources and need no extra fertilizer.
When sowing, “Imagine you’re sprinkling a pepper shaker, putting a lot of seed in one area,” says Ligrano. “You want almost like a lawn-dense patch of greens coming up.”
Colin McCrate, founder of Seattle Urban Farm Company, a firm that designs edible gardens, says microgreens need minor but frequent attention, especially when watering.
“There’s a little bit of a dance between making sure they’re moist and not overly moist,” he says, to avoid issues like damping off, a fungal disease that can weaken or kill seedlings.
McCrate recommends sowing in a nursery flat with drainage holes that’s set on a tray or baking sheet. He likes to water from overhead until seeds germinate (sprout) and then “bottom water” via the tray, reducing humidity around the stalks — and decreasing the chance of knocking them over with a blast of water.
What are McCrate’s favorite microgreens? “Broccoli makes a really good microgreen, but the seed is significantly more expensive. If you’re growing brassicas, mustard greens are less expensive,” he says, but still spice up salads. Pumpkins “have a nice, fresh taste and texture,” and he likes cilantro and basil, too, for an easy way to cultivate herbs.
Speaking of herbs, Instagram and Pinterest are loaded with mouth-watering images of indoor herb gardens, but if you lack grow lights, your harvest will vary. You may not be able to grow a big enough batch of basil to make pesto, for example, but you may be able to garnish your pasta every other week or so. Basil loves heat, which makes it a good candidate for indoor conditions. Other potential winners Murphy suggests are chives, oregano and mint.
“I’d probably buy a plant and see how it goes — they’re going to grow weaker, maybe not have as much flavor indoors,” says Murphy. You can buy soil-grown potted plants or bagged ones in water — refresh the water every couple of days for the hydroponically grown herbs. Or, like McCrate does, try growing cilantro or basil as microgreens.
You may have heard about re-growing supermarket vegetables such as lettuces and onions from their scraps, and yes, you can reproduce this minor miracle. The caveat is that you’ll regrow only the green growth — so scallions will work well, but other bulb onions won’t sprout a new bulb.
“I have two jars of green onions on my counter right now,” says Tilth Alliance’s Ligrano. It’s crucial to have some of the root system to start with (the white stalk on onions, the core in lettuces), she says. Then partially cover that root area with water in a jar and change the water every three days. Celery works, too — the stalks will be floppier, but can still elevate your sauces and soups.
Sprouts have had mixed press due to food poisoning outbreaks from mass-produced varieties, and our experts were divided on growing them at home. Some feel they require more expertise or attention than is ideal for new gardeners. However, grown with care, they are a highly nutritious crop that needs no soil or light and takes up very little space. Some popular seeds to sprout are alfalfa, wheatgrass and lentils.
“We’ve been growing them at home for years and have never had a problem. I feel like it’s probably a lot less likely to happen from something you’re growing at home rather than [something from] the store,” McCrate says of bacterial contamination.
He uses quart Mason jars for sprouting, with a mesh-screen lid that you can make or buy. (You can also use a cloth held with a rubber band). The next steps are rinsing the seeds, soaking them in cool water (about 70 degrees) until they have doubled in size (time varies per seed), draining them by tipping the jar on its side into a bowl, and then rinsing them twice a day.
The jar stays tipped or upside down to provide the seeds with enough humidity to grow while preventing them from sitting in water, McCrate says. In about a week, the jar will be full.
“We do a lot of brassicas, like kale, cabbage, broccoli, mustards and arugula. And you can also do snap beans, soybeans and lima beans,” McCrate says.
Doug Evans, author of “The Sprout Book,” recommends sourcing organic sprouting seeds that have been tested for pathogens. Sanitize your containers before use and use filtered water to reduce potential contaminants. Culturesforhealth.com, which sells various sprout kits, adds these safety tips: Let sprouts dry before refrigerating them, and consume them within 5–7 days.