What Planting Zone is Delaware?[Map, Cities, and Growing Tips]
If you’re planning a garden in Delaware, one of the most important things to know is your planting zone. The USDA Plant Hardiness Zone Map helps gardeners figure out which plants will thrive year-round in their region. But what planting zone is Delaware exactly?
In this guide, we’ll answer that question in detail — breaking it down by region, listing major cities, explaining the climate, and sharing practical tips so you can make the most of Delaware’s growing conditions.
🌱 What Planting Zone is Delaware?
Delaware falls across USDA Zones 7a and 7b. While it’s a small state, these subtle differences in planting zones matter more than you might think.
| Region | USDA Planting Zone |
|---|---|
| Northern Delaware (Wilmington, Newark) | Zone 7a |
| Central Delaware (Dover, Smyrna) | Zone 7b |
| Southern Delaware (Rehoboth, Georgetown) | Zone 7b |
So, what planting zone is Delaware? For most gardeners, it’s Zone 7 — either 7a or 7b — meaning average minimum winter temperatures range between 0°F and 10°F. That allows for a relatively long growing season and supports a wide range of annuals, perennials, shrubs, and vegetables.
📍 What Planting Zone is Delaware By City?
Here’s a breakdown of common cities in Delaware and their USDA planting zones:
| City | Planting Zone |
|---|---|
| Wilmington | Zone 7a |
| Newark | Zone 7a |
| Dover | Zone 7b |
| Middletown | Zone 7a |
| Smyrna | Zone 7b |
| Milford | Zone 7b |
| Rehoboth Beach | Zone 7b |
| Seaford | Zone 7b |
| Georgetown | Zone 7b |
Although the entire state is in Zone 7, what planting zone is Delaware in your area may shift slightly based on microclimates — especially near water or in low-lying inland areas.
🌡️ Why Knowing What Planting Zone is Delaware Matters?
Knowing what planting zone is Delaware helps you select the right plants for your location, especially when it comes to perennials, trees, and shrubs that must survive cold winters. For example:
- Zone 7a plants can tolerate temps down to 0°F
- Zone 7b plants can tolerate temps down to 5–10°F
If you choose a tropical plant not suited to Zone 7, it might not make it through the winter. On the other hand, plants meant for Zones 3–5 might not thrive because Delaware’s winters are too mild to trigger certain growth cycles.
🧠 Gardening Example: Tomatoes in Delaware
Tomatoes love warm soil and full sun, and they thrive in Delaware’s planting zones. In Zone 7a (Wilmington), tomato seeds should be started indoors around late February, and outdoor planting should wait until mid-April to early May.
In Zone 7b (Rehoboth or Dover), you might be able to plant a little earlier, depending on frost dates.
Knowing what planting zone is Delaware makes it easier to plan your sowing calendar, especially for:
- Tomatoes
- Peppers
- Eggplants
- Cucumbers
- Squash
📅 When to Plant in Delaware?
Your planting zone affects your first and last frost dates, which determines when to plant different crops:
| Plant Type | Zone 7a Start | Zone 7b Start |
|---|---|---|
| Cool-season veggies (lettuce, spinach) | March | Late February |
| Warm-season crops (tomatoes, beans) | Late April | Mid-April |
| Perennials & shrubs | Fall or Early Spring | Fall or Early Spring |
Because the entire state shares Zone 7, you can confidently follow Delaware-wide planting guides — just shift by a week or two depending on your city.
💡 Tips for Gardening in Delaware’s Planting Zones
Delaware has a humid subtropical climate, which means hot, wet summers and fairly mild winters. But frost still happens — and that’s why knowing what planting zone is Delaware makes a real difference.
🌿 Smart Gardening Tips:
- Use raised beds in spring to warm the soil faster
- Watch for late frosts in Zone 7a
- Choose disease-resistant varieties in humid months
- Mulch heavily to retain soil moisture and block weeds
Delaware’s planting zone allows for a robust growing season, especially if you plan with frost dates and zone guidelines in mind.
📍 What Planting Zone is Delaware in Your Zip Code?
If you want the most accurate result, go beyond city names and search by zip code. Microclimates in Delaware (especially near the ocean or the Chesapeake Bay) can slightly affect your zone classification.
Check the official USDA Plant Hardiness Zone Map to look up your exact planting zone by zip code. This is the best way to settle the question: what planting zone is Delaware where I live?
🧮 Recommended Gardening Tools for Delaware
Make gardening easier with these free tools:
- Soil Volume Calculator – Know exactly how much soil you need for raised beds.
- Plant Spacing Calculator – Prevent overcrowding and maximize yield.
- Indoor Plant Watering Calculator – Perfect for your houseplants or container garden.
These tools are especially useful if you’re gardening within Delaware’s planting zones, where timing and spacing can make or break your success.
🙋 FAQs About Delaware Planting Zones
What planting zone is Delaware for fruit trees?
Most of Delaware falls under Zone 7, which is suitable for apples, pears, peaches, and cherries. Choose cold-hardy varieties for northern parts, and heat-tolerant types in southern Delaware.
When is the last frost in Delaware?
- Zone 7a (Wilmington): Around April 15
- Zone 7b (Dover, southern DE): Around April 5
Always check the 10-day forecast before planting outside.
✅ Final Thoughts: What Planting Zone is Delaware?
So, what planting zone is Delaware? It’s mostly Zone 7a and 7b, making it a great place for both vegetables and ornamentals — as long as you follow frost dates and choose plants suited to your region.
Knowing your USDA zone helps you:
- Pick the right perennials
- Time your planting windows
- Avoid unnecessary losses due to cold snaps
Now that you know what planting zone is Delaware, you can plant with confidence — and grow with success.
