Arizona’s intense heat limits cilantro to fall and winter planting, with seeds going in from September through January. The best time to plant cilantro in arizona is during these cooler months to avoid the plant bolting (going to seed) too quickly.
Cilantro loves cool weather. In Arizona’s desert climate, that means you have a narrow window. Plant too early, and the heat will kill it. Plant too late, and it won’t mature before summer arrives.
This guide walks you through exactly when and how to plant cilantro in Arizona. You’ll get specific dates for Phoenix, Tucson, and Flagstaff. Plus tips for containers, soil, and watering.
Best Time To Plant Cilantro In Arizona
The best time to plant cilantro in arizona is from mid-September through January. This gives the plant cool nights and mild days. Cilantro grows best when temperatures stay between 50°F and 85°F.
In lower elevations like Phoenix and Tucson, September to November is prime. In higher elevations like Flagstaff, you can plant from April to August.
Here’s a breakdown by region:
- Phoenix area (Zone 9b-10a): September 15 to January 15
- Tucson area (Zone 9a-9b): September 20 to January 10
- Flagstaff area (Zone 6a-7a): April 1 to August 15
- Prescott area (Zone 7b-8a): March 15 to June 1, then again September 1 to November 1
If you plant in September, you’ll harvest leaves by October. A second planting in November gives you fresh cilantro through February.
Why Timing Matters So Much In Arizona
Cilantro is a cool-season annual. When temperatures rise above 85°F, it bolts. That means it sends up a flower stalk and stops producing leaves.
In Arizona, summer heat arrives fast. By April, daytime temps often hit 90°F. So you need to harvest before then.
Planting in fall gives you 4-5 months of growth. That’s plenty of time for multiple harvests.
What Happens If You Plant Too Late
Planting in February or March might work, but it’s risky. The plant will grow quickly and bolt as soon as warm weather hits.
You’ll get maybe 3-4 weeks of leaves instead of 3-4 months. The leaves also taste more bitter when the plant is stressed by heat.
Better to plant early and enjoy a long season.
Step-By-Step Guide To Planting Cilantro In Arizona
Step 1: Choose The Right Variety
Not all cilantro varieties handle heat the same. For Arizona, pick slow-bolting types.
- Calypso: Very slow to bolt. Great for fall planting.
- Santo: Standard variety. Works well in cooler months.
- Leisure: Another slow-bolting option.
- Long Standing: Lives up to its name in mild weather.
Avoid “Coriander” types meant for seed production. They bolt faster.
Step 2: Prepare The Soil
Cilantro needs well-draining soil. In Arizona, our native soil is often clay or caliche. That holds too much water.
Mix in compost or aged manure. Aim for a loose, sandy loam. A 50/50 mix of native soil and compost works well.
Soil pH should be between 6.2 and 6.8. Test your soil if you can. Most Arizona soil is alkaline, so add sulfur if needed.
Step 3: Plant The Seeds
Cilantro seeds are actually two seeds in one husk. Plant them whole. Don’t try to separate them.
- Soak seeds in water for 24 hours before planting. This speeds germination.
- Sow seeds 1/4 inch deep.
- Space seeds 2 inches apart in rows 6 inches apart.
- Cover lightly with soil.
- Water gently with a fine spray.
Seeds germinate in 7-14 days. Keep soil moist but not soggy.
Step 4: Thin The Seedlings
Once seedlings have 2-3 true leaves, thin them. Leave 4-6 inches between plants.
Thinning is important. Crowded plants compete for water and nutrients. They also bolt faster.
You can eat the thinned seedlings. They taste like mild cilantro.
Step 5: Water Correctly
Cilantro needs consistent moisture. In Arizona’s dry air, that means watering every 2-3 days in fall.
In winter, water less often. Every 4-5 days is usually enough.
Water at the base of the plant. Avoid wetting the leaves. Wet leaves can lead to fungal diseases.
Use drip irrigation or a soaker hose. This saves water and keeps leaves dry.
Step 6: Fertilize Lightly
Cilantro doesn’t need much fertilizer. Too much nitrogen makes leaves taste bland.
Apply a balanced 10-10-10 fertilizer at planting time. Then side-dress with compost once a month.
If leaves look pale, add a liquid fish emulsion. Follow label directions.
Growing Cilantro In Containers In Arizona
Containers are a great option for Arizona gardeners. You can move them to shade when it gets hot.
Choose a pot at least 8 inches deep. Cilantro has a taproot that needs room.
Use a high-quality potting mix. Add perlite for drainage.
