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When to plant Nasturtium in St. Johns County County,

For St. Johns County County, gardeners: plant Nasturtium January 12 through February 2 once soil reads 50°F.

When to Plant Nasturtium in St. Johns County, FL

St. Johns County, Florida Zone 9b June

Your June game plan for St. Johns County, Florida

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

Avg. last frost February 9
Avg. first frost December 2
Soil temp (4") 86°F
Watering Low
Pest pressure High
Daylight 13.9 hrs
  1. Bring in the nasturtium

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

Before July arrives, get these ready
  • First harvests: nasturtium

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Nasturtium (Tropaeolum majus) is a fast-growing annual with distinctive round, lily-pad leaves and bold trumpet-shaped blooms in warm oranges, reds, and yellows. Both the flowers and leaves are edible with a peppery watercress flavor. Planted near vegetables, nasturtiums act as a sacrifice trap-crop, luring aphids away from more valuable plants. They thrive in poor, dry soil — rich conditions produce lush foliage but few flowers.

St. Johns County, Florida is in USDA Zone 9b. The average last spring frost is February 9 and the first fall frost is December 2, giving you a growing season of approximately 296 days.

At an elevation of 57 feet, St. Johns County receives approximately 51.1 inches of rainfall annually with predominantly sand soil. Summer highs average 99°F, so Nasturtium may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Nasturtium will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Nasturtium root diseases.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
St. Johns County, FL (Zone 9b) Year-round
296 days
Last Spring Frost February 9
296 growing days
First Fall Frost December 2
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St. Johns County Soil Profile

Soil Type

Sand

Soil pH

4.9-6.1

Drainage

Well Drained

Nasturtium Planting Risk Windows

Early Start (70% safe) ✓ Fits season (83 days to spare)
Start indoors: Dec 28 Transplant: Dec 28 🌸 Bloom: Feb 22 – Sep 6
Recommended (50%) ✓ Fits season (72 days to spare)
Start indoors: Jan 12 Transplant: Jan 12 🌸 Bloom: Mar 9 – Sep 21
Safe Start (90%) ✓ Fits season (63 days to spare)
Start indoors: Feb 11 Transplant: Feb 11 🌸 Bloom: Apr 8 – Oct 21

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 St. Johns County

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

Soil pH

Your soil pH (4.9–6.1) is more acidic than Nasturtium prefers (6.0–8.0). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is low (1.5%). Add 2-3 inches of compost before planting Nasturtium.

How to Plant Nasturtium

0.5"
Planting Depth
10"
Between Plants
12"
Between Rows

Succession Planting Nasturtium

6
successive plantings in your 296-day season

Sow every 6.3 weeks. Last sowing by Sep 28 to harvest before frost.

Nasturtium Water Budget

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

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

Monthly Watering Guide for Nasturtium

Nasturtium 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 Nasturtium Needs Rainfall You Supplement Action
Jan 2.4" 0" ❄️ Dormant
Feb 2.2" 2.4" 0" ✅ Rainfall sufficient
Mar 2.2" 2.8" 0" ✅ Rainfall sufficient
Apr 2.2" 2.8" 0" ✅ Rainfall sufficient
May 2.2" 3.5" 0" ✅ Rainfall sufficient
Jun 2.2" 7" 0" ✅ Rainfall sufficient
Jul 2.2" 7.1" 0" ✅ Rainfall sufficient
Aug 2.2" 7.6" 0" ✅ Rainfall sufficient
Sep 2.2" 6.9" 0" ✅ Rainfall sufficient
Oct 2.2" 4.3" 0" ✅ Rainfall sufficient
Nov 2.2" 2.1" 0.1" 💧 Light watering
Dec 2.2" 2.3" 0" ✅ Rainfall sufficient

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

Nasturtium 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.

Nasturtium needs ~1,455 GDD — county provides 7,202 GDD Excellent fit

Nasturtium Planting Timeline — St. Johns County, FL

Nasturtium Planting Calendar

Activity When Date Range
Start Indoors January 12 Jan 12 – Jan 26
Transplant Outdoors January 12 Jan 12 – Jan 26
Direct Sow January 12 Jan 12 – Feb 2
Bloom March 9 Mar 9 – Sep 21

Plant 0.5" deep · 10" apart · Rows 12" apart

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

55–65 days

🧪 Soil pH

Needs 6–8 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9b

📆 Growing Season

296 days in St. Johns County

Growing Tips for Nasturtium in St. Johns County

Direct sow Nasturtium outdoors after February 09 in St. Johns County when soil has warmed and frost danger has passed.

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

With summer highs reaching 99°F in St. Johns County, provide afternoon shade for Nasturtium and water deeply in the morning.

General growing tips

Direct-sow large seeds 1/2 inch deep after last frost; soak seeds overnight to speed germination (7-10 days). Nasturtiums dislike root disturbance so direct sowing is strongly preferred. Avoid fertilizing — poor soil brings the best bloom. Trailing types can cover banks and climb trellises; dwarf types suit containers. In hot climates (zones 9+) plant in fall for winter/spring bloom as plants struggle in peak summer heat.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Nasturtium in St. Johns County, FL?

St. Johns County is in Zone 9b with an average last frost of February 9. Plan your Nasturtium planting based on this frost date — see the calendar above for exact timing.

What planting zone is St. Johns County, FL?

St. Johns County, Florida is in USDA Hardiness Zone 9b. The average last spring frost is February 9 and first fall frost is December 2.

When should I plant Nasturtium in St. Johns County, ?

In St. Johns County, , plant Nasturtium after the last frost (around February 9) and before the first frost (around December 2). Best results when soil holds above 50°F.

What growing zone is St. Johns County, for Nasturtium?

St. Johns County sits in USDA Zone 9b. Nasturtium grows reliably in zones 2a through 11b, so it's a good fit here.

Can Nasturtium grow in St. Johns County's climate?

Yes — Nasturtium grows well in St. Johns County's temperate climate. St. Johns County averages a 297-day frost-free season, with last frost around February 9 and first frost around December 2.

🌱

Your St. Johns County Garden Planner — Free

A 22-page printable planner built for St. Johns County (Zone 9b). 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 St. Johns County, FL. 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.