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Northumberland County, PA — Planting Guide

Northumberland County is in USDA Zone 6a. The average last spring frost is April 17 and the first fall frost is October 26, giving you a growing season of approximately 192 days.

At an elevation of 324 ft, Northumberland County receives approximately 40.9 in of rainfall annually. Summer highs average 91°F with winter lows around 20°F. The predominant soil type is Silt Loam.

Based on 31 years of NOAA climate station data, the last frost date here varies by 32 days year to year — ranging from April 5 in warm years to May 7 in cold years. The growing season is trending longer by about 0.94 days per decade. Northumberland County scores 70/100 (Good) on the Microclimate Index.

🌡️ Zone

6a (-10°F to -5°F min)

❄️ Last Frost

April 17

🍂 First Frost

October 26

📅 Growing Season

192 days

⛰️ Elevation

324 ft

🌧️ Annual Rainfall

40.9 in

Northumberland County, PA Moderate season
192 days
Last Spring Frost April 17
192 growing days
First Fall Frost October 26

Monthly Watering Calendar

When you'll need to water your garden — based on average monthly rainfall vs. the ~1 inch/week most gardens need.

1"/wk 0" 1.3" 2.5" 3.8" 5" Jan 3.2" Feb 2.8" +0.9" Mar 3.4" +1.1" Apr 3.2" +0.5" May 3.8" Jun 4" +0.5" Jul 3.8" +0.9" Aug 3.4" +1" Sep 3.3" +0.5" Oct 3.8" Nov 2.7" Dec 3.3"
Rainfall sufficient Supplemental water needed Heavy watering required - - - 1"/week garden need
View detailed monthly data
MonthAvg RainfallRainy DaysExtra Water NeededWatering Effort
Jan 3.2 in 11 days None
Feb 2.8 in 9 days None
Mar 3.4 in 12 days 0.9 in Moderate
Apr 3.2 in 10 days 1.1 in Moderate
May 3.8 in 10 days 0.5 in Low
Jun 4 in 12 days 0.3 in Low
Jul 3.8 in 11 days 0.5 in Low
Aug 3.4 in 9 days 0.9 in Moderate
Sep 3.3 in 8 days 1 in Moderate
Oct 3.8 in 9 days 0.5 in Low
Nov 2.7 in 9 days None
Dec 3.3 in 9 days None

Annual total: 40.7 in. Gardens typically need ~1 inch of water per week during the growing season. Months marked "None" for extra water are outside the active growing season for your zone — most gardens are dormant and don't need irrigation during those months.

Northumberland County Soil Profile

Soil Type

Silt Loam

Soil pH

5.1-6.6

Drainage

Well Drained

Frost Risk Probability

Based on 31 years of NOAA weather station data from 3 stations

Too early frost risk Safe to Plant Apr 17 → Oct 26 192 frost-free days Protect crops frost returns Apr May Jun Jul Aug Sep Oct Nov Dec Safe: May 7 Protect by: Nov 7

Beginners: Plant frost-sensitive crops (tomatoes, peppers, squash) after the "Safe" date on the left. Harvest or cover them before the "Protect by" date on the right. Hardy crops (lettuce, peas, kale) can go in the yellow transition zones.

How to read this table: "Conservative" means you're safe from frost 9 out of 10 years — best for beginners and frost-sensitive crops. "Average year" is the typical date. "Aggressive" means only 1 in 10 years is that warm — experienced gardeners with frost protection can try these dates.

Planting Strategy Last Spring Frost First Fall Frost Frost-Free Days
Conservative (safest) May 7 Nov 7 184 days
Cautious Apr 24 Oct 30 189 days
Average year Apr 17 Oct 26 192 days
Optimistic Apr 13 Oct 19 189 days
Aggressive (risky) Apr 5 Oct 12 190 days
📊
How predictable are frost dates here?

Not very — frost dates can vary by ±32 days year-to-year. Use the "Conservative" row in the table below, and keep row covers handy for surprise late frosts.

🌱
Is the growing season changing?

Slightly — seasons are trending a bit longer (0.9 days/decade). Historical frost dates are still reliable for planning.

Gardening Difficulty Score

70 Good
Frost Timing Risk
10.0/10
Drought Risk
3.5/10
Soil Difficulty
1.0/10
Altitude Challenge
0.0/10
Climate Shift
3.8/10
Rainfall Challenge
0.0/10

Northumberland County offers good growing conditions. A little planning around frost dates goes a long way.