Place containers in morning sun and afternoon shade. In winter, full sun is fine.
Water containers more often than garden beds. Every 1-2 days in fall.
Best Container Varieties
Compact varieties work best in pots.
- Calypso stays small and bushy.
- Santo grows upright but not too tall.
- Delfino has fine, fern-like leaves.
Avoid tall varieties like ‘Long Standing’ in small pots.
Harvesting Cilantro In Arizona
Start harvesting when plants are 4-6 inches tall. Pick outer leaves first. Leave the inner leaves to keep growing.
Never cut more than one-third of the plant at once. This stresses it and can trigger bolting.
Harvest in the morning when leaves are crisp. Rinse and use immediately.
You can store cilantro in the fridge for up to a week. Wrap it in a damp paper towel and put it in a plastic bag.
How To Extend Your Harvest
To keep cilantro producing longer:
- Pinch off flower buds as soon as they appear.
- Keep soil consistently moist.
- Provide afternoon shade in late winter.
- Plant in succession every 3-4 weeks.
Succession planting is key. Plant a new batch every month from September to January. That way, you always have fresh cilantro.
Common Problems Growing Cilantro In Arizona
Bolting
This is the biggest problem. Cilantro bolts when stressed by heat, drought, or overcrowding.
Signs of bolting: Leaves become thin and lacy. A tall stalk shoots up. Flowers appear.
Once bolted, leaves turn bitter. You can still eat them, but they’re not as good.
To delay bolting, keep plants cool and well-watered. Plant in partial shade if possible.
Pests
Aphids are the main pest. They suck sap from leaves and can spread disease.
Spray aphids off with a strong stream of water. Or use insecticidal soap.
Other pests: Spider mites in dry weather. Slugs and snails in damp areas.
Use diatomaceous earth around plants for slugs.
Diseases
Powdery mildew can appear in humid conditions. It looks like white powder on leaves.
Prevent by watering at the base. Space plants for good air flow.
If mildew appears, remove affected leaves. Spray with a baking soda solution (1 teaspoon per quart of water).
Best Companion Plants For Cilantro In Arizona
Cilantro grows well with many vegetables. It attracts beneficial insects like ladybugs and hoverflies.
Good companions:
- Tomatoes (plant in spring, not same season)
- Peppers
- Spinach
- Lettuce
- Radishes
- Dill
Avoid planting near fennel. Fennel can cross-pollinate and ruin the flavor.
Using Cilantro In Arizona Cooking
Cilantro is essential in Mexican and Southwestern cuisine. Use it fresh in salsas, tacos, and salads.
Add it at the end of cooking. Heat destroys the flavor.
You can also freeze cilantro. Chop it and put it in ice cube trays with water. Use the cubes in soups and stews.
Dried cilantro loses most of its flavor. Stick with fresh or frozen.
Frequently Asked Questions
What Is The Best Time To Plant Cilantro In Arizona For A Fall Harvest?
Plant seeds from mid-September to mid-October. You’ll harvest leaves from October through December. This is the most reliable window.
Can I Plant Cilantro In Arizona In The Spring?
Yes, but it’s risky. Plant in February or March. Harvest by April before heat arrives. Use slow-bolting varieties and provide shade.
How Often Should I Water Cilantro In Arizona?
Water every 2-3 days in fall. Every 4-5 days in winter. Check soil moisture by sticking your finger an inch deep. Water if dry.
Does Cilantro Grow Back Every Year In Arizona?
No, cilantro is an annual. It completes its life cycle in one season. But it self-seeds easily. Let some plants go to flower, and they’ll drop seeds for next year.
What Temperature Is Too Hot For Cilantro In Arizona?
Temperatures above 85°F cause bolting. Above 95°F, the plant will likely die. Move containers to shade or use shade cloth.
Final Tips For Success
Start with fresh seeds each year. Cilantro seeds lose viability quickly.
Soak seeds overnight before planting. This speeds germination by several days.
Plant in partial shade if you have it. Morning sun and afternoon shade is ideal.
Mulch around plants to keep soil cool and moist. Use straw or wood chips.
Harvest often. Frequent picking encourages more leaf growth.
If your cilantro bolts, let it flower. The flowers attract pollinators. Then collect the seeds (coriander) for cooking or planting.
With the right timing, you can enjoy fresh cilantro for months. Arizona’s cool season is perfect for this herb. Just plant between September and January, and you’ll have a steady supply.
Remember, the best time to plant cilantro in arizona is when the weather is cool. Stick to fall and winter. Your plants will thank you with abundant, flavorful leaves.