When to plant Borage in Sioux County, IA
Plant Borage in Sioux County from April 17 to May 8 in spring. Sioux County sits in USDA Zone 5a, with last frost around May 1 and first frost on October 3. A second sowing from July 25 to August 8 extends the harvest into fall.
When to Plant Borage in Sioux County, IA
June in the garden — Sioux County, Iowa
June is a pivotal month for Sioux County, Iowa gardens. Focus on these tasks first and you'll set up the rest of the season for success.
-
Start borage under lights
A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.
-
Collect borage at their peak
Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.
Coming up in July — start thinking about
- First harvests: borage
- Fall sowing: borage
Borage is a self-seeding annual herb with star-shaped blue flowers that attract pollinators. Its leaves have a cucumber-like flavor and the flowers are edible.
Sioux County, Iowa is in USDA Zone 5a. The average last spring frost is May 1 and the first fall frost is October 3, giving you a growing season of approximately 155 days.
At an elevation of 1,212 feet, Sioux County receives approximately 39.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Borage to ensure they mature before fall.
Sioux County Soil Profile
Soil Type
Silt Loam
Soil pH
6.3-7
Drainage
Well Drained
Borage 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 Sioux County
How your county's soil matches Borage's growing requirements.
Soil pH
Your soil pH (6.3–7.0) is within Borage's preferred range (6.0–7.0).
Soil Texture
The silt loam soil in Sioux County is excellent for Borage — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.0%) — Borage will thrive.
How to Plant Borage
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Borage
Sow every 5.7 weeks. Last sowing by Aug 04 to harvest before frost.
For a dedicated fall crop, sow by Jul 25.
Borage Water Budget
Monthly Watering Guide for Borage
Borage 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 | Borage Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.8" | 0" | ❄️ Dormant |
| Feb | — | 1.7" | 0" | ❄️ Dormant |
| Mar | — | 3" | 0" | ❄️ Dormant |
| Apr | — | 4" | 0" | ❄️ Dormant |
| May | 2.2" | 4.8" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 4" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.8" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.4" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Sioux County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Borage 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.
Borage Planting Timeline — Sioux County, IA
Borage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 27 | Mar 27 – Apr 10 |
| Transplant Outdoors | April 24 | Apr 24 – May 8 |
| Direct Sow | April 17 | Apr 17 – May 8 |
| Harvest | June 19 | Jun 19 – Aug 7 |
| Fall Sowing | July 25 | Jul 25 – Aug 8 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Fall Sowing Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
50–60 days
🧪 Soil pH
Needs 6–7 · Your soil: ideal
🗺️ USDA Zone
Zone 5a
📆 Growing Season
155 days in Sioux County
Growing Tips for Borage in Sioux County
Direct sow Borage outdoors after May 01 in Sioux County when soil has warmed and frost danger has passed.
General growing tips
Direct sow in spring as borage does not transplant well. Allow some plants to go to seed for next year. Young leaves are best; older leaves become bristly.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Borage in Other Locations
Frequently Asked Questions
When should I plant Borage in Sioux County, IA?
Sioux County is in Zone 5a with an average last frost of May 1. Plan your Borage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Sioux County, IA?
Sioux County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is May 1 and first fall frost is October 3.
When should I plant Borage in Sioux County, IA?
In Sioux County, IA, plant Borage after the last frost (around May 1) and before the first frost (around October 3). Best results when soil holds above 50°F.
What growing zone is Sioux County, IA for Borage?
Sioux County sits in USDA Zone 5a. Borage grows reliably in zones 3a through 11b, so it's a good fit here.
Can Borage grow in Sioux County's climate?
Yes — Borage grows well in Sioux County's temperate climate. Sioux County averages a 155-day frost-free season, with last frost around May 1 and first frost around October 3.
Your Sioux County Garden Planner — Free
A 22-page printable planner built for Sioux County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.