I find it odd that some people just detest cilantro, considering my strong feelings for this delightful herb. Sometimes called Chinese parsley, cilantro is a mainstay of ethnic cuisines the world over, from Mexican to Indian to Thai. The leaves are used as typical cilantro, and the seeds are known as coriander. In truth, cilantro is not the easiest herb to grow. It's delicate. But that's part of the reason we have to grow it: finding decent cilantro in a supermarket is a challenge.
Still, I find the Mediterranean herbs to be much easier to grow, and cilantro can be downright difficult to start from seed. Yet next to basil, I grow more cilantro than anything else and don't regret one second of time I've put into learning how to grow this delicious herb.
Light: Cilantro likes bright light, but dislikes intense, direct sunlight. The best option is morning sun in an east-facing window or a very bright sill that doesn't get too much direct sun.
Water: Keep the soil regularly moist, but not soaked. Good drainage is essential as cilantro has deep roots.
Temperature: On the cool side. Cilantro tends to bolt easily, especially in warmer weather. Keep your plants around 70˚F and you'll extend the harvest time. Once cilantro bolts, the flavor changes. Keeping the plant over 75˚ will greatly hasten flowering.
Soil: Airy, light, fast-draining soil with plenty of perlite or sharp sand mixed in to increase drainage.
Cilantro can be started as or purchased from a garden center. It's an annual and does not easily root from cuttings. Cilantro also readily produces seeds and self-seeds, so if you allow your plant to mature, you can harvest the seeds for next season.
Because it's a short-lived plant, if you want a steady supply of cilantro, sow seeds every few weeks to keep a fresh supply of young plants. If you're growing cilantro from your own seeds, prepare the seeds by gently crushing them to crack the husk, then soaking in water overnight and drying before planting. Prepared and dried seeds will last for months.
Cilantro is an annual that grows with a deep taproot. As a result, it dislikes repotting and will often bolt at the slightest provocation. It's best to repot your garden-center cilantro only once after bringing it home, then keep the plant in that container for the rest of its life. Seed-grown cilantro can transition from your seed-starting pot to its permanent home pot. Because cilantro is an annual, mature plants should never need repotting. A fully mature flowering cilantro plant can hit 24" tall, including flower stalks.
All cilantro is Coriandrum sativum. The plant is native to North Africa and warmer regions in Europe but has spread throughout the world. Leaves tend to be feathery and may resemble parsley. The flowers are small and white or pale pink. True cilantro is different than culantro (Eryngium foetidum), which has a stronger flavor.
Cilantro is best grown in a relatively cool, bright area with steady water and a deep container. Even then, the race is on to harvest leaves before the plant flowers and the flavor profile changes. To extend your cilantro harvest, regularly snip soft stems, rotating the plant as you harvest to encompass the whole plant. Although this is anecdotal, this type of harvesting seems to slow the flowering and extend the plant's useful life. Overall, expect your individual cilantro plant to live only for a few months before it flowers.