Coriander seeds come from the coriander plant, which is also known as cilantro or Chinese parsley. The seeds are used as a spice in cooking, while the leaves (cilantro) are also commonly used in various cuisines.

To grow coriander:

1. Choose the Right Time: Coriander grows best in cooler weather, so it’s ideal to plant it in spring or fall. In hotter climates, it can be grown during cooler months or in partial shade to prevent the plant from bolting (going to seed) too quickly.
2. Select a Location: Find a spot that receives partial shade to full sun. Ensure the soil is well-draining and fertile.
3. Planting Seeds: You can either directly sow seeds into the ground or start them indoors in pots. If sowing outdoors, scatter the seeds thinly and cover them lightly with soil. Space them about 6 to 8 inches apart.
4. Soil Requirements: Coriander prefers a slightly acidic to neutral soil pH (around 6.2 to 6.8). Ensure the soil is rich in organic matter.
5. Watering: Keep the soil consistently moist but not waterlogged. Water regularly, especially during dry periods.
6. Thinning: If you’ve planted seeds densely, thin the seedlings when they’re a few inches tall, leaving about 6 to 8 inches between plants.
7. Fertilization: You can apply a balanced fertilizer or compost to the soil a few times during the growing season to encourage healthy growth.
8. Harvesting: Coriander leaves can be harvested once the plant reaches about 6 inches in height. To collect coriander seeds, allow the plant to bolt and go to seed. The seeds will form after the flowers fade and turn brown. Cut the seed heads when they begin to turn brown and dry, then hang them upside down in a paper bag to catch the seeds as they fall.
9. Storage: Once harvested, store the coriander seeds in an airtight container away from light and heat. They’ll retain their flavor for several months.

Remember, coriander plants have a relatively short lifespan and tend to bolt in hot weather, so planting successive crops every few weeks can provide a continuous harvest throughout the growing season.