If you’re wondering when to plant lavender in Colorado, timing is everything for success. The state’s unique climate, with its intense sun and tricky frosts, makes picking the best planting times for lavender a crucial first step.
This guide will walk you through the ideal windows for planting, from spring to fall, and give you the tips you need to grow fragrant, resilient lavender plants in your Colorado garden.
When to Plant Lavender in Colorado – Best planting times for
For most of Colorado, the prime time to plant lavender is in the late spring, after the danger of the last frost has passed. This typically falls from mid-May to early June. The soil has warmed up by then, which lavender roots prefer.
You can also plant in early fall, aiming for late August to mid-September. This gives the plant enough time to establish its roots before the ground freezes. Fall planting is often very succesful because the cooler air reduces transplant shock.
Why Timing Matters So Much in Colorado
Colorado’s climate is a mix of challenges. Lavender thrives in hot, dry, rocky conditions similar to its Mediterranean home. But our state adds extra variables.
- Unpredictable Spring Frosts: A late frost can damage or kill tender new growth. Planting too early is a common mistake.
- Clay and Heavy Soil: Colorado soil often drains poorly. Planting in warmer, drier weather helps roots establish without sitting in cold, wet earth.
- High Altitude Sun: The intense UV can scorch young plants. A later spring planting allows for stronger leaf development before the hottest sun arrives.
Spring Planting: The Most Common Window
Spring is the recommended season, especially for beginners. Here’s how to do it right.
- Watch the Weather, Not Just the Calendar: Don’t plant on a specific date. Wait until nighttime temperatures reliably stay above 50°F.
- Harden Off Your Plants: If you bought lavender from a greenhouse, acclimate it to outdoor sun and wind over 7-10 days.
- Choose a Sunny Spot: Select a location that gets at least 6-8 hours of direct sun daily. More is better.
- Amend the Soil: Dig a hole twice as wide as the root ball. Mix the native soil with plenty of gravel, sand, or crushed rock to ensure sharp drainage.
Fall Planting: A Secret for Stronger Roots
Fall planting leverages the warm soil and cool air. The plant focuses energy on root growth instead of top growth. This can lead to a more robust plant the following summer.
- Deadline is Key: Get your lavender in the ground at least 6-8 weeks before your area’s first average hard frost. This gives roots time to anchor.
- Watering is Different: Water thoroughly at planting. After that, rely mostly on natural precipitation, as overwatering in cooler temps is a risk.
- Winter Protection: After the ground freezes, apply a thin layer of small gravel or pea stone as mulch. Avoid moisture-retaining mulch like bark.
Choosing the Right Lavender for Colorado
Not all lavenders are equaly suited for our state. The hardiest varieties are your best bet.
Top Recommended Varieties
- English Lavender (Lavandula angustifolia): The most cold-hardy. Look for ‘Munstead’, ‘Hidcote’, or ‘Phenomenal’.
- Lavandin (Lavandula x intermedia): A hybrid known for its oil and size. ‘Grosso’ and ‘Provence’ do well here with good drainage.
It’s generally best to avoid more tender types like Spanish or French lavender, as they rarely survive a Colorado winter.
Step-by-Step Planting Guide
- Test Your Drainage: Dig a test hole 12 inches deep and fill it with water. If it drains in less than 15 minutes, you’re good. If not, you must amend heavily or consider a raised bed.
- Prepare the Site: Remove all weeds and grass. Loosen the soil deeply.
- Create the Perfect Mix: For each plant, mix 1 part native soil with 1 part coarse sand or fine gravel. A handful of lime can help sweeten acidic soil.
- Plant High: Set the crown of the plant (where stem meets roots) slightly above the soil line. This prevents rot.
- Water Wisely: Water deeply immediately after planting. Then, let the soil dry out completely between waterings.
- Skip the Fertilizer: Lavender prefers poor soil. Fertilizer can lead to weak, leggy growth and fewer flowers.
Common Mistakes to Avoid
- Overwatering: This is the fastest way to kill lavender. Its roots are prone to rot in damp soil.
- Using Organic Mulch: Bark or wood chips hold moisture against the stems. Use inorganic mulch like rock instead.
- Planting in Shade: Without full sun, your plant will become leggy and produce few flowers.
- Not Pruning: Start pruning in year two to prevent a woody, sprawling center. Prune lightly after flowering and again in early spring.
FAQ: Your Lavender Questions Answered
Can I plant lavender in Colorado in the summer?
It’s not ideal. The heat stress can be too much for a young plant trying to establish roots. If you must, plant on a cloudy day and be vigilant about watering (but still allowing soil to dry).
What is the best month to plant lavender in Colorado?
For spring planting, target June. For fall planting, target early September. Adjust based on your specific altitude and microclimate.
How do I protect my lavender in winter?
The key is dry roots. Ensure your soil drains perfectly. A gravel mulch helps. Avoid pruning in late fall, as the foliage provides some insulation. For extra protection, a burlap screen can shield plants from harsh winds.
Can I grow lavender from seed in Colorado?
It’s very challenging and slow. Seeds require specific stratification (cold treatment) and germination is uneven. Starting with small nursery plants is the most reliable and faster method for our climate.
Why did my lavender die over the winter?
The most likely culpret is wet soil, not the cold itself. Lavender can handle cold, but not cold wet feet. Improving drainage before replanting is essential.
By following these timing and planting guidelines, you can enjoy the beauty and fragrance of lavender in your Colorado landscape for years to come. Its drought tolerance and appeal to pollinators make it a perfect choice for a sustainable, low-maintenance garden.