Blog

When to plant Impatiens in Frederick County, MD

Frederick County sits in cold Zone 7a. Plant Impatiens April 23–May 7 for the single annual harvest; the October 23 first frost closes the window.

When to Plant Impatiens in Frederick County, MD

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.

Frederick County, Maryland is in USDA Zone 7a. The average last spring frost is April 16 and the first fall frost is October 23, giving you a growing season of approximately 190 days.

At an elevation of 756 feet, Frederick County receives approximately 49.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Impatiens during the growing season.

Annual Blooms in Summer Pollinator-friendly
Frederick County, MD (Zone 7a) Moderate season
190 days
Last Spring Frost April 16
190 growing days
First Fall Frost October 23

Frederick County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.8

Drainage

Well Drained

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 3.3" 0" ❄️ Dormant
Feb 3" 0" ❄️ Dormant
Mar 3.8" 0" ❄️ Dormant
Apr 4.3" 4.9" 0" ✅ Rainfall sufficient
May 4.3" 4" 0.3" 💧 Light watering
Jun 4.3" 4.1" 0.2" 💧 Light watering
Jul 4.3" 5.7" 0" ✅ Rainfall sufficient
Aug 4.3" 4" 0.3" 💧 Light watering
Sep 4.3" 4.4" 0" ✅ Rainfall sufficient
Oct 4.3" 4" 0.3" 💧 Light watering
Nov 4.1" 0" ❄️ Dormant
Dec 4.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Frederick County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Impatiens Planting Timeline — Frederick County, MD

Impatiens Planting Calendar

Activity When Date Range
Start Indoors February 19 Feb 19 – Mar 5
Transplant Outdoors April 23 Apr 23 – May 7
Bloom July 2 Jul 2 – Oct 22

· 10" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors
April Transplant Outdoors
May Transplant Outdoors
June
July Bloom
August Bloom
September Bloom
October Bloom
November
December

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

60–75 days

🧪 Soil pH

Needs 6–6.5 · Your soil: N/A

🗺️ USDA Zone

Zone 7a

📆 Growing Season

190 days in Frederick County

Growing Tips for Frederick County

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 →

Frequently Asked Questions

When should I plant Impatiens in Frederick County, MD?

Frederick County is in Zone 7a with an average last frost of April 16. Plan your Impatiens planting based on this frost date — see the calendar above for exact timing.

What planting zone is Frederick County, MD?

Frederick County, Maryland is in USDA Hardiness Zone 7a. The average last spring frost is April 16 and first fall frost is October 23.

When should I plant Impatiens in Frederick County, MD?

In Frederick County, MD, plant Impatiens after the last frost (around April 16) and before the first frost (around October 23). Best results when soil holds above 50°F.

What growing zone is Frederick County, MD for Impatiens?

Frederick County sits in USDA Zone 7a. Impatiens grows reliably in zones 2a through 11b, so it's a good fit here.

Can Impatiens grow in Frederick County's climate?

Yes — Impatiens grows well in Frederick County's temperate climate. Frederick County averages a 190-day frost-free season, with last frost around April 16 and first frost around October 23.

🌱

Your Frederick County Garden Planner — Free

A 22-page printable planner built for Frederick County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Frederick County, MD. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.