When to Plant Lavender in Sweetwater County, WY
June in Sweetwater County, Wyoming — your action list
Your Sweetwater County, Wyoming garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.
-
Harden off and plant lavender
Frost risk is low now in Sweetwater County, Wyoming. If you've been covering beds overnight, you can stop.
Lavender (Lavandula angustifolia) is a fragrant Mediterranean sub-shrub prized for its silver-gray foliage and intensely aromatic purple flower spikes. A classic companion for roses and an unmatched pollinator magnet, lavender thrives in the exact conditions that challenge many plants: poor, rocky, alkaline soil with excellent drainage and full sun. English lavender is the most cold-hardy species, reliably perennial in Zones 5–9. Fresh or dried flowers are widely used in sachets, essential oils, culinary applications, and dried arrangements.
Sweetwater County, Wyoming is in USDA Zone 5a. The average last spring frost is May 29 and the first fall frost is September 20, giving you a growing season of approximately 114 days.
At an elevation of 7,922 feet, Sweetwater County receives approximately 12.9 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Lavender to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Lavender successfully. Mulch heavily to conserve soil moisture.
Sweetwater County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.7
Drainage
Well Drained
Lavender Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Soil Compatibility in Sweetwater County
How your county's soil matches Lavender's growing requirements.
Soil pH
Your soil pH (6.2–7.7) overlaps with Lavender's range (6.5–7.5), though not a perfect match.
Soil Texture
The loam soil in Sweetwater County is excellent for Lavender — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Lavender.
Organic Matter
Organic matter is moderate (2.4%). Annual compost additions will help Lavender.
How to Plant Lavender
Lavender Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Lavender
Lavender needs approximately 0.3 inches of water per week (1.3" per month). Here's how your county's rainfall compares month by month.
| Month | Lavender Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 0.8" | 0" | ❄️ Dormant |
| Feb | — | 0.9" | 0" | ❄️ Dormant |
| Mar | — | 1" | 0" | ❄️ Dormant |
| Apr | — | 1.3" | 0" | ❄️ Dormant |
| May | 1.3" | 1.5" | 0" | ✅ Rainfall sufficient |
| Jun | 1.3" | 1" | 0.3" | 💧 Light watering |
| Jul | 1.3" | 1.1" | 0.2" | 💧 Light watering |
| Aug | 1.3" | 1.3" | 0" | ✅ Rainfall sufficient |
| Sep | 1.3" | 1" | 0.3" | 💧 Light watering |
| Oct | — | 1.2" | 0" | ❄️ Dormant |
| Nov | — | 1" | 0" | ❄️ Dormant |
| Dec | — | 0.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Sweetwater County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Lavender Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Lavender Planting Timeline — Sweetwater County, WY
Lavender Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 20 | Mar 20 – Apr 3 |
| Transplant Outdoors | June 19 | Jun 19 – Jul 3 |
| Bloom | August 28 | Aug 28 – Oct 9 |
Plant 0.5" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors |
| May | — |
| June | Transplant Outdoors |
| July | Transplant Outdoors |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.3"/week · Natural rainfall sufficient
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6.5–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 5a
📆 Growing Season
114 days in Sweetwater County
Growing Tips for Lavender in Sweetwater County
Direct sow Lavender outdoors after May 29 in Sweetwater County when soil has warmed and frost danger has passed.
Your 114.0-day growing season in Sweetwater County is tight for Lavender (90.0-120.0 days to maturity). Start indoors and choose early-maturing varieties.
General growing tips
The single most important requirement for lavender success is excellent drainage — it will rot in heavy clay or wet winter soils before cold alone kills it. Amend with coarse sand or fine gravel if needed; raised beds work well in Zones 5–6. Start from rooted cuttings or transplants rather than seed for named cultivars. Transplant after last frost when soil is reliably warm (55°F+). Avoid rich or overly moist soils. Prune lightly after each flush of bloom, but never cut into old wood below the green growth zone — it will not regenerate from leafless woody stems. In Zones 5–6, mulch lightly with gravel (not bark/organic material which traps moisture) around the crown for winter protection. Year 2+ plants develop into full, mature shrubs with the most prolific bloom.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Lavender in Other Locations
Frequently Asked Questions
When should I plant Lavender in Sweetwater County, WY?
Sweetwater County is in Zone 5a with an average last frost of May 29. Plan your Lavender planting based on this frost date — see the calendar above for exact timing.
What planting zone is Sweetwater County, WY?
Sweetwater County, Wyoming is in USDA Hardiness Zone 5a. The average last spring frost is May 29 and first fall frost is September 20.
Your Sweetwater County Garden Planner — Free
A 22-page printable planner built for Sweetwater County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.