Cilantro, a popular annual herb, offers gardeners a dual harvest: its flavorful leaves and its seeds, known as coriander. While many gardeners focus on the fresh foliage, allowing the plant to complete its life cycle yields seeds for culinary use or for planting the following season. Saving these seeds requires specific steps to ensure they remain viable. This guide details the process for successfully harvesting and preserving cilantro seeds for future planting.
Preparing the Cilantro Plant for Seeding
Producing viable seeds requires allowing the cilantro plant to transition naturally from its leafy growth stage to reproduction. This transition, involving sending up a central stalk and flowering, is called bolting. Bolting is triggered by rising ambient temperatures above 70°F and the long daylight hours of late spring and early summer.
Once the plant bolts, it focuses its energy on flowering rather than producing the broad, soft leaves favored for fresh consumption. The remaining leaves become more feathery and the flavor may become less desirable. For seed saving, the plant must be left in the garden past its prime leaf-harvesting period to encourage the full development of the seeds.
Identifying and Harvesting Mature Seed Heads
After the delicate white or pink flowers fade, they are replaced by small, round seed pods, or umbels, that initially appear bright green. The timing of the harvest is dictated by the color and texture of these seed heads, not the calendar alone. Immature green seeds will not germinate reliably.
The seeds are ready for collection when they change color from green to a light tan or pale brown, indicating they have dried out on the stem. The plant’s stalk will also appear dry and brittle. To maximize seed viability, harvest when approximately 50 to 75 percent of the seeds on the plant show this color transformation.
The most efficient harvesting technique involves cutting the entire seed-bearing stalk rather than attempting to pick individual seeds. Use sharp shears to snip the stems, leaving about six inches of stem attached to the seed head. Harvesting in the early morning, after the dew has evaporated but before midday heat, minimizes the loss of dry seeds.
Cleaning, Curing, and Drying the Seeds
After the stalks are cut, the seeds require curing to ensure complete dryness before long-term storage. This involves tying the cut stems together and hanging them upside down in a cool, dark, and well-ventilated location. The drying area should maintain a temperature between 70–80°F to dry the material without degrading the essential oils within the seeds.
Many seeds will naturally drop off the stems into a container or paper bag placed beneath the suspended stalks during the one to two-week curing period. Once the stems are fully dry, the remaining seeds can be removed by gently rubbing the seed heads between your hands over a tray. This process separates the round seeds from the dried stem material, known as chaff.
A final cleaning step removes remaining debris. Because cilantro seeds are round, they are easily separated from the flat chaff by rolling them across a flat surface with a slight lip. This allows the heavier seeds to collect while the lighter chaff remains behind. After cleaning, the seeds must be spread in a single layer on a mesh screen or paper towel for a final drying period of a few days. To confirm the seeds are completely dry, crush one: a properly dried seed will crumble cleanly rather than feeling soft or moist.
Storage Methods and Seed Viability
Proper storage is crucial for maintaining the germination potential of the seeds for future planting seasons. The ideal environment for cilantro seeds is cool, dark, and dry, as exposure to light, heat, or humidity can quickly degrade their viability. Airtight containers, such as glass jars or sealed plastic bags, are best for protecting the seeds from moisture fluctuations.
For planting purposes, the seeds can be placed inside paper envelopes or small cloth bags before being sealed in the airtight container. This double-layer method helps regulate internal moisture. When stored under optimal conditions, cilantro seeds can remain viable for planting for approximately one to three years.
The seeds can be stored below 70°F in a dark location, such as a pantry or refrigerator, to extend their longevity. It is helpful to label the container with the date of harvest and the seed variety to track viability and ensure the freshest seeds are used for the next season’s planting.