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When to plant Larkspur in Smith County County,

Aim to plant Larkspur in Smith County County on or after March 26; the window stays open through April 16. Smith County County's 174-day frost-free season gives you a single solid spring crop with a brief fall option.

When to Plant Larkspur in Smith County, KS

Smith County, Kansas Zone 6a June

Your June planting checklist for Smith County, Kansas

Here's what deserves your attention in Smith County, Kansas this month. Everything below is tailored to Zone 6a and timed around your local frost dates.

Avg. last frost April 23
Avg. first frost October 14
Soil temp (4") 68°F
Watering Low
Pest pressure High
Daylight 14.8 hrs
  1. Pick larkspur

    If you can't use it all right away, check the food-preservation section of your planner.

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  • First harvests: larkspur

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Larkspur (Consolida ajacis) is a cool-season annual that produces tall, delicate spires of blue, purple, pink, and white flowers reminiscent of its perennial cousin, delphinium. Direct-sown into cold soil or fall-sown in mild-winter climates, it blooms in spring before going to seed as summer heat arrives. An excellent cut flower and cottage-garden staple.

Smith County, Kansas is in USDA Zone 6a. The average last spring frost is April 23 and the first fall frost is October 14, giving you a growing season of approximately 174 days.

At an elevation of 1,048 feet, Smith County receives approximately 26.2 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Larkspur to ensure they mature before fall.

Annual Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
Smith County, KS (Zone 6a) Moderate season
174 days
Last Spring Frost April 23
174 growing days
First Fall Frost October 14
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Smith County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.3

Drainage

Well Drained

Larkspur Planting Risk Windows

Early Start (70% safe) ✓ Fits season (50 days to spare)
Transplant: Apr 17 🌸 Bloom: Jun 26 – Aug 21
Recommended (50%) ✓ Fits season (48 days to spare)
Transplant: Apr 23 🌸 Bloom: Jul 2 – Aug 27
Safe Start (90%) ✓ Fits season (43 days to spare)
Transplant: May 10 🌸 Bloom: Jul 19 – Sep 13

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 Smith County

How your county's soil matches Larkspur's growing requirements.

Soil pH

Your soil pH (6.5–7.3) overlaps with Larkspur's range (6.0–7.0), though not a perfect match.

Soil Texture

The loam soil in Smith County is excellent for Larkspur — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Larkspur.

Organic Matter

Organic matter is moderate (3.4%). Annual compost additions will help Larkspur.

How to Plant Larkspur

0.1"
Planting Depth
8"
Between Plants
12"
Between Rows

Succession Planting Larkspur

3
successive plantings in your 174-day season

Sow every 6.9 weeks. Last sowing by Jul 16 to harvest before frost.

Larkspur Water Budget

Plant needs
0.5″/week
Rainfall provides
0.6″/week
You supply
0.0″/week
Watering frequency Only during dry spells
Season total 33 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Larkspur

Larkspur 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 Larkspur Needs Rainfall You Supplement Action
Jan 0.7" 0" ❄️ Dormant
Feb 1" 0" ❄️ Dormant
Mar 1.7" 0" ❄️ Dormant
Apr 2.2" 2.6" 0" ✅ Rainfall sufficient
May 2.2" 3.7" 0" ✅ Rainfall sufficient
Jun 2.2" 4.1" 0" ✅ Rainfall sufficient
Jul 2.2" 3" 0" ✅ Rainfall sufficient
Aug 2.2" 3.4" 0" ✅ Rainfall sufficient
Sep 2.2" 2.3" 0" ✅ Rainfall sufficient
Oct 2.2" 1.9" 0.3" 💧 Light watering
Nov 1" 0" ❄️ Dormant
Dec 0.8" 0" ❄️ Dormant

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

Larkspur 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.

Larkspur needs ~975 GDD — county provides 2,262 GDD Excellent fit

Larkspur Planting Timeline — Smith County, KS

Larkspur Planting Calendar

Activity When Date Range
Direct Sow March 26 Mar 26 – Apr 16
Bloom June 4 Jun 4 – Jul 30

Plant 0.1" deep · 8" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March Direct Sow
April Direct Sow
May
June Bloom
July Bloom
August
September
October
November
December
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Only during dry spells

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6a

📆 Growing Season

174 days in Smith County

Growing Tips for Larkspur in Smith County

Direct sow Larkspur outdoors after April 23 in Smith County when soil has warmed and frost danger has passed.

General growing tips

Larkspur does not transplant well — direct-sow only. In cold climates (zones 2–6), sow directly in early spring as soon as soil can be worked, 4–6 weeks before last frost; cold soil improves germination. In zones 7–10, fall-sow 8–10 weeks before first frost for spring bloom. Press seeds lightly into soil; they need darkness to germinate — cover with 1/8–1/4 inch of soil. Thin to 6–12 inches to prevent powdery mildew. Allow seed pods to mature and self-sow for naturalized colonies. All parts are toxic if ingested.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Larkspur in Smith County, KS?

Smith County is in Zone 6a with an average last frost of April 23. Plan your Larkspur planting based on this frost date — see the calendar above for exact timing.

What planting zone is Smith County, KS?

Smith County, Kansas is in USDA Hardiness Zone 6a. The average last spring frost is April 23 and first fall frost is October 14.

When should I plant Larkspur in Smith County, ?

In Smith County, , plant Larkspur after the last frost (around April 23) and before the first frost (around October 14). Best results when soil holds above 50°F.

What growing zone is Smith County, for Larkspur?

Smith County sits in USDA Zone 6a. Larkspur grows reliably in zones 2a through 10b, so it's a good fit here.

Can Larkspur grow in Smith County's climate?

Yes — Larkspur grows well in Smith County's temperate climate. Smith County averages a 174-day frost-free season, with last frost around April 23 and first frost around October 14.

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Your Smith County Garden Planner — Free

A 22-page printable planner built for Smith County (Zone 6a). 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 Smith County, KS. 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.