Zone 6a Frost Countdown
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Last Frost: Apr 17 First Frost: Oct 26

Local Gardening Help in Northumberland County

Free expert help is closer than you think. Your county's cooperative extension office connects you with trained gardeners, soil testing labs, and local programs — all specific to Northumberland County's climate and soil.

County Extension Office

Northumberland County Penn State Extension Extension Office

Phone: 814-865-4028

Visit Extension Office Website →

Extension offices are run by land-grant universities and funded by the USDA. Their advice is free, research-based, and tailored to your county's specific conditions.

Master Gardener Program

Free gardening help from trained volunteers

Master Gardeners are community volunteers who complete 40–60 hours of university horticultural training. They answer gardening questions, diagnose plant problems, and offer workshops — all free.

Find Master Gardeners in PA →

Many extension offices run a Master Gardener hotline where you can call or email with photos of plant problems for free diagnosis.

Soil Testing

Available through your extension office

Before amending your soil, get it tested. Your extension office offers soil testing (typically $10–$25) that tells you exact pH, nutrient levels, and amendment recommendations specific to what you want to grow.

Request a Soil Test →

Services Available in Northumberland County

Soil testing Pest identification Master Gardener hotline
Finding local nurseries & garden centers in Northumberland County

Why Buy Local

Local nurseries carry plants that are proven to grow in your area. Staff can give you advice specific to Northumberland County's soil and climate that big-box stores can't. Plants from local growers are typically hardier because they're already acclimated to your zone.

How to Find Them

Search for "nurseries near Northumberland County PA" or "garden center Northumberland County" on Google Maps. Also check with your extension office — they often maintain lists of reputable local nurseries and plant sales.

Community gardens & gardening groups

Community gardens are a great way to learn from experienced gardeners in your area, especially if you're limited on space. Search "community garden Northumberland County PA" or check your extension office and local parks department. Facebook groups like "Northumberland County Gardeners" or "Pennsylvania Gardening" are also excellent for local advice and plant swaps.

What to Plant After Your Harvest

After your first crops finish, use the remaining frost-free days to grow a second round.

Show 6 more succession options
After Cauliflower (harvest ends Aug 14) 73 days until frost
After Carrots (harvest ends Jul 24) 94 days until frost
After Watermelon (harvest ends Aug 28) 59 days until frost
After Broccoli (harvest ends Jul 31) 87 days until frost
After Sweet Corn (harvest ends Jul 31) 87 days until frost
After Corn (harvest ends Aug 14) 73 days until frost

Sunlight & Day Length

Monthly daylight hours and peak sun — critical for onion varieties, photoperiod-sensitive plants, and solar garden planning.

Longest Day

14.9 hours

Summer solstice daylight

Shortest Day

9.1 hours

Winter solstice daylight

Peak Sun Hours

8.6 hr/day peak (summer)

Peak sun hours (green dashed line below) account for cloud cover — this is the usable direct sunlight your garden actually receives. Most vegetables need 6+ peak sun hours.

14hr 12hr 2h 6h 9h 13h 16h Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Daylight hours (sunrise to sunset) Peak sun hours (direct sunlight after cloud cover) ▪ Gold zone = long day (14+ hr) ▪ Blue zone = short day (<12 hr)

Onion tip: Your long summer days (14+ hours) support long-day onion varieties like Walla Walla, Sweet Spanish, and Ailsa Craig.

View detailed monthly data
MonthDaylight HoursPeak Sun HoursDay Length
January 9.4 hr 3.7 hr Short day
February 10.4 hr 4.5 hr Short day
March 11.7 hr 5.3 hr Short day
April 13.1 hr 6.2 hr Neutral
May 14.3 hr 7.4 hr Long day
June 14.9 hr 8.6 hr Long day
July 14.7 hr 8.2 hr Long day
August 13.6 hr 7.3 hr Neutral
September 12.3 hr 6.4 hr Neutral
October 10.9 hr 5 hr Short day
November 9.7 hr 3.7 hr Short day
December 9.1 hr 3.3 hr Short day

Peak sun hours factor in typical cloud cover — use these for solar panel and shade-planning calculations.

Soil Temperature & Composting Calendar

Monthly soil temps tell you when to plant warm-season crops, and when your compost pile is actively working.

Plant Warm Crops When

Soil reaches 60°F+

Soil warm enough from May through Oct.

