Colorado’s unpredictable spring weather means cilantro should go in the ground after the danger of heavy snow has passed, typically in May. Finding the best time to plant cilantro in colorado depends on your local elevation and microclimate, but late spring is the safest bet for a steady harvest.
Cilantro loves cool weather but hates frost. In Colorado, that makes timing a bit tricky. You want the soil warm enough for seeds to germinate, but not so hot that the plant bolts—meaning it flowers and goes to seed—too quickly.
This guide walks you through exactly when and how to plant cilantro for success in Colorado’s unique growing conditions. We cover everything from soil temperature to fall planting tips.
Best Time To Plant Cilantro In Colorado
The ideal window for planting cilantro in Colorado is from mid-April to early June for spring crops, and again from late August to mid-September for a fall harvest. The exact dates shift based on where you live in the state.
Cilantro is a cool-season annual. It grows best when daytime temperatures stay between 50°F and 85°F. Once the heat of summer hits, it quickly sends up flower stalks and the leaves turn bitter.
Here is a simple breakdown by region:
- Denver and Front Range (5,000–6,000 ft elevation): Plant seeds outdoors in mid-to-late April, after the last frost. For fall, sow seeds in late August.
- Colorado Springs and lower elevations: Start a bit earlier, around early April for spring, and early September for fall.
- Mountain towns (above 7,000 ft): Wait until late May or early June for spring planting. Fall planting is risky because frost comes early; try late July for a quick crop.
- Western Slope (Grand Junction area): Plant in early April for spring, and early September for fall, since summers are hotter.
Always check your local frost dates. A light frost can kill young cilantro plants, but mature plants can survive a light freeze.
Soil Temperature Matters More Than Air Temperature
Cilantro seeds germinate best when the soil temperature is between 55°F and 68°F. If the soil is colder than 50°F, seeds may rot or take weeks to sprout.
Use a soil thermometer to check. Stick it two inches deep in the ground. If it reads 55°F or warmer, you are good to go.
In Colorado, soil warms up slowly in spring. Sunny, south-facing beds warm faster. Raised beds also heat up quicker than ground soil.
How To Test Your Soil Temperature
- Buy a simple soil thermometer at a garden center or online.
- Insert the probe two inches into the soil.
- Take the reading at midday, when the soil is warmest.
- Check three or four spots in your garden for consistency.
- Wait until the average reading is at least 55°F before planting.
Spring Planting: The Main Season
Spring is the most reliable time to grow cilantro in Colorado. The cool, moist conditions mimic its native Mediterranean climate.
For most of the state, the best time to plant cilantro in Colorado for spring is between mid-April and mid-May. This gives the plants about six to eight weeks of good growing weather before summer heat arrives.
If you plant too early, a late snow or hard freeze can kill the seedlings. If you plant too late, the cilantro will bolt quickly in June.
Step-By-Step Spring Planting Guide
- Prepare the soil: Choose a spot with full sun or light afternoon shade. Cilantro prefers well-drained soil rich in organic matter. Mix in compost or aged manure a week before planting.
- Sow seeds directly: Cilantro has a taproot and does not transplant well. Scatter seeds on the soil surface, then cover with about 1/4 inch of fine soil.
- Space properly: Thin seedlings to 4–6 inches apart once they have two sets of true leaves. This gives each plant room to grow.
- Water gently: Keep the soil evenly moist until seeds germinate, which takes 7–14 days. Use a fine spray to avoid washing seeds away.
- Mulch lightly: A thin layer of straw or shredded leaves helps keep soil cool and moist.
Succession Planting For A Continuous Harvest
Cilantro does not regrow well after cutting. Once you harvest the leaves, the plant usually bolts within a week or two. To have a steady supply, plant new seeds every two to three weeks.
Here is a sample schedule for the Front Range:
- First planting: April 20
- Second planting: May 5
- Third planting: May 20
- Fourth planting: June 5 (this one may bolt quickly, but you will get some leaves)
Stop spring planting by mid-June. After that, the heat makes it hard for new plants to establish.
Fall Planting: The Secret To Better Cilantro
Many Colorado gardeners overlook fall planting, but it often produces the best cilantro. The cooler temperatures and shorter days slow down bolting, giving you larger, tastier leaves for weeks.
The best time to plant cilantro in Colorado for fall is from late August to mid-September. You want the plants to mature before the first hard frost, which usually hits in October for most areas.
Fall Planting Tips
- Choose a spot that gets morning sun and afternoon shade to keep soil cool.
- Sow seeds directly in the ground or in containers.
- Water regularly, but do not overwater; fall rains often help.
- Cover plants with a row cover or frost blanket if a hard freeze is forecast.
- Harvest leaves until the plants die back from frost.
