7 Plants That Add Nitrogen to Soil for a Healthier Garden Boost soil healthy naturally with these nitrogen-fixing plants. Close Credit: Steve Satushek / Getty Images Key Points Growing nitrogen-fixing plants is a natural way to feed your soil and help future plants grow better.Vegetables like peas and green beans not only give you food but also return nitrogen to your garden’s soil as they grow.Plants like clover and lupines make pretty, useful ground covers while quietly adding nitrogen to tired or poor soil. Nitrogen is one of the most important components of garden soil as it helps plants build the amino acids they need to thrive. But nitrogen can deplete over time, meaning you'll need to find ways to maintain its presence. While you can amend your soil with fertilizers to replace lost nitrogen, another way to bolster the presence of this element is to grow plants that add nitrogen to the soil. Ahead, we're sharing the nitrogen-fixing plants our gardening experts say to grow in your garden. Kathy Jentz, host of the GardenDC podcast and author of Groundcover Revolution Angela Judd, certified master gardener, author of How to Grow Your Own Food, and founder of Growing in the Garden How to Add Nitrogen to Your Soil for Healthy, Prolific Plants 01 of 07 Peas Credit: emholk/Getty Images When gardeners talk about nitrogen-fixing plants, peas (Pisum sativum) are often at the top of the list. These hard-working legumes are well-known for their ability to fix nitrogen in the soil. "I love planting peas in the spring and fall in my edible garden, both to have as an edible crop and to give my garden soils a boost for the next season of growing," says author Kathy Jentz. "You can just chop down the plants after they stop producing flowers and pods and let the plants decay in place to add even more nutrients back into the soil." Zones: 2 to 11Size: 12 to 18 inches tall x 6 to 12 inches wideCare requirements: Full sun; fertile, well-draining soil 02 of 07 Peanuts Credit: Penpak Ngamsathain / Getty images You might think of peanuts (Arachis hypogaea) as a farm crop, but you can easily grow this plant in a backyard garden, and they don't necessarily have to take up a lot of space. The long growing period (often around 140 days) means that peanuts are typically grown in southern climates that provide the necessary growing conditions. Peanuts are legumes because they grow seeds in pods; they just do it below ground instead of up among the leaves. But they still provide similar nitrogen-fixing properties for the soil. Zones: 8 to 11Size: 18 inches tall x 36 inches wideCare requirements: Full sun; loose, sandy, well-draining soil 03 of 07 Green Beans Credit: brytta / GETTY IMAGES The common bean (Phaseolus vulgaris) is another nitrogen-fixing legume. You might not immediately think of green beans as pod-bearing legumes since we eat them when they're still tender and slim, but they fall into this same category. Beans also improve water and nutrient intake through a symbiotic relationship with fungi in the soil. Zones: 3 to 10Size: 15 to 24 inches tall x 12 to 18 inches wideCare requirements: Full sun; well-draining soil 04 of 07 Fava Bean Credit: Crispin la valiente / Getty Images One of the oldest domesticated crops, fava beans (Vicia faba), also known as broad beans, are great nitrogen fixers. "I fill empty spots in my cool-season garden with these beans," says master gardener Angela Judd. "For the most nitrogen-fixing benefit, I cut them down before they flower and leave the roots in the soil to decompose. I use the tops as a chop-and-drop cover crop to add organic matter before spring planting." Zones: 3 to 9Size: 2 to 6 feet tall x 12 inches wideCare requirements: Full to partial sun; well-draining soil 05 of 07 Clover Credit: Getty Images Think beyond your garden beds—the rest of your landscaping can benefit from nitrogen-fixing plants, too. Clover (Trifolium repens), another legume, can help fulfill this role. "Clover is a great ground cover and turf grass lawn substitute, especially where you get a lot of pet traffic in your landscape," says Jentz. "It does a great job of fixing nitrogen in poor, compacted soils." Zones: 3 to 10Size: 4 to 6 inches tall x 12 inches wideCare requirements: Full to partial sun; various soils 06 of 07 Cowpeas Credit: zhikun sun / Getty Images Cowpeas (Vigna unguiculata), also known as black-eyed peas, are grown for their beauty and many culinary uses, but you can also grow them for their nitrogen-fixing properties. "It’s easy to tuck cowpea seeds into open spots in my summer garden," says Judd. "They’re heat-tolerant, drought-resistant, and help restore tired soil. For the most nitrogen-fixing benefit, I cut them at soil level before they produce beans." Zones: 7 to 10Size: 5 to 10 feet tall x 1 to 3 feet wideCare requirements: Full sun; well-draining soil 07 of 07 Lupines Lupines do best when direct seeded. Credit: schnuddel / Getty Images Legumes aren't the only nitrogen fixers. There are other options, including delightful early summer flowers like lupine (Lupinus), which produces cone-shaped spikes of flowers called racemes. Lupine blossoms can be various shades of purple, pink, white, red, yellow, and orange, all in a strong pastel palette. "Lupines are a good choice of nitrogen-fixing plants and are a perennial with beautiful flowers to enjoy year after year, while it is enriching your soils," says Jentz. "They also are a great pollinator plant—attracting bees, butterflies, and hummingbirds." Zones: 3 to 9Size: 2 feet tall x 1 to 2 feet wideCare requirements: Full sun for most blossoms; well-drained, even sandy soil Explore more: Garden Vegetable Garden Ideas Sources decorvow is committed to using high-quality, reputable sources—including peer-reviewed studies—to support the facts in our articles. Read about our editorial policies and standards to learn more about how we fact check our content for accuracy. Phaseolus vulgaris. North Carolina Extension Gardener Plant Toolbox.