When to Plant Dill in Riverside County, CA
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.
Riverside County, California is in USDA Zone 9b. The average last spring frost is February 24 and the first fall frost is December 4, giving you a growing season of approximately 283 days.
At an elevation of 1,206 feet, Riverside County receives approximately 15.5 inches of rainfall annually with predominantly loam soil. Summer highs average 102°F, so Dill may need afternoon shade and extra watering during peak heat. With low rainfall, drip irrigation is essential for growing Dill successfully. Mulch heavily to conserve soil moisture.
Riverside County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.8
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.
Plant Water Budget
Water stress score is 10/10 — consider drought-tolerant varieties and mulching
Dill Planting Timeline — Riverside County, CA
Dill Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 27 | Jan 27 – Feb 10 |
| Transplant Outdoors | February 17 | Feb 17 – Mar 3 |
| Direct Sow | February 3 | Feb 3 – Feb 24 |
| Fall Sowing | October 9 | Oct 9 – Oct 23 |
| Harvest | March 31 | Mar 31 – Jun 2 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors Transplant Outdoors Direct Sow |
| March | Transplant Outdoors Harvest |
| April | Harvest |
| May | Harvest |
| June | Harvest |
| July | — |
| August | — |
| September | — |
| October | Fall Sowing |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
40–60 days
Soil pH
5.5 – 7
USDA Zone
Zone 9b
Growing Season
283 days
Growing Tips for Riverside County
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
Level Up Your Garden
Dill in Other Locations
Frequently Asked Questions
When should I plant Dill in Riverside County, CA?
Riverside County is in Zone 9b with an average last frost of February 24. Plan your Dill planting based on this frost date — see the calendar above for exact timing.
What planting zone is Riverside County, CA?
Riverside County, California is in USDA Hardiness Zone 9b. The average last spring frost is February 24 and first fall frost is December 4.
Plan Your Garden with Confidence
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