Growing Coriander: A Simple Step-by-Step Garden Guide

Growing Coriander: A Simple Step-by-Step Garden Guide

I grow coriander for two reasons, bright leaves fast and fragrant seeds later. Same plant, two moods.

Growing Coriander rewards steady rhythm, cool soil, and timely cuts. Heat and long days trigger flowering, called bolting.

"Sow little and often for a steady supply." RHS advice that finally cured my feast-or-famine cilantro habit.

Leaves taste best in cool weather, 50 to 70 F (10 to 21 C). Seed sets well as temperatures rise, provided water holds steady.

Step-by-step: from seed to salsa, then spice

1. Pick the spot. Full sun in spring and fall, light afternoon shade in summer.

   Use well-drained loam with pH 6.2 to 6.8, or a high-quality potting mix with compost.

2. Choose seed by goal. For leaves, pick slow-bolting types like Santo, Calypso, Leisure, Caribe.

   For seed, any standard coriander does fine, though Moroccan strains dry fast and shatter cleanly.

3. Prep the seed. Coriander fruits are two seeds fused, so I gently roll them under a jar to split.

   Soak 8 to 12 hours to speed germination, then sow right away.

4. Sow. Direct sow, 0.25 to 0.5 in deep (6 to 12 mm), rows 12 in apart (30 cm).

   Space seeds 1 in (2.5 cm), then thin to 4 to 6 in (10 to 15 cm) once they have true leaves.

5. Water. Keep soil evenly moist during germination, 7 to 21 days depending on temperature.

   Target about 1 in (25 mm) of water per week, more in heat or containers.

6. Feed and mulch. I side-dress with finished compost or a balanced organic 4-4-4 at half rate.

   Mulch lightly once plants reach 3 in (7.5 cm) to steady moisture and cool the crown.

7. Manage heat. Above 75 F (24 C), use 30 percent shade cloth after noon.

   Shade slows bolting and keeps leaves tender.

8. Harvest leaves. Cut outer stems first at 4 to 6 in tall (10 to 15 cm), leave the center to regrow.

   Never scalp the plant, take up to one third each pick for longer production.

9. Let some bolt for seed. Once umbels bloom, I stop fertilizing and keep watering.

   Bees mob the flowers, and beneficial wasps show up for the nectar.

10. Dry and save seed. When umbels turn straw-tan, bag heads and clip to avoid shatter.

    Dry fully, rub free, then store airtight; label the harvest month to track vigor.

Timing by climate

• Cool-summer or coastal: sow spring through early summer, then again late summer for fall.
• Hot-summer inland: sow late winter to spring, pause in peak heat, sow again late summer to fall.
• Mild winters: overwinter plantings thrive, especially with frost cloth on cold snaps near 32 F (0 C).

Leaves in 30 to 45 days, green seed in 70 to 90, dry seed in 90 to 120. Figures widely reported by RHS and U.S. university extensions.

Indoor and container tactics

Coriander hates root disturbance, so sow in final pots or 4 in (10 cm) deep modules. I use 8 to 10 in deep containers (20 to 25 cm) for steady moisture.

Under lights, run 12 to 14 hours at 6500 K, keep temps 60 to 70 F (16 to 21 C). Air movement prevents damping-off.

• Soilless mix: peat or coco, compost, perlite, a dash of organic fertilizer pre-mixed.
• Bottom watering prevents splash and fungal issues.
• Rotate containers weekly for upright stems and even leaf density.

Water and nutrition, without the drama

Uneven moisture triggers stress, which pushes bolting. A simple drip line or clay olla in beds smooths the curve.

For steady leaves, feed lightly every 2 to 3 weeks with fish or seaweed at half strength. Heavy nitrogen gives bulk but can mute flavor.

Pest and disease playbook

• Aphids: blast with water, then follow with insecticidal soap. Flowering coriander invites hoverflies that clean house.
• Leaf miners: pinch off mined leaves, use row cover early if they are yearly guests.
• Damping-off: sow thinner, improve airflow, and avoid overwatering seedlings.
• Powdery mildew: space plants, water at soil level, and pick older leaves first.

Common mistakes and quick fixes

• Transplanting big starts: the taproot sulks, so direct sow or transplant very young plugs.
• Cutting the whole crown: harvest outer stems to keep the plant productive.
• Letting pots dry between soakings: mulch and deeper containers prevent stress spikes.
• Summer sun all day: give afternoon shade and pick heat-tolerant varieties.

