Growing cilantro (Coriandrum sativum) in the kitchen garden takes minimal effort with lots of tasty rewards. This fast-growing annual herb grows rapidly and is ready for harvest within 45 days of planting. Once you harvest the first round, cilantro will keep coming back until summer temperatures cause this heat-sensitive plant to bolt. With regular water, the right nitrogen fertilizer and plenty of light, you can grow cilantro successfully.
Planting Depth and Spacing
Although you can plant cilantro from pre-started seedlings, this herb is best started from seed because its roots don't handle disturbance well. Plant the seeds 1/4 to 1/2 inches deep. Start with a spacing of 2 inches between seeds, then, as the plants mature, thin them out to a 4-inch spacing. Cilantro needs full sun and frost-free but cool temperatures to thrive. Ideally, plant cilantro in spring after the last frost date. Cilantro grows well until temperatures rise above 85 Farenheit. When it gets hot, cilantro goes to seed rapidly.
Water Seeds and Seedlings
Water cilantro seeds right after you plant, and follow up through the growing season with about 1 inch of water a week. Make sure the soil stays moist until the seeds germinate -- about seven to 10 days after planting and until the seedlings start to leaf out. Once established, cilantro plants grow better when the soil is allowed to dry out slightly on top between watering.
Fertilize with Nitrogen
Cilantro needs a nutrient boot during the season with a high-nitrogen fertilizer such as a 21-0-0 formula. (Nitrogen comes first on the fertilizer label.) Sprinkle the fertilizer evenly over the cilantro bed using 1/4 cup for each 25 square feet. Apply the fertilizer when the seedlings get about 2 inches tall. Always follow up with a thorough watering to moisten the soil and release the fertilizer nutrients into it. Fertilize again midway though the growing season.
Harvesting Again and Again
Harvesting cilantro starts early and continues until it gets hot. You can start cutting leaves as soon as the stalks get 6 inches tall. Use scissors to clip the stems about 2 inches from the top of the soil. Keep up on watering, and new leaves will continue to grow after each harvest until it gets above 85 F. After each harvest, wash the scissors with soap and water or dip the blades in a 1-part bleach to 9 parts water solution to disinfect them.