When to plant Impatiens in Howard County, MO
Plant Impatiens in Howard County, between April 20 and May 4 — the only viable window. Zone 6b's short season (194 frost-free days) rules out a fall crop.
When to Plant Impatiens in Howard County, MO
What to do in June
Your Howard County, Missouri garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.
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Get impatiens seeds going inside
Label every cell. You will absolutely forget which is which otherwise.
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Pick impatiens
If you can't use it all right away, check the food-preservation section of your planner.
Looking ahead to July
- First harvests: impatiens
Impatiens (Impatiens walleriana) are the go-to annual for shaded beds and containers. They produce a continuous carpet of flat-faced blooms from transplant until frost, needing little deadheading. Their preference for consistent moisture and part-shade makes them ideal under trees and along north-facing borders.
Howard County, Missouri is in USDA Zone 6b. The average last spring frost is April 13 and the first fall frost is October 24, giving you a growing season of approximately 194 days.
At an elevation of 945 feet, Howard County receives approximately 41.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Impatiens during the growing season.
Howard County Soil Profile
Soil Type
Silt Loam
Soil pH
5.6-6.9
Drainage
Well Drained
Impatiens 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 Howard County
How your county's soil matches Impatiens's growing requirements.
Soil pH
Your soil pH (5.6–6.9) overlaps with Impatiens's range (6.0–6.5), though not a perfect match.
Soil Texture
The silt loam soil in Howard County is excellent for Impatiens — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Impatiens.
How to Plant Impatiens
Succession Planting Impatiens
Sow every 6.9 weeks. Last sowing by Aug 10 to harvest before frost.
Impatiens Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Impatiens
Impatiens needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Impatiens Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.8" | 0" | ❄️ Dormant |
| Feb | — | 1.9" | 0" | ❄️ Dormant |
| Mar | — | 2.5" | 0" | ❄️ Dormant |
| Apr | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| May | 4.3" | 4.9" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 5.4" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Sep | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Oct | 4.3" | 3.1" | 1.2" | 💧 Light watering |
| Nov | — | 3.2" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Howard County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Impatiens 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.
Impatiens Planting Timeline — Howard County, MO
Impatiens Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 16 | Feb 16 – Mar 2 |
| Transplant Outdoors | April 20 | Apr 20 – May 4 |
| Bloom | June 29 | Jun 29 – Oct 12 |
· 10" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
60–75 days
🧪 Soil pH
Needs 6–6.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
194 days in Howard County
Growing Tips for Impatiens in Howard County
Direct sow Impatiens outdoors after April 13 in Howard County when soil has warmed and frost danger has passed.
General growing tips
Start seeds indoors 8–10 weeks before last frost at 70–75°F; germination requires light — do not cover seeds. Transplant after last frost once nights consistently exceed 50°F. Water regularly — wilting causes bud drop and they rarely fully recover the same flush. Watch for impatiens downy mildew (IDM); consider New Guinea impatiens as a resistant alternative in affected regions. Pinch tips at planting to encourage branching.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Impatiens in Other Locations
Frequently Asked Questions
When should I plant Impatiens in Howard County, MO?
Howard County is in Zone 6b with an average last frost of April 13. Plan your Impatiens planting based on this frost date — see the calendar above for exact timing.
What planting zone is Howard County, MO?
Howard County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 13 and first fall frost is October 24.
When should I plant Impatiens in Howard County, MO?
In Howard County, MO, plant Impatiens after the last frost (around April 13) and before the first frost (around October 24). Best results when soil holds above 50°F.
What growing zone is Howard County, MO for Impatiens?
Howard County sits in USDA Zone 6b. Impatiens grows reliably in zones 2a through 11b, so it's a good fit here.
Can Impatiens grow in Howard County's climate?
Yes — Impatiens grows well in Howard County's temperate climate. Howard County averages a 194-day frost-free season, with last frost around April 13 and first frost around October 24.
Your Howard County Garden Planner — Free
A 22-page printable planner built for Howard 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.