Top coriander varieties worth growing

• Santo: reliable slow-bolter for spring successions.
• Calypso: very slow to bolt under long days, broad leaves.
• Leisure: classic flavor, quick leaf mass, great for cut-and-come-again.
• Caribe: handles heat better than most, sturdy stems for bunching.
• Long Standing: later to bolt, good for home gardens.
• Confetti: frilly leaves with mild flavor, decorative in bowls.
• Moroccan-type coriander: generous seed set and fast dry-down for spice.

Shopping checklist I actually use

• Fresh seed from reputable suppliers, packed for the current season.
• 30 percent shade cloth and spring clamps for quick summer rigs.
• 8 to 10 in deep pots with large drainage holes, plus saucers for indoor runs.
• Quality potting mix plus perlite, or a raised bed mix that drains fast.
• Drip kit or simple soaker hose, a timer, and a watering rose for seedlings.
• Bypass snips for clean cuts, brown paper bags for drying umbels.
• Soil thermometer, pH meter or strips, and a small fan for indoor airflow.

Harvest, storage, and flavor

I cut early morning and chill unwashed stems in a jar of water, bag loosely, then refrigerate. Leaves keep 5 to 7 days like cut flowers.

For longer storage, chop and freeze in olive oil cubes. Dry seeds low and slow, then toast lightly to unlock citrus, cedar, and a hint of white pepper.

Coriander loves carrots, beets, and grilled fish. It links the garden to the skillet with a short, fragrant bridge.

Advanced: hydro coriander that actually performs

• EC 1.2 to 1.6 mS/cm, pH 6.0 to 6.5, cooler solution temps for tight plants.
• 12 to 14 hours of light, keep canopy 8 to 12 in (20 to 30 cm) from LEDs.
• Dense sow in rafts for baby-leaf harvest at 28 to 35 days.

FAQ, straight and fast

• Why did it bolt overnight? Heat spikes, dry pots, or long day length; pick slow-bolting types and add afternoon shade.
• Why does it taste soapy? About 10 to 14 percent of people carry an olfactory receptor variant that perceives aldehydes as soap, reported by genetic studies including 23andMe research.
• Can I grow grocery store coriander seed? Sometimes, though it may be heat-treated; germination runs lower and uneven.
• Can I cut to the ground and regrow? It regrows weakly; better to harvest outer stems repeatedly or resow every 2 to 3 weeks.
• Leaf vs seed timing? I sow for leaves early, let late plantings flower for seed as summer arrives.

Numbers that help

• Optimal germination: 55 to 70 F (13 to 21 C); below 50 F (10 C) is slow, above 75 F (24 C) invites bolting.
• Spacing: 4 to 6 in plants, 12 in rows (10 to 15 cm, 30 cm rows).
• Soil pH: 6.2 to 6.8 with steady moisture, never waterlogged.

Field notes and cross-crop tips

Like lettuce, coriander treats heat as a timer, so shade buys time and flavor. Like dill, flowers pull hoverflies and lacewings that patrol aphids on peppers and brassicas.

I pair successions with scallions and radishes to keep beds moving. The roots leave soil crumbly for the next sowing.

Selected sources and quotes

• Royal Horticultural Society: cultural notes on coriander, including sowing intervals and bolt management.
• University extensions, including UC ANR, Penn State, and Minnesota: growth temps, spacing, and harvest windows.
• USDA and FAO references: cool-season annual behavior and general production guidance.
• 23andMe research blog on cilantro perception genetics: prevalence of the soapy-taste variant.

"Cilantro prefers cool growing conditions and bolts quickly under heat," a steady refrain across U.S. extension guides that matches what the soil keeps telling me.

Growing coriander isn’t rocket science—it’s about keeping things simple and paying attention. Sow fresh seeds. Keep the soil moist, but don’t drown them. Give their roots room and their leaves a little afternoon shade. Before you know it, you’ll have a patch of bright, aromatic greens and the seeds to keep the cycle going. The real satisfaction comes from that first handful, snipped onto a homemade curry or salad—fresh, peppery, absolutely yours. Hungry for more flavor in your garden? You might enjoy trying perilla or a twist with lovage. But for now, celebrate the honest joy of growing coriander, one harvest at a time.