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When to Plant Salvia in Waller County, TX

Waller County, Texas Zone 9a June

Waller County, Texas gardeners: here's your June plan

We've pulled the most time-sensitive tasks for Waller County, Texas this June and put them front and centre. Tackle them in order.

Avg. last frost February 19
Avg. first frost December 4
Soil temp (4") 81°F
Watering Low
Pest pressure High
Daylight 13.9 hrs
  1. Start harvesting salvia

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

July prep starts now
  • First harvests: salvia

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Salvia splendens is a tender perennial from Brazil grown as a warm-season annual throughout the US. Its vivid, upright flower spikes in brilliant red, purple, and coral are irresistible to hummingbirds, bees, and butterflies. One of the longest-blooming annuals in the landscape — plants bloom from early summer until hard frost with minimal deadheading required.

Waller County, Texas is in USDA Zone 9a. The average last spring frost is February 19 and the first fall frost is December 4, giving you a growing season of approximately 288 days.

At an elevation of 376 feet, Waller County receives approximately 64.1 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 95°F, so Salvia may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Salvia will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Salvia root diseases.

Annual Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting Fragrant
Waller County, TX (Zone 9a) Year-round
288 days
Last Spring Frost February 19
288 growing days
First Fall Frost December 4

Waller County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.6-6.2

Drainage

Well Drained

Salvia Planting Risk Windows

Early Start (70% safe) ✓ Fits season (69 days to spare)
Start indoors: Dec 17 Transplant: Jan 21 🌸 Bloom: Apr 1 – Sep 16
Recommended (50%) ✓ Fits season (71 days to spare)
Start indoors: Dec 25 Transplant: Jan 29 🌸 Bloom: Apr 9 – Sep 24
Safe Start (90%) ✓ Fits season (70 days to spare)
Start indoors: Jan 12 Transplant: Feb 16 🌸 Bloom: Apr 27 – Oct 12

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 Waller County

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

Soil pH

Your soil pH (5.6–6.2) is within Salvia's preferred range (5.5–7.0).

Soil Texture

Sandy soil in Waller County warms quickly in spring but drains fast. Salvia will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is moderate (2.0%). Annual compost additions will help Salvia.

How to Plant Salvia

12"
Between Plants
18"
Between Rows

Succession Planting Salvia

4
successive plantings in your 288-day season

Sow every 8 weeks. Last sowing by Sep 05 to harvest before frost.

Salvia Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 176 gal / 100 sq ft

Monthly Watering Guide for Salvia

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

Month Salvia Needs Rainfall You Supplement Action
Jan 1.7" 0" ❄️ Dormant
Feb 4.3" 2.4" 1.9" 💧 Light watering
Mar 4.3" 4.6" 0" ✅ Rainfall sufficient
Apr 4.3" 7.3" 0" ✅ Rainfall sufficient
May 4.3" 8.9" 0" ✅ Rainfall sufficient
Jun 4.3" 9.1" 0" ✅ Rainfall sufficient
Jul 4.3" 7.9" 0" ✅ Rainfall sufficient
Aug 4.3" 7" 0" ✅ Rainfall sufficient
Sep 4.3" 6.9" 0" ✅ Rainfall sufficient
Oct 4.3" 4.3" 0" ✅ Rainfall sufficient
Nov 4.3" 2.2" 2.1" 💧 Light watering
Dec 4.3" 1.7" 2.6" 🚿 Regular watering

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

Salvia 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.

Salvia needs ~1,700 GDD — county provides 6,141 GDD Excellent fit

Salvia Planting Timeline — Waller County, TX

Salvia Planting Calendar

Activity When Date Range
Start Indoors December 25 Dec 25 – Jan 8
Transplant Outdoors January 29 Jan 29 – Feb 12
Bloom April 9 Apr 9 – Sep 24

· 12" apart · Rows 18" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 5.5–7 · Your soil: ideal

🗺️ USDA Zone

Zone 9a

📆 Growing Season

288 days in Waller County

Growing Tips for Salvia in Waller County

Direct sow Salvia outdoors after February 19 in Waller County when soil has warmed and frost danger has passed.

Sandy soil in Waller County dries quickly — mulch Salvia with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

General growing tips

Start indoors 8-10 weeks before last frost; seeds need 65-70°F soil and light to germinate (surface-sow, do not cover). Transplant after last frost when soil has warmed. Salvia is frost-sensitive — even a light frost kills plants. Pinch spent spikes to encourage continued bloom. Tolerates heat and humidity well once established. In zones 9b-11b can be grown as a short-lived perennial.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Salvia in Waller County, TX?

Waller County is in Zone 9a with an average last frost of February 19. Plan your Salvia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Waller County, TX?

Waller County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 19 and first fall frost is December 4.

🌱

Your Waller County Garden Planner — Free

A 22-page printable planner built for Waller County (Zone 9a). 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 Waller County, TX. 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.