Fall-planted cilantro often survives light frosts and can be harvested into November in mild years.
Growing Cilantro In Containers
If your garden soil is heavy clay or you have limited space, grow cilantro in pots. Containers warm up faster in spring and can be moved to shade in summer.
Use a pot at least 8 inches deep with drainage holes. Fill with high-quality potting mix. Sow seeds 1/4 inch deep and water regularly.
Container-grown cilantro may need more frequent watering, especially in Colorado’s dry air. Check the soil daily and water when the top inch feels dry.
Best Varieties For Colorado
Some cilantro varieties are more bolt-resistant than others. These work well in Colorado’s climate:
- Calypso: Very slow to bolt, good for spring and fall.
- Santo: A standard variety with good flavor and decent bolt resistance.
- Leisure: Another slow-bolting option.
- Delfino: Has finer, fern-like leaves and is slower to flower.
Try a mix of varieties to see what works best in your garden.
Common Problems And Solutions
Colorado’s dry climate and temperature swings can cause issues. Here are the most common problems and how to fix them.
Bolting Too Early
If your cilantro flowers within a few weeks of planting, it is bolting. This happens when temperatures exceed 85°F or when days get long.
Solutions:
- Plant earlier in spring or later in fall.
- Provide afternoon shade.
- Use slow-bolt varieties.
- Keep soil consistently moist.
Poor Germination
Cilantro seeds need consistent moisture to sprout. If the soil dries out, germination fails.
Solutions:
- Water daily with a fine spray until seedlings appear.
- Cover the bed with a light layer of burlap or shade cloth to retain moisture.
- Soak seeds in water for 24 hours before planting to speed germination.
Yellow Leaves
Yellowing leaves often indicate overwatering or poor drainage. Cilantro does not like wet feet.
Solutions:
- Let the soil dry slightly between waterings.
- Improve drainage by adding compost or planting in raised beds.
- Check for pests like aphids, which can also cause yellowing.
Pests
Aphids and spider mites are the main pests for cilantro in Colorado. They thrive in dry conditions.
Solutions:
- Spray plants with a strong jet of water to knock off aphids.
- Use insecticidal soap for severe infestations.
- Encourage beneficial insects like ladybugs.
Harvesting Cilantro
You can start harvesting cilantro leaves when the plants are 4–6 inches tall, usually about 3–4 weeks after planting.
Cut the outer leaves at the base, leaving the inner leaves to grow. Do not cut more than one-third of the plant at a time.
Once flower stalks appear, the leaves lose flavor. Harvest all remaining leaves immediately, or let the plant go to seed for coriander.
How To Store Fresh Cilantro
Cilantro wilts quickly. To keep it fresh:
- Place stems in a glass of water, cover with a plastic bag, and refrigerate.
- Or wrap leaves in a damp paper towel and store in a sealed bag in the crisper drawer.
- Use within 5–7 days for best flavor.
You can also freeze cilantro. Chop it, pack into ice cube trays with water or olive oil, and freeze. Use the cubes in soups and sauces.
Frequently Asked Questions
Can I Plant Cilantro In Colorado In July?
July is too hot for cilantro in most of Colorado. The plants will bolt quickly. If you want a summer crop, try growing it in a shaded spot or indoors near a cool window.
How Late Can I Plant Cilantro In Colorado For Fall?
For most areas, plant by mid-September. In warmer parts like Grand Junction, you can plant until early October. In mountain towns, aim for late August.
Does Cilantro Need Full Sun In Colorado?
Cilantro grows best in full sun during spring and fall. In summer, afternoon shade helps prevent bolting. In Colorado’s intense sun, some shade is often beneficial.
Can I Grow Cilantro Indoors In Colorado?
Yes. Grow cilantro on a sunny windowsill or under grow lights. Use a pot with drainage and keep the soil moist. Indoor cilantro may not grow as large as outdoor plants, but it works for small harvests.
What Is The Best Time To Plant Cilantro In Colorado Springs?
For Colorado Springs, plant seeds outdoors in early to mid-May for spring. For fall, sow seeds in late August. The city sits at about 6,000 feet, so spring comes a bit later than in Denver.
Final Tips For Success
Cilantro is one of the easiest herbs to grow in Colorado if you get the timing right. Focus on spring and fall planting, keep the soil moist, and harvest often.
Remember that the best time to plant cilantro in colorado varies by elevation. Check your local frost dates and soil temperature before planting.
With a little planning, you can enjoy fresh cilantro from your garden from May through November. That is a long season for such a finicky herb.
Start with a small patch this year. Experiment with different planting dates and varieties. You will quickly learn what works best in your specific garden microclimate.
Happy growing, and enjoy your homegrown cilantro on tacos, salsas, and curries all season long.