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When to Plant Calendula in Castleton, VT

Rutland County, Vermont Zone 5a June

Your June game plan for Rutland County, Vermont

Your Rutland County, Vermont garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.

Avg. last frost May 9
Avg. first frost October 7
Soil temp (4") 66°F
Watering Low
Pest pressure High
Daylight 15.2 hrs
  1. Begin indoor sowing: calendula

    Give them 6–8 weeks indoors before the last frost and you'll transplant into warm soil with seedlings that are already leaping.

  2. Pick calendula

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

Looking ahead to July
  • First harvests: calendula

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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.

Castleton, Vermont is in USDA Zone 5a. The average last spring frost is May 9 and the first fall frost is October 7, giving you a growing season of approximately 151 days.

At an elevation of 477 feet, Rutland County receives approximately 41.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°F, so choose short-season varieties of Calendula to ensure they mature before fall.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Castleton, VT (Zone 5a) Moderate season
151 days
Last Spring Frost May 9
151 growing days
First Fall Frost October 7

Castleton Soil Profile

Soil Type

Silt Loam

Soil pH

5.1-6.3

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (20 days to spare)
Start indoors: Mar 23 Transplant: May 4 🌸 Bloom: Jun 22 – Sep 14
Recommended (50%) ✓ Fits season (18 days to spare)
Start indoors: Mar 28 Transplant: May 9 🌸 Bloom: Jun 27 – Sep 19
Safe Start (90%) ✓ Fits season (20 days to spare)
Start indoors: Apr 8 Transplant: May 20 🌸 Bloom: Jul 8 – Sep 30

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 Castleton

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

Soil pH

Your soil pH (5.1–6.3) overlaps with Calendula's range (5.5–7.0), though not a perfect match.

Soil Texture

The silt loam soil in Rutland County is excellent for Calendula — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.7%). Annual compost additions will help Calendula.

How to Plant Calendula

0.3"
Planting Depth
9"
Between Plants
12"
Between Rows

Succession Planting Calendula

3
successive plantings in your 151-day season

Sow every 5.7 weeks. Last sowing by Jul 29 to harvest before frost.

Calendula Water Budget

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

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 3.1" 0" ❄️ Dormant
Feb 2.4" 0" ❄️ Dormant
Mar 3.6" 0" ❄️ Dormant
Apr 3.7" 0" ❄️ Dormant
May 2.2" 3.9" 0" ✅ Rainfall sufficient
Jun 2.2" 4.1" 0" ✅ Rainfall sufficient
Jul 2.2" 4" 0" ✅ Rainfall sufficient
Aug 2.2" 3.5" 0" ✅ Rainfall sufficient
Sep 2.2" 3.8" 0" ✅ Rainfall sufficient
Oct 2.2" 3" 0" ✅ Rainfall sufficient
Nov 3.4" 0" ❄️ Dormant
Dec 3.3" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Rutland 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 needs ~645 GDD — county provides 1,623 GDD Excellent fit

Calendula Planting Timeline — Castleton, VT

Calendula Planting Calendar

Activity When Date Range
Start Indoors March 28 Mar 28 – Apr 11
Transplant Outdoors May 9 May 9 – May 23
Direct Sow April 18 Apr 18 – May 9
Bloom June 27 Jun 27 – Sep 19

Plant 0.3" deep · 9" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors Direct Sow
May Transplant Outdoors Direct Sow
June Bloom
July Bloom
August Bloom
September Bloom
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: acceptable

🗺️ USDA Zone

Zone 5a

📆 Growing Season

151 days in Rutland County

Growing Tips for Calendula in Castleton

Direct sow Calendula outdoors after May 09 in Rutland County when soil has warmed and frost danger has passed.

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 →

🌱

Your Rutland County Garden Planner — Free

A 22-page printable planner built for Rutland 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 Rutland County, VT. Local conditions may vary. Last updated: June 2026.