Best Month to Compost

Jun

Microbial activity peaks when soil is warm.

Active Composting

6 months

Solid season. Piles go dormant in winter.

60°F 70°F 20° 40° 60° 80° 100° Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
4" depth 8" depth - - - 60°F (corn, beans) - - - 70°F (tomatoes, peppers)
View detailed monthly data
MonthSoil 4" DeepSoil 8" DeepCompost ActivityTime to Finish
Jan 32°F 39°F ❄️ Dormant ~36 weeks
Feb 32°F 37°F ❄️ Dormant ~36 weeks
Mar 39°F 44°F ❄️ Dormant ~36 weeks
Apr 50°F 50°F 🐢 Slow ~24 weeks
May 63°F 59°F ♻️ Active ~14 weeks
Jun 74°F 70°F 🔥 Peak ~8 weeks
Jul 80°F 77°F 🔥 Peak ~8 weeks
Aug 81°F 78°F 🔥 Peak ~8 weeks
Sep 75°F 74°F 🔥 Peak ~8 weeks
Oct 65°F 67°F ♻️ Active ~14 weeks
Nov 47°F 55°F 🐢 Slow ~24 weeks
Dec 38°F 44°F ❄️ Dormant ~36 weeks

Highlighted rows = soil 60°F+ (safe for warm-season transplants). Compost finishes fastest during peak activity months.

Pest & Disease Pressure in Northumberland County

Computed from local climate patterns — warmer, humid conditions increase pest generations and fungal disease risk.

Insect Pest Pressure

6.4 / 10

Moderate — common pests appear but manageable with monitoring.

Disease Risk

5.7 / 10

Moderate — watch for mildew and blight during wet periods.

Seasonal Risk

Spring Low
Summer High
Fall Low
Winter Low
View 6 common pests in your area
PestRisk LevelPeak Months
Aphids High Apr, May, Jun, Jul, Aug, Sep
Japanese beetles Moderate Jun, Jul, Aug
Squash vine borers Moderate Jun, Jul
Tomato hornworms Moderate Jun, Jul, Aug
Cucumber beetles Low May, Jun, Jul
Stink bugs Low Jun, Jul, Aug, Sep
Organic pest management tips
  • Use row covers on susceptible crops during peak pest months
  • Apply neem oil preventatively every 7-14 days during active pest season
  • Interplant with strong-scented herbs (basil, marigold) to confuse pests
  • Hand-pick larger pests (beetles, caterpillars) in early morning when they're sluggish
  • Practice crop rotation — never plant the same family in the same spot within 3 years

Cover Crops for Northumberland County

Cover crops protect bare soil, fix nitrogen, suppress weeds, and improve soil structure — with county-specific planting dates.

Fall Cover Crops (7 options) — Plant after harvest to protect soil over winter
Crop Plant By Terminate N-Fixing Soil Benefit
Austrian winter peas Aug 28 Apr 3 ✓ Yes Fixes nitrogen, good for heavy clay soils
Crimson clover Aug 20 Apr 3 ✓ Yes Fixes nitrogen, attracts pollinators in spring
Daikon radish Sep 12 Mar 27 Deep taproot breaks compaction, excellent for clay soils
Hairy vetch Aug 15 Apr 3 ✓ Yes Excellent nitrogen fixer, good for depleted soils
Oats Sep 20 Apr 3 Quick biomass, winterkills in cold zones — no spring tillage needed
Winter rye Aug 3 Mar 27 Suppresses weeds, prevents erosion, breaks up compacted soil
Winter wheat Jul 19 Apr 3 Erosion control, weed suppression, good biomass
Spring Cover Crops (3 options) — Build soil before the main growing season
Crop Plant By Terminate N-Fixing Soil Benefit
Buckwheat Apr 26 Aug 24 Rapid growth, attracts pollinators, suppresses weeds
Sorghum-sudan grass Apr 25 Aug 17 Massive biomass, breaks compaction, suppresses nematodes
White clover Mar 17 Aug 24 ✓ Yes Living mulch, fixes nitrogen, permanent ground cover
Summer Cover Crops (1 options) — Fill gaps and suppress weeds between plantings
Crop Plant By Terminate N-Fixing Soil Benefit
Sunflowers May 7 Oct 5 Deep roots break compaction, attract pollinators and beneficial insects

Wind & Microclimate

Wind dries soil, stresses plants, and affects frost patterns. Understanding your exposure helps with garden placement.

