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When to plant Daffodils in New Castle County County,

New Castle County County's spring Daffodils window runs mid-spring through late spring. most warm-season crops establish quickly once soil holds above 60°F. A second sowing from September 26 to October 10 extends the harvest into fall.

When to Plant Daffodils in New Castle County, DE

New Castle County, Delaware Zone 7b June

June to-do list for New Castle County, Delaware

June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in New Castle County, Delaware.

Avg. last frost April 6
Avg. first frost October 31
Soil temp (4") 76°F
Watering Moderate
Pest pressure High
Daylight 14.8 hrs

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Daffodils (Narcissus spp.) are among the most dependable and longest-lived of all spring bulbs. Their cheerful yellow and white blooms emerge in early spring, often while frost is still possible, bringing color weeks before most other flowers. Unlike tulips, established clumps naturalize readily — spreading and returning reliably year after year without replanting. Deer and rodents avoid them due to toxic alkaloids in the bulb and sap, making them a low-maintenance choice for naturalized areas, woodland edges, and mixed borders.

New Castle County, Delaware is in USDA Zone 7b. The average last spring frost is April 6 and the first fall frost is October 31, giving you a growing season of approximately 208 days.

At an elevation of 415 feet, New Castle County receives approximately 38.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Daffodils during the growing season.

Bulb Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting Fragrant
New Castle County, DE (Zone 7b) Long season
208 days
Last Spring Frost April 6
208 growing days
First Fall Frost October 31
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New Castle County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-7.1

Drainage

Well Drained

Daffodils Planting Risk Windows

Early Start (70% safe) ✓ Fits season (218 days to spare)
Transplant: Mar 28 🌸 Bloom: Feb 28 – Mar 21
Recommended (50%) ✓ Fits season (215 days to spare)
Transplant: Apr 6 🌸 Bloom: Mar 9 – Mar 30
Safe Start (90%) ✓ Fits season (203 days to spare)
Transplant: Apr 30 🌸 Bloom: Apr 2 – Apr 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 New Castle County

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

Soil pH

Your soil pH (5.2–7.1) overlaps with Daffodils's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.0%). Annual compost additions will help Daffodils.

How to Plant Daffodils

7"
Planting Depth
7"
Between Plants
8"
Between Rows

Fall planting: Sow 5 weeks before your first frost date for a fall harvest.

Succession Planting Daffodils

12
successive plantings in your 208-day season

Sow every 2.3 weeks. Last sowing by Sep 21 to harvest before frost.

For a dedicated fall crop, sow by Sep 26.

Daffodils Water Budget

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

Monthly Watering Guide for Daffodils

Daffodils 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 Daffodils Needs Rainfall You Supplement Action
Jan 2.4" 0" ❄️ Dormant
Feb 2.7" 0" ❄️ Dormant
Mar 3.4" 0" ❄️ Dormant
Apr 2.2" 3.2" 0" ✅ Rainfall sufficient
May 2.2" 3.3" 0" ✅ Rainfall sufficient
Jun 2.2" 3.3" 0" ✅ Rainfall sufficient
Jul 2.2" 4.1" 0" ✅ Rainfall sufficient
Aug 2.2" 3.2" 0" ✅ Rainfall sufficient
Sep 2.2" 3.1" 0" ✅ Rainfall sufficient
Oct 2.2" 3.2" 0" ✅ Rainfall sufficient
Nov 3.4" 0" ❄️ Dormant
Dec 2.9" 0" ❄️ Dormant

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

Daffodils 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.

Daffodils needs ~502 GDD — county provides 3,484 GDD Excellent fit

Daffodils Planting Timeline — New Castle County, DE

Daffodils Planting Calendar

Activity When Date Range
Bloom August 29 Aug 29 – Sep 19
Fall Sowing September 26 Sep 26 – Oct 10

Plant 7" deep · 7" apart · Rows 8" apart

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

20–40 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7b

📆 Growing Season

208 days in New Castle County

Growing Tips for Daffodils in New Castle County

Direct sow Daffodils outdoors after April 06 in New Castle County when soil has warmed and frost danger has passed.

Your generous 208.0-day season in New Castle County allows multiple plantings of Daffodils. Sow every 10.0 days for continuous harvest.

Common pests for Daffodils in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.

General growing tips

Plant bulbs pointed-end up in fall, 6–8 inches deep and 6–8 inches apart in well-drained soil. Allow 12–16 weeks of cold dormancy for proper vernalization. Do not cut back foliage until it turns yellow (6–8 weeks after bloom) — the dying leaves photosynthesize energy into the bulb for next year. Lift and divide overcrowded clumps every 4–5 years in summer after foliage dies back. In zones 7b–9b, select heat-tolerant cultivars (Jonquilla, Tazetta, and Cyclamineus divisions) that perform better with less chill than large-cupped types. Zones 10+: insufficient winter cold; pre-chilling is required but results inconsistent — not recommended for outdoor culture.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Daffodils in New Castle County, DE?

New Castle County is in Zone 7b with an average last frost of April 6. Plan your Daffodils planting based on this frost date — see the calendar above for exact timing.

What planting zone is New Castle County, DE?

New Castle County, Delaware is in USDA Hardiness Zone 7b. The average last spring frost is April 6 and first fall frost is October 31.

When should I plant Daffodils in New Castle County County, ?

In New Castle County County, , plant Daffodils after the last frost (around April 6) and before the first frost (around October 31). Best results when soil holds above 50°F.

What growing zone is New Castle County County, for Daffodils?

New Castle County County sits in USDA Zone 7b. Daffodils grows reliably in zones 3a through 9b, so it's a good fit here.

Can Daffodils grow in New Castle County County's climate?

Yes — Daffodils grows well in New Castle County County's temperate climate. New Castle County County averages a 208-day frost-free season, with last frost around April 6 and first frost around October 31.

🌱

Your New Castle County Garden Planner — Free

A 22-page printable planner built for New Castle County (Zone 7b). 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 New Castle County, DE. Local conditions may vary. Last updated: June 2026.

Sources & credits

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