When to Plant Chamomile in Benton County, WA
Chamomile is a daisy-like herb famous for its calming, apple-scented tea. German chamomile is an annual while Roman chamomile is a perennial ground cover.
Benton County, Washington is in USDA Zone 7a. The average last spring frost is April 3 and the first fall frost is October 27, giving you a growing season of approximately 207 days.
At an elevation of 2,633 feet, Benton County receives approximately 22.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Chamomile during the growing season.
Benton County Soil Profile
Soil Type
Silt Loam
Soil pH
5.5-6.3
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 Benton County
How your county's soil matches Chamomile's growing requirements.
Soil pH
Your soil pH (5.5–6.3) overlaps with Chamomile's range (5.6–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Benton County is excellent for Chamomile — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.6%) — Chamomile will thrive.
How to Plant Chamomile
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Chamomile
Sow every 6.9 weeks. Last sowing by Jul 29 to harvest before frost.
For a dedicated fall crop, sow by Aug 18.
Plant Water Budget
Monthly Watering Guide for Chamomile
Chamomile needs approximately 0.4 inches of water per week (1.7" per month). Here's how your county's rainfall compares month by month.
| Month | Chamomile Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.2" | 0" | ❄️ Dormant |
| Feb | — | 2.6" | 0" | ❄️ Dormant |
| Mar | — | 2.1" | 0" | ❄️ Dormant |
| Apr | 1.7" | 1.5" | 0.2" | 💧 Light watering |
| May | 1.7" | 1.4" | 0.3" | 💧 Light watering |
| Jun | 1.7" | 0.9" | 0.8" | 💧 Light watering |
| Jul | 1.7" | 0.4" | 1.3" | 🚿 Regular watering |
| Aug | 1.7" | 0.4" | 1.3" | 🚿 Regular watering |
| Sep | 1.7" | 0.8" | 0.9" | 🚿 Regular watering |
| Oct | 1.7" | 2" | 0" | ✅ Rainfall sufficient |
| Nov | — | 3.7" | 0" | ❄️ Dormant |
| Dec | — | 3.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Benton County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Chamomile 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.
Chamomile Planting Timeline — Benton County, WA
Chamomile Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 27 | Feb 27 – Mar 13 |
| Transplant Outdoors | March 27 | Mar 27 – Apr 10 |
| Direct Sow | March 20 | Mar 20 – Apr 10 |
| Harvest | May 29 | May 29 – Aug 7 |
| Fall Sowing | August 18 | Aug 18 – Sep 1 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.4"/week · Natural rainfall sufficient
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 5.6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 7a
📆 Growing Season
207 days in Benton County
Growing Tips for Chamomile in Benton County
Direct sow Chamomile outdoors after April 03 in Benton County when soil has warmed and frost danger has passed.
Common pests for Chamomile in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow on the soil surface as seeds need light. Harvest flowers when petals begin to curl back. Chamomile self-sows freely and improves the health of nearby plants.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Chamomile in Other Locations
Frequently Asked Questions
When should I plant Chamomile in Benton County, WA?
Benton County is in Zone 7a with an average last frost of April 3. Plan your Chamomile planting based on this frost date — see the calendar above for exact timing.
What planting zone is Benton County, WA?
Benton County, Washington is in USDA Hardiness Zone 7a. The average last spring frost is April 3 and first fall frost is October 27.
Plan Your Garden with Confidence
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