When to Plant Calendula in Guadalupe County, TX
What to do in June
Here's what deserves your attention in Guadalupe County, Texas this month. Everything below is tailored to Zone 9a and timed around your local frost dates.
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Bring in the calendula
This is the payoff month. Bring a basket, bring a friend, and get into the beds.
A few tasks this June that'll pay off in July
- First harvests: calendula
Calendula (Calendula officinalis) is a cheerful, edible-flowered cool-season annual valued by herbalists, chefs, and gardeners alike. Its golden-orange petals are used in salves, teas, and as a saffron substitute. Hardy enough to tolerate light frosts, it blooms prolifically in spring and fall, taking a pause during the hottest weeks of summer.
Guadalupe County, Texas is in USDA Zone 9a. The average last spring frost is March 7 and the first fall frost is November 21, giving you a growing season of approximately 259 days.
At an elevation of 3,679 feet, Guadalupe County receives approximately 63 inches of rainfall annually with predominantly clay soil. Summer highs average 93°F, providing good warmth for Calendula during the growing season. Clay soil retains moisture well for Calendula, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Calendula root diseases.
Guadalupe County Soil Profile
Soil Type
Clay
Soil pH
6.9-8.2
Drainage
Well Drained
Calendula Planting Risk Windows
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 Guadalupe County
How your county's soil matches Calendula's growing requirements.
Soil pH
Your soil pH (6.9–8.2) is more alkaline than Calendula prefers (5.5–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
Your clay soil in Guadalupe County is workable for Calendula. Add compost annually to improve structure.
Organic Matter
Organic matter is moderate (2.7%). Annual compost additions will help Calendula.
How to Plant Calendula
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Calendula
Sow every 5.7 weeks. Last sowing by Sep 12 to harvest before frost.
For a dedicated fall crop, sow by Aug 29.
Calendula Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Calendula
Calendula 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 | Calendula Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 2.1" | 0" | ❄️ Dormant |
| Mar | 2.2" | 4.4" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 6.5" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 9.5" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 9.3" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 8" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 7.1" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 6.4" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 1.9" | 0.3" | 💧 Light watering |
| Dec | — | 1.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Guadalupe County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Calendula 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.
Calendula Planting Timeline — Guadalupe County, TX
Calendula Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | February 7 | Feb 7 – Feb 21 |
| Direct Sow | January 10 | Jan 10 – Jan 31 |
| Bloom | March 21 | Mar 21 – Jul 25 |
| Fall Sowing | August 29 | Aug 29 – Sep 12 |
Plant 0.3" deep · 9" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Direct Sow |
| February | Transplant Outdoors |
| March | Bloom |
| April | Bloom |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 5.5–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 9a
📆 Growing Season
259 days in Guadalupe County
Growing Tips for Calendula in Guadalupe County
Direct sow Calendula outdoors after March 07 in Guadalupe County when soil has warmed and frost danger has passed.
With Guadalupe County's clay soil (40% clay), work in 3-4 inches of compost before planting Calendula. Avoid tilling when soil is wet to prevent compaction.
Common pests for Calendula in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct-sow in early spring as soon as soil can be worked — seeds germinate in cool soil (50-65°F). In zones 7+, also sow in fall for winter/spring bloom. Deadhead consistently to extend bloom. Plants self-seed readily; save a few spent heads and allow them to drop. Harvest petals when flowers are fully open for best flavor and medicinal value.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Calendula in Other Locations
Frequently Asked Questions
When should I plant Calendula in Guadalupe County, TX?
Guadalupe County is in Zone 9a with an average last frost of March 7. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.
What planting zone is Guadalupe County, TX?
Guadalupe County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is March 7 and first fall frost is November 21.
Your Guadalupe County Garden Planner — Free
A 22-page printable planner built for Guadalupe 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.