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When to Plant Larkspur in Progreso, TX

Hidalgo County, Texas Zone 10a July

This month in Hidalgo County, Texas

Each item below is timed to Hidalgo County, Texas's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost February 6
Avg. first frost December 18
Soil temp (4") 86°F
Watering Low
Pest pressure High
Daylight 13.5 hrs
  1. Plan the fall garden

    Make a planting map for August. Tomatoes, peppers, brassicas, lettuce, root crops all go in over the next 8 weeks. Soil amendments and irrigation prep happen now.

  2. Keep heat-survivor crops productive

    Daily harvest of okra and southern peas keeps plants producing. Let pods over-mature and the plant stops setting new fruit.

  3. Watch for hurricane prep season

    August-October is hurricane season. Stake young trees, secure rain barrels, and plan how to protect tender transplants from high winds.

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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.

Progreso, Texas is in USDA Zone 10a. The average last spring frost is February 6 and the first fall frost is December 18, giving you a growing season of approximately 315 days.

At an elevation of 4,081 feet, Hidalgo County receives approximately 67 inches of rainfall annually with predominantly loam soil. Summer highs average 100°F, so Larkspur may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Larkspur root diseases.

Annual Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
Progreso, TX (Zone 10a) Year-round
315 days
Last Spring Frost February 6
315 growing days
First Fall Frost December 18

Progreso Soil Profile

Soil Type

Loam

Soil pH

6.2-7.8

Drainage

Well Drained

Larkspur Planting Risk Windows

Early Start (70% safe) ✓ Fits season (188 days to spare)
Transplant: Jan 18 🌸 Bloom: Mar 29 – Jun 7
Recommended (50%) ✓ Fits season (175 days to spare)
Transplant: Feb 6 🌸 Bloom: Apr 17 – Jun 26
Safe Start (90%) ✓ Fits season (155 days to spare)
Transplant: Mar 5 🌸 Bloom: May 14 – Jul 23

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 Progreso

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

Soil pH

Your soil pH (6.2–7.8) overlaps with Larkspur's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.3%). Annual compost additions will help Larkspur.

How to Plant Larkspur

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

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Larkspur

6
successive plantings in your 315-day season

Sow every 6.9 weeks. Last sowing by Sep 19 to harvest before frost.

For a dedicated fall crop, sow by Oct 23.

Larkspur Water Budget

Plant needs
0.5″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

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 1.4" 0" ❄️ Dormant
Feb 2.2" 2.1" 0.1" 💧 Light watering
Mar 2.2" 3.6" 0" ✅ Rainfall sufficient
Apr 2.2" 6.7" 0" ✅ Rainfall sufficient
May 2.2" 10.1" 0" ✅ Rainfall sufficient
Jun 2.2" 9.4" 0" ✅ Rainfall sufficient
Jul 2.2" 9.3" 0" ✅ Rainfall sufficient
Aug 2.2" 8.7" 0" ✅ Rainfall sufficient
Sep 2.2" 6.9" 0" ✅ Rainfall sufficient
Oct 2.2" 4.5" 0" ✅ Rainfall sufficient
Nov 2.2" 2.5" 0" ✅ Rainfall sufficient
Dec 2.2" 1.8" 0.4" 💧 Light watering

Water needs are for active growing months only (Feb–Dec in Hidalgo 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 ~1,875 GDD — county provides 7,900 GDD Excellent fit

Larkspur Planting Timeline — Progreso, TX

Larkspur Planting Calendar

Activity When Date Range
Bloom January 1 Jan 1 – Mar 12
Fall Sowing October 23 Oct 23 – Nov 6

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

Month-by-Month Timeline

MonthActivities
January Bloom
February Bloom
March Bloom
April
May
June
July
August
September
October Fall Sowing
November Fall Sowing
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 10a

📆 Growing Season

315 days in Hidalgo County

Growing Tips for Larkspur in Progreso

Direct sow Larkspur outdoors after February 06 in Hidalgo County when soil has warmed and frost danger has passed.

With summer highs reaching 100°F in Hidalgo County, provide afternoon shade for Larkspur and water deeply in the morning.

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 →

🌱

Your Hidalgo County Garden Planner — Free

A 22-page printable planner built for Hidalgo County (Zone 10a). 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 Hidalgo County, TX. Local conditions may vary. Last updated: July 2026.