When to Plant Asparagus in St. Francois County, MO
Top priorities for St. Francois County, Missouri gardeners in May
We've pulled the most time-sensitive tasks for St. Francois County, Missouri this May and put them front and centre. Tackle them in order.
Asparagus is a long-lived perennial vegetable that produces tender spears each spring for 15-20 years once established. It requires patience but rewards with reliable harvests.
St. Francois County, Missouri is in USDA Zone 6b. The average last spring frost is April 16 and the first fall frost is October 21, giving you a growing season of approximately 188 days.
At an elevation of 808 feet, St. Francois County receives approximately 41 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Asparagus during the growing season.
St. Francois County Soil Profile
Soil Type
Silt Loam
Soil pH
5.3-7
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 St. Francois County
How your county's soil matches Asparagus's growing requirements.
Soil pH
Your soil pH (5.3–7.0) is more acidic than Asparagus prefers (6.5–7.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in St. Francois County is excellent for Asparagus — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Asparagus.
Organic Matter
Organic matter is moderate (2.9%). Annual compost additions will help Asparagus.
How to Plant Asparagus
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Asparagus
Asparagus needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.
| Month | Asparagus Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.8" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | 3.5" | 4.3" | 0" | ✅ Rainfall sufficient |
| May | 3.5" | 5.4" | 0" | ✅ Rainfall sufficient |
| Jun | 3.5" | 5" | 0" | ✅ Rainfall sufficient |
| Jul | 3.5" | 4.2" | 0" | ✅ Rainfall sufficient |
| Aug | 3.5" | 4.6" | 0" | ✅ Rainfall sufficient |
| Sep | 3.5" | 3.1" | 0.4" | 💧 Light watering |
| Oct | 3.5" | 3.6" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.9" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in St. Francois County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Asparagus 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.
Asparagus Planting Timeline — St. Francois County, MO
Asparagus Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 30 | Apr 30 – May 14 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | — |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.8"/week · Natural rainfall sufficient
📅 Days to Maturity
730–1095 days
🧪 Soil pH
Needs 6.5–7.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 6b
📆 Growing Season
188 days in St. Francois County
Growing Tips for Asparagus in St. Francois County
Direct sow Asparagus outdoors after April 16 in St. Francois County when soil has warmed and frost danger has passed.
Your 188.0-day growing season in St. Francois County is tight for Asparagus (730.0-1095.0 days to maturity). Start indoors and choose early-maturing varieties.
General growing tips
Plant crowns in deep trenches with compost. Do not harvest spears for the first two years to allow root establishment. Mulch heavily to suppress weeds and retain moisture.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Asparagus in Other Locations
Frequently Asked Questions
When should I plant Asparagus in St. Francois County, MO?
St. Francois County is in Zone 6b with an average last frost of April 16. Plan your Asparagus planting based on this frost date — see the calendar above for exact timing.
What planting zone is St. Francois County, MO?
St. Francois County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 16 and first fall frost is October 21.
Your St. Francois County Garden Planner — Free
A 24-page printable planner built for St. Francois County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.