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When to plant Coreopsis in Silver Bow County, MT

In Silver Bow County, Coreopsis is a spring-only crop. Plant June 22–July 13 once soil hits 50°F.

When to Plant Coreopsis in Silver Bow County, MT

Coreopsis (Tickseed) is a cheerful, long-blooming native perennial that produces a continuous flush of bright yellow, gold, or bi-colored daisy-like flowers from early summer well into fall. One of the most reliable cut-and-come-again bloomers in the perennial garden, it thrives in hot, dry, sunny conditions and poor soil where many competitors struggle. An invaluable nectar source for native bees and butterflies, and a butterfly host plant for several species.

Silver Bow County, Montana is in USDA Zone 5a. The average last spring frost is June 15 and the first fall frost is September 7, giving you a growing season of approximately 84 days.

At an elevation of 5,305 feet, Silver Bow County receives approximately 14.3 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Coreopsis to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Coreopsis successfully. Mulch heavily to conserve soil moisture.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting
Silver Bow County, MT (Zone 5a) Very short season
84 days
Last Spring Frost June 15
84 growing days
First Fall Frost September 7

Silver Bow County Soil Profile

Soil Type

Loam

Soil pH

6.6-8.3

Drainage

Well Drained

Monthly Watering Guide for Coreopsis

Coreopsis needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Coreopsis Needs Rainfall You Supplement Action
Jan 1.1" 0" ❄️ Dormant
Feb 1" 0" ❄️ Dormant
Mar 1.3" 0" ❄️ Dormant
Apr 1.4" 0" ❄️ Dormant
May 1.5" 0" ❄️ Dormant
Jun 4.3" 0.9" 3.4" 🚿 Regular watering
Jul 4.3" 1.1" 3.2" 🚿 Regular watering
Aug 4.3" 1.8" 2.5" 🚿 Regular watering
Sep 4.3" 1.1" 3.2" 🚿 Regular watering
Oct 1.1" 0" ❄️ Dormant
Nov 1" 0" ❄️ Dormant
Dec 0.9" 0" ❄️ Dormant

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

Coreopsis Planting Timeline — Silver Bow County, MT

Coreopsis Planting Calendar

Activity When Date Range
Start Indoors April 13 Apr 13 – Apr 27
Transplant Outdoors June 29 Jun 29 – Jul 13
Direct Sow June 22 Jun 22 – Jul 13
Bloom September 7 Sep 7 – Dec 14

Plant 0.1" deep · 18" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

60–80 days

🧪 Soil pH

Needs 5.5–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 5a

📆 Growing Season

84 days in Silver Bow County

Growing Tips for Silver Bow County

Start seeds indoors 8–10 weeks before last frost or direct sow after last frost. Seeds germinate easily without stratification. Thrives in poor to average, well-drained soil — rich soil promotes foliage over flowers. Drought tolerant once established; overwatering is the most common mistake. Deadhead spent blooms to maintain continuous flowering through the season. Shear plants by one-third in midsummer for a fresh flush of late-season blooms. Year 2+ plants bloom most heavily. Divide every 2–3 years in early spring to rejuvenate crowded clumps.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Coreopsis in Silver Bow County, MT?

Silver Bow County is in Zone 5a with an average last frost of June 15. Plan your Coreopsis planting based on this frost date — see the calendar above for exact timing.

What planting zone is Silver Bow County, MT?

Silver Bow County, Montana is in USDA Hardiness Zone 5a. The average last spring frost is June 15 and first fall frost is September 7.

When should I plant Coreopsis in Silver Bow County, MT?

In Silver Bow County, MT, plant Coreopsis after the last frost (around June 15) and before the first frost (around September 7). Best results when soil holds above 50°F.

What growing zone is Silver Bow County, MT for Coreopsis?

Silver Bow County sits in USDA Zone 5a. Coreopsis grows reliably in zones 3a through 9b, so it's a good fit here.

Can Coreopsis grow in Silver Bow County's climate?

Yes — Coreopsis grows well in Silver Bow County's temperate climate. Silver Bow County averages a 84-day frost-free season, with last frost around June 15 and first frost around September 7.

🌱

Your Silver Bow County Garden Planner — Free

A 22-page printable planner built for Silver Bow 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.

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

Sources & credits

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