When to Plant Dill in Multnomah County, OR
Multnomah County, Oregon gardeners: here's your May plan
If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.
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Sow dill in trays indoors
Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.
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Start harvesting dill
If you can't use it all right away, check the food-preservation section of your planner.
Before June arrives, get these ready
- First harvests: dill
Dill is a feathery annual herb with aromatic leaves and seeds. Its fine foliage and umbrella-shaped flower heads attract beneficial insects to the garden.
Multnomah County, Oregon is in USDA Zone 9a. The average last spring frost is April 14 and the first fall frost is October 27, giving you a growing season of approximately 196 days.
At an elevation of 357 feet, Multnomah County receives approximately 35.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Dill to ensure they mature before fall.
Multnomah County Soil Profile
Soil Type
Silt Loam
Soil pH
5.8-6.3
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 Multnomah County
How your county's soil matches Dill's growing requirements.
Soil pH
Your soil pH (5.8–6.3) is within Dill's preferred range (5.5–7.0).
Soil Texture
The silt loam soil in Multnomah County is excellent for Dill — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Dill.
Organic Matter
Organic matter is excellent (4.5%) — Dill will thrive.
How to Plant Dill
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Dill
Sow every 4.6 weeks. Last sowing by Aug 28 to harvest before frost.
For a dedicated fall crop, sow by Sep 01.
Plant Water Budget
Monthly Watering Guide for Dill
Dill 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 | Dill Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 5.8" | 0" | ❄️ Dormant |
| Feb | — | 4.1" | 0" | ❄️ Dormant |
| Mar | — | 3.5" | 0" | ❄️ Dormant |
| Apr | 2.2" | 2.3" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 2.3" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 1.3" | 0.9" | 💧 Light watering |
| Jul | 2.2" | 0.6" | 1.6" | 🚿 Regular watering |
| Aug | 2.2" | 0.7" | 1.5" | 🚿 Regular watering |
| Sep | 2.2" | 1.6" | 0.6" | 💧 Light watering |
| Oct | 2.2" | 2.9" | 0" | ✅ Rainfall sufficient |
| Nov | — | 6" | 0" | ❄️ Dormant |
| Dec | — | 4.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Multnomah County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Dill 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.
Dill Planting Timeline — Multnomah County, OR
Dill Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 17 | Mar 17 – Mar 31 |
| Transplant Outdoors | April 7 | Apr 7 – Apr 21 |
| Direct Sow | March 24 | Mar 24 – Apr 14 |
| Harvest | May 19 | May 19 – Jul 21 |
| Fall Sowing | September 1 | Sep 1 – Sep 15 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
40–60 days
🧪 Soil pH
Needs 5.5–7 · Your soil: ideal
🗺️ USDA Zone
Zone 9a
📆 Growing Season
196 days in Multnomah County
Growing Tips for Dill in Multnomah County
Direct sow Dill outdoors after April 14 in Multnomah County when soil has warmed and frost danger has passed.
Your generous 196.0-day season in Multnomah County allows multiple plantings of Dill. Sow every 20.0 days for continuous harvest.
Common pests for Dill in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow in spring as dill has a taproot and dislikes transplanting. Succession sow for continuous leaf harvest. Allow some plants to flower for seeds and to attract beneficial insects.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Dill in Other Locations
Frequently Asked Questions
When should I plant Dill in Multnomah County, OR?
Multnomah County is in Zone 9a with an average last frost of April 14. Plan your Dill planting based on this frost date — see the calendar above for exact timing.
What planting zone is Multnomah County, OR?
Multnomah County, Oregon is in USDA Hardiness Zone 9a. The average last spring frost is April 14 and first fall frost is October 27.
Your Multnomah County Garden Planner — Free
A 24-page printable planner built for Multnomah County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.