When to Plant Hyssop in Washington County, UT
May in Washington County, Utah — your action list
We've pulled the most time-sensitive tasks for Washington County, Utah this May and put them front and centre. Tackle them in order.
June prep starts now
- First harvests: hyssop
Hyssop is a semi-evergreen perennial herb with intense blue flower spikes that attract bees and butterflies. It has a minty, slightly bitter flavor used in liqueurs and teas.
Washington County, Utah is in USDA Zone 8b. The average last spring frost is April 6 and the first fall frost is November 1, giving you a growing season of approximately 209 days.
At an elevation of 3,524 feet, Washington County receives approximately 12.7 inches of rainfall annually with predominantly loam soil. Summer highs average 90°F, providing good warmth for Hyssop during the growing season. With low rainfall, drip irrigation is essential for growing Hyssop successfully. Mulch heavily to conserve soil moisture.
Washington County Soil Profile
Soil Type
Loam
Soil pH
6.7-8
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 Washington County
How your county's soil matches Hyssop's growing requirements.
Soil pH
Your soil pH (6.7–8.0) is within Hyssop's preferred range (6.0–8.0).
Soil Texture
The loam soil in Washington County is excellent for Hyssop — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Hyssop.
Organic Matter
Organic matter is moderate (2.4%). Annual compost additions will help Hyssop.
How to Plant Hyssop
Succession Planting Hyssop
Sow every 8 weeks. Last sowing by Aug 03 to harvest before frost.
Plant Water Budget
Water stress score is 10/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Hyssop
Hyssop needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Hyssop Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1" | 0" | ❄️ Dormant |
| Feb | — | 0.6" | 0" | ❄️ Dormant |
| Mar | — | 1.1" | 0" | ❄️ Dormant |
| Apr | 2.2" | 1.2" | 1" | 💧 Light watering |
| May | 2.2" | 1.4" | 0.8" | 💧 Light watering |
| Jun | 2.2" | 0.9" | 1.3" | 🚿 Regular watering |
| Jul | 2.2" | 1.2" | 1" | 💧 Light watering |
| Aug | 2.2" | 1.4" | 0.8" | 💧 Light watering |
| Sep | 2.2" | 0.9" | 1.3" | 🚿 Regular watering |
| Oct | 2.2" | 1.2" | 1" | 💧 Light watering |
| Nov | 2.2" | 1" | 1.2" | 🚿 Regular watering |
| Dec | — | 0.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in Washington County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Hyssop 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.
Hyssop Planting Timeline — Washington County, UT
Hyssop Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 13 | Apr 13 – Apr 27 |
| Harvest | June 22 | Jun 22 – Aug 24 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · 1-2 times/week
📅 Days to Maturity
70–90 days
🧪 Soil pH
Needs 6–8 · Your soil: ideal
🗺️ USDA Zone
Zone 8b
📆 Growing Season
209 days in Washington County
Growing Tips for Hyssop in Washington County
Direct sow Hyssop outdoors after April 06 in Washington County when soil has warmed and frost danger has passed.
Washington County receives only 13" of rain annually. Hyssop needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors or direct sow in spring. Prune back in early spring to encourage bushy growth. Hyssop is drought-tolerant once established and thrives in poor soil.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Hyssop in Other Locations
Frequently Asked Questions
When should I plant Hyssop in Washington County, UT?
Washington County is in Zone 8b with an average last frost of April 6. Plan your Hyssop planting based on this frost date — see the calendar above for exact timing.
What planting zone is Washington County, UT?
Washington County, Utah is in USDA Hardiness Zone 8b. The average last spring frost is April 6 and first fall frost is November 1.
Your Washington County Garden Planner — Free
A 24-page printable planner built for Washington County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.