When to Plant Valerian in Yellowstone County, MT
Your April planting checklist for Yellowstone County, Montana
Your garden in Yellowstone County, Montana is working on a schedule, even when you're not. Here's where you should be this April.
A few tasks this April that'll pay off in May
- Transplants going out: valerian
Valerian is a tall perennial herb with fragrant white or pink flower clusters, valued for its root which is used as a natural sleep aid. It attracts pollinators and earthworms.
Yellowstone County, Montana is in USDA Zone 4b. The average last spring frost is May 9 and the first fall frost is October 3, giving you a growing season of approximately 147 days.
At an elevation of 7,432 feet, Yellowstone County receives approximately 21.1 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Valerian to ensure they mature before fall.
Yellowstone County Soil Profile
Soil Type
Loam
Soil pH
6.2-8
Drainage
Well Drained
Plant 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 Yellowstone County
How your county's soil matches Valerian's growing requirements.
Soil pH
Your soil pH (6.2–8.0) is more alkaline than Valerian prefers (5.5–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Yellowstone County is excellent for Valerian — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Valerian.
Organic Matter
Organic matter is moderate (2.4%). Annual compost additions will help Valerian.
How to Plant Valerian
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Valerian
Valerian needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Valerian Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1.2" | 0" | ❄️ Dormant |
| Mar | — | 1.9" | 0" | ❄️ Dormant |
| Apr | — | 1.9" | 0" | ❄️ Dormant |
| May | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| Jun | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Jul | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Aug | 4.3" | 2.5" | 1.8" | 💧 Light watering |
| Sep | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Oct | 4.3" | 1.8" | 2.5" | 🚿 Regular watering |
| Nov | — | 1.6" | 0" | ❄️ Dormant |
| Dec | — | 1.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Yellowstone County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Valerian 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.
Valerian Planting Timeline — Yellowstone County, MT
Valerian Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 16 | May 16 – May 30 |
| Harvest | September 19 | Sep 19 – Oct 10 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | — |
| August | — |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · 2-3 times/week
📅 Days to Maturity
120–180 days
🧪 Soil pH
Needs 5.5–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 4b
📆 Growing Season
147 days in Yellowstone County
Growing Tips for Valerian in Yellowstone County
Direct sow Valerian outdoors after May 09 in Yellowstone County when soil has warmed and frost danger has passed.
Your 147.0-day growing season in Yellowstone County is tight for Valerian (120.0-180.0 days to maturity). Start indoors and choose early-maturing varieties.
Yellowstone County receives only 21" of rain annually. Valerian needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors and transplant after last frost. Harvest roots in fall of the second year. Deadhead flowers unless you want self-seeding. Cats are attracted to valerian root.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Valerian in Other Locations
Frequently Asked Questions
When should I plant Valerian in Yellowstone County, MT?
Yellowstone County is in Zone 4b with an average last frost of May 9. Plan your Valerian planting based on this frost date — see the calendar above for exact timing.
What planting zone is Yellowstone County, MT?
Yellowstone County, Montana is in USDA Hardiness Zone 4b. The average last spring frost is May 9 and first fall frost is October 3.
Your Yellowstone County Garden Planner — Free
A 24-page printable planner built for Yellowstone County (Zone 4b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.