Seasonal Wind Speed

Spring: 12 mph   Summer: 8 mph

Fall: 9 mph   Winter: 12 mph

Prevailing wind: W. Moderate wind — consider a temporary windbreak for young seedlings.

Windbreak Benefit

4.9/10

Moderately beneficial — a simple fence or trellis can protect delicate crops from wind stress.

Frost Pocket Risk

Moderate

Some terrain variation (796 ft range). Garden on slopes or higher ground if possible to avoid late-season frost pockets.

Rainwater Harvesting Potential

How much water you can collect, when to collect it, and what size system you need for your garden.

Annual Collection

20,284 gal

Per 1,000 sq ft of roof area (at 80% collection efficiency)

Recommended Setup

6 rain barrels (55 gal each)

For a typical 500 sq ft garden. Serious collectors: consider a 750 gal tank.

Legal Status

Unrestricted

Rainwater harvesting is fully legal in your state with no restrictions.

Best Collection Months

May, Jun, Jul, Oct

Highest rainfall months — your barrels will fill up quickly during these months.

Months to Draw From Storage

Feb, Apr, Nov

Dry months when you'll rely on stored water — size your storage for this gap.

Rainwater collection tips for your area
  • Your county receives approximately 40.7 inches of rain per year
  • A 1,000 sq ft roof can collect roughly 20,284 gallons annually
  • Rainwater harvesting is fully legal in your state
  • Stock up on stored water before your dry season (Feb, Apr, Nov)
  • Use a first-flush diverter to keep roof debris out of your collection

Soil & Growing Conditions in Northumberland County

Soil Type

Silt Loam

Soil pH 5.1–6.6 · Well Drained drainage

Native soil is well-suited to most vegetables and herbs with regular compost additions.

Watering Needs

Drought stress: 3.5/10

Low-to-moderate drought stress. Plan to water 1–2 times per week during peak summer. (40.9 in. annual rainfall)

Season Tips

192-day frost-free season

Plenty of time for warm-season crops. Start heat-lovers indoors 6–8 weeks before last frost to maximise your harvest window.

Free Garden Planner

Plan your entire garden season — organize planting dates, track what you're growing, and know exactly when to start seeds, transplant, and harvest.

Get My Free Planner →

Recommended for Your Garden

🧪
Soil Test Kit $12-25

Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.

📏
Digital pH Meter $10-20

Get instant, accurate soil pH readings to fine-tune your amendments.

🍂
Organic Compost $8-30

Boost soil fertility and structure with rich, well-aged organic compost.

🥬 Vegetables to Grow in Northumberland County

108 vegetables that grow well in Zone 6a with planting dates for Northumberland County.

Show all 108 vegetables with planting dates
Plant Start Indoors Direct Sow Transplant Harvest Days to Maturity
Acorn Squash Mar 13 Apr 24 May 1 Jul 24 – Aug 28 80–100
Amaranth Feb 20 Apr 24 May 1 Jul 31 – Sep 18 90–120
Arugula Mar 13 Apr 3 Apr 17 May 22 – Jul 24 30–50
Asparagus May 1 730–1095
Beets Apr 3 May 29 – Jun 26 50–70
Belgian Endive Mar 13 Apr 3 Apr 17 Aug 7 – Oct 2 110–150
Bitter Melon Feb 20 Apr 24 May 1 Jul 3 – Aug 14 60–90
Black Beans Apr 24 Jul 24 – Sep 11 90–120
Bok Choy Mar 13 Apr 3 Apr 17 May 29 – Jul 3 40–60
Broccoli Mar 13 Apr 3 Apr 17 Jun 19 – Jul 31 60–90
Broccoli Rabe Mar 13 Apr 3 Apr 17 May 29 – Jul 3 40–60
Brussels Sprouts Mar 13 Apr 3 Apr 17 Jul 17 – Sep 11 90–130
Butternut Squash Mar 13 Apr 24 May 1 Jul 31 – Sep 4 85–110
Cabbage Mar 13 Apr 3 Apr 17 Jun 19 – Aug 14 60–100
Calabash Feb 20 Apr 24 May 1 Jul 24 – Sep 18 80–120
Carrots Apr 3 Jun 5 – Jul 10 60–80
Cauliflower Mar 13 Apr 3 Apr 17 Jun 12 – Aug 14 55–100
Celeriac Mar 13 Apr 3 Apr 17 Jul 31 – Sep 4 100–120
Celery Mar 13 Apr 3 