Cilantro is an annual, cool-season herb that grows best in temperatures between 50 and 85 degrees F. Choose a location that receives at least eight hours of full sun per day. In hotter climates, cilantro may perform best in light shade. Grow cilantro in a pot or in the ground, but don't expect it to stick around all summer.
Sow cilantro seeds directly in well-drained soil or in a pot filled with soilless potting mix (garden soil is too dense to use in containers). Place seeds 1/2 inch deep and about 1 inch apart, thinning them to about 6 inches apart before the plants start crowding each other.
When temperatures regularly stay hot, plants bolt, meaning they quickly flower, set seeds, and begin to die. In warm climates, spring and fall are the best seasons to plant cilantro. To keep a fresh source of cilantro, plant a few seeds every two to three weeks except in midsummer, when it's difficult to keep plants from bolting.
As with most herbs, cilantro can be difficult to grow indoors because even sunny windows don't provide as much sunlight as plants receive in outdoor shade. The plants may grow but may be spindly or leggy. Grow lights, which emit a larger light spectrum plants need, can provide a better chance of success.
Warm indoor temperatures also can cause this cool-season plant to begin flowering and setting seed faster than outdoors.
Sow seeds directly into a soilless potting mix. Place them 1/2 inch deep and about 1 inch apart. Harvest the leaves and seeds as you would from an outdoor planting.
If you grow cilantro, then you automatically grow coriander. The botanical name for cilantro is Coriandrum sativum. Cilantro becomes a coriander plant after it flowers and sets seeds. The dried seeds are called coriander for use in curries and other cooked dishes.
Cilantro's pretty, flat-top white flower clusters attract pollinators. Each flower turns into a round seedpod. When the seedpods turn brown, clip the stems and place everything into a paper bag. In a few days, the brown outside husk pops open, yielding two seeds per pod. If you wait too long to harvest the seedpods, don't fret. They'll drop onto the ground, where they're likely to self-sow.
Cilantro is not for everyone. According to studies, 4 to 14 percent of people perceive the flavor as soapy or unpleasant. This reaction has a lot to do with a person's genetics, including smell-receptor genes that detect the flavor of soap. Cilantro includes fat molecules called aldehyde chemicals, which are also present in soaps. Liking or not liking cilantro also may be a learned behavior.