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

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

I grow coriander for both lush leaves and fragrant seed, and I treat each like a different crop. The plant has opinions, and it rewards gardeners who read the signals.

Know your plant: cilantro vs. coriander

Coriander is Coriandrum sativum. In North America, the leaves are called cilantro and the dried seeds are coriander.

I harvest leaves young for salsa and pakoras. I let later sowings run to seed for spice jars and pickled green seeds.

Site and season

Coriander prefers cool, bright weather. I get the best leaves in spring and fall at 50 to 75 F, 10 to 24 C.

Heat above 85 F, 29 C, and long days trigger bolting, which means flower stalks and fewer tender leaves. Shade cloth and steady moisture delay it.

RHS advises a sunny, well-drained site with regular water, and notes that hot, dry spells cause rapid bolting.

Soil prep

Loamy, well-drained soil with a pH of 6.2 to 6.8 suits coriander. I mix in finished compost and a light organic pre-plant feed at 3-4-4 or similar.

Heavy nitrogen gives floppy foliage and weaker flavor. Keep it modest and steady.

Seed prep that speeds germination

Coriander seed is a schizocarp with two seeds fused. I gently crack the hulls with a rolling pin, then soak 8 to 12 hours.

That trick shortens germination from two weeks to about one. Warm soil helps too.

Sowing method

1. Direct sow 0.25 to 0.5 inch deep, 6 to 12 mm. I space rows 8 inches, 20 cm, for leaf harvest, wider for seed harvest.
2. Thin to 2 to 4 inches, 5 to 10 cm, for leafy bunches. Give 6 inches, 15 cm, if you want big umbels for seed.
3. Succession sow every 2 to 3 weeks. Small, steady sowings beat one big planting.

Extension trials report germination in 7 to 14 days at 55 to 68 F, 13 to 20 C, and seed maturity in roughly 90 to 120 days.

Containers and indoor setups

I use a pot at least 8 inches deep, 20 cm, with a high quality mix and sharp drainage. A 2 gallon, 7.5 liter, container grows a generous clump.

Give 6 hours of light minimum, with a cool room and a fan for airflow. Overheated kitchens turn coriander cranky.

Watering rhythm

Keep the top inch, 2.5 cm, evenly moist. Dry spells spike bitterness and prompt bolting.

I water in the morning at soil level. Mulch lightly with straw to stabilize moisture.

Feeding schedule

Side dress with compost at 3 to 4 weeks. A seaweed or fish emulsion at half strength every 10 to 14 days keeps growth steady.

Avoid heavy feeding late. It pushes soft growth that wilts in heat.

Leaf harvest technique

Cut outer stems first and leave the crown. I harvest at 30 to 40 days for peak flavor.

Never scalp the plant. Leave at least one third of the foliage each pick to keep it pushing new leaves.

Seed harvest and curing

Once umbels brown, I cut whole heads and bag them paper-dry indoors. Good airflow is key.

Seeds are ready when they roll free and shatter cleanly. I finish-dry to 9 percent moisture by feel, crisp and aromatic.

Flavor trick: green seeds

Pick immature green seeds and quick-pickle them with vinegar, salt, and a hint of sugar. The pop of citrus pine is fierce.

I stash jars next to capers. They make plain eggs sing.

Bolt control

Heat and daylength drive flowering. I plant on the east side of taller crops for dappled afternoon shade.

Use 30 percent shade cloth during hot spells. Water deeply before heat spikes to buffer stress.

Pests and problems

• Aphids: blast with water, then follow with insecticidal soap. Lady beetles and hoverflies help if you leave some fennel or alyssum nearby.
• Leafminers: remove mined leaves quickly. Floating row cover at sowing keeps adults off.
• Damping-off: sterilize trays, avoid overwatering, and increase airflow. Sow slightly shallower in cool soil.
• Powdery mildew: rare in my beds. Wider spacing and morning water prevent it.

UC publications emphasize consistent moisture and spacing as the simplest way to reduce coriander stress and pest pressure.

Companions and rotation

Coriander attracts lacewings, syrphid flies, and tiny parasitic wasps once it blooms. I tuck it near brassicas and tomatoes for free pest patrol.

Avoid planting next to fennel. The chemistry gets weird and growth suffers.

Varieties I trust

• Santo: slow to bolt and reliable in spring. My default for leaves.
• Caribe: handles early heat. Shorter, bushy habit.
• Calypso: very slow to bolt, high leaf yield. Good for containers.
• Leisure: classic market type with balanced flavor. Predictable germination.
• Jantar or Moroccan: bred for seed production. Big umbels and high oil content.

Buying guide and quick cost check

Choose fresh seed from the current season. Old coriander seed gets stingy.

Packets run about 2 to 5 USD or 2 to 5 EUR. For restaurants or market growers, a quarter pound bulk bag pays off fast.

Skip leggy transplants. Direct sow or buy very young starts with short, stocky stems and no yellowing.

Kitchen grade quality, farm habits

I cut early in the day, dunk quickly in cold water, and spin dry. Chill at 34 to 38 F, 1 to 3 C, in a perforated bag.

Leaves hold 5 to 7 days like this. Seed stores a year in glass away from light.

Common questions, straight answers

• Can I grow coriander year round indoors. Yes with cool temps, bright light, and frequent sowings every three weeks.
• Does pinching prevent bolting. No, pinching delays a little but heat and daylength still win.
• Can I cut all at once for bunches. Yes, but plant more often to keep supply steady.

My field notes

Best spring sowing window for me lands when soil hits 55 F, 13 C, at dawn. Anything colder slows germ and invites rot.

In summer, I aim for morning sun and shade after 1 p.m. The difference in leaf tenderness is noticeable.

Science in simple words

Bolting is driven by photoperiod and heat stress hormones. Long days whisper grow up, and the plant obeys.

Cool roots and steady moisture keep growth vegetative. That is the whole game for leaves.

Flavor and oil content

For seed spice, slight water stress near maturity concentrates essential oils. I learned this from a spice grower who measured it with a small still.

For leaves, avoid stress. Bitter notes creep in fast.

Safety and allergens

Coriander can cross-react with celery and carrot family allergies. Wear gloves if you react to Apiaceae pollen.

Flowers are a pollinator magnet. I let a patch bloom for the bees every season.

Simple calendar

• Germination: 7 to 14 days at 55 to 68 F, 13 to 20 C.
• First leaf harvest: 30 to 40 days after sowing.
• Green seed: 60 to 75 days. Dry seed: 90 to 120 days.

Toolkit I actually use

• Hori hori for shallow furrows and quick thinning.
• 30 percent shade cloth and spring clamps for heat snaps.
• Fine rose watering can for seedlings, drip line for mature beds.
• Paper bags, mesh screen, and a big bowl for seed drying and winnowing.

From the literature

RHS guides frame coriander as a cool-season annual that resents root disturbance and prefers direct sowing. I agree based on repeated side-by-side trials.

Penn State and UC extension bulletins echo the same themes on temperature, spacing, and quick, repeated sowings. Those simple habits deliver consistent harvests.

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.