Lentil Grow Guide: How to Grow and Care for Lentils

Lentils (scientific name Lens culinaris) are a small, oval-shaped member of the legume (or Fabaceae) family, sometimes referred to as “pulses.” The legumes are a great cool-weather crop that you can plant just before the last frost date of the growing season.

Lentils are common crops in Asia and the Mediterranean; in North America, lentils are commonly grown in dry, cool places like eastern Washington, Idaho, and western Canada to avoid stunting the plant with high humidity or high temperatures.

The dry lentils that you purchase at the grocery store are the seeds of the lentil plant. These seeds grow inside pods (just like green beans or snap peas) on slender, flowering bushes that thrive in the cool season of early spring.

There are numerous lentil varieties to grow in the garden, and each plant will result in different flavors and textures of lentils. The most commonly grown lentil varieties include:

1. 1. Brown lentils: Flat, brown lentils are the most common lentils to find at the grocery store, with an earthy flavor and a firm texture.
2. 2. Yellow and red lentils: Small red or yellow lentils have a sweeter, nuttier texture and a soft, sometimes pulpy texture.
3. 3. Green lentils: Large, pea-shaped, green lentils have a peppery flavor and remain very firm, even after cooking. Learn more about cooking lentils.

If you’re new to planting lentils, here are a few tips to help improve your harvest:

1. 1. Try inoculation. Many growers of pulse crops add an extra step to their planting routine: inoculating the seeds with a special bacteria that helps encourage nitrogen-fixing, strengthens the plant, and improves the yield. Inoculate your lentils by mixing the lentil seeds with the inoculant Rhizobium leguminosarum, which is commercially available at many garden stores. Allow the seeds to dry in the shade before planting.
   
2. 2. Follow companion planting procedures. Lentils grow well with most garden plants, since lentils are nitrogen-fixers, meaning they have healthy bacteria-filled nodules on their roots that replenish the soil with necessary nitrogen. Popular companion plants include summer savory and cucumbers. However, avoid planting lentils next to alliums like onions or garlic (or in a spot that recently grew these alliums) since they can release a chemical that inhibits growth in legumes. You may also want to avoid planting lentils too close to plants susceptible to the same diseases, like potatoes or soybean plants.
3. 3. Consider trellises. Lentil pods can become heavy and weigh down the delicate branches of lentil plants, so using a support structure like a low trellis or tomato cage can help keep your plants upright. Support structures have the added benefit of keeping your plants’ stems separate, allowing airflow to prevent disease and foster drying for a quick harvest.

Lentils are a frost-tolerant cool-weather plant, so the best time to start them is in early spring, two or three weeks before the last frost date in your area. Once your weather is right:

1. 1. Prepare the planting area. Lentils grow best in full sun, so choose a spot that gets at least six hours of sunlight per day. The plant thrives in very loose, sandy soil with good drainage and rich in organic matter but can’t tolerate waterlogged soil.
2. 2. Inoculate the seeds (optional). If you want to inoculate your lentils to improve your yield, mix your lentil seeds with the inoculant Rhizobium leguminosarum, which is commercially available at many garden stores. Allow the seeds to dry in the shade before planting.
   
3. 3. Sow seeds. Plant lentil seeds in rows, with each hole one-inch deep, leaving one inch of space between each hole. Space each row roughly 18 inches apart.
4. 4. Water. Water immediately after planting to set the soil, then keep it evenly moist for germination.
5. 5. Thin. Once your lentil seedlings are about three inches tall, thin them with gardening shears, spacing the plants four to five inches apart.

Once your lentil plants are growing, care is simple:

1. 1. Water them. Lentils enjoy evenly moist soil, though they can tolerate short periods of drought. They do not tolerate waterlogged soil, so aim to keep them more dry than soaked.
2. 2. Fertilize them. For the best lentil crop, side-dress your lentil plants twice in the spring with compost tea or another natural fertilizer.
3. 3. Weed around them. Lentils have difficulty competing with weeds, so keep the beds free of weeds or other competing plants.
4. 4. Keep an eye out for pests. Lentils can be targets for aphids, weevils, Lygus bugs, wireworms, and thrips. Pinch individual pests off the plants or remove them with a blast of water—for infestations, use a natural pesticide.

Around 110 days after sowing, your lentils should be close to harvesting:

1. 1. Taper off the water. Once the lentil pods at the bottom of your plants begin to harden and turn brown, stop watering your lentil plants to encourage the pods to finish drying.
2. 2. Pull up and dry the plants. After the lentil pods on the lower branches are brown, pull up the lentil plants and lay them out either in a sunny, dry place outdoors or in a room with good air circulation. Leave the plants for about a week until the pods are fully dry.
3. 3. Separate the lentils from the plants. Once the pods are dry, remove them from the plants by picking them off the stems, shaking the plants, or putting them in a bag and crushing them. Shell the pods by breaking them open and revealing the seeds. You may want to winnow the harvest afterward. Winnowing involves transferring the pods between two buckets to allow the wind to separate the light pieces of leaves and stems from the heavier pods.
4. 4. Store. Store shelled, dry lentils in an airtight container in a cool, dry place. Dried lentils will last up to a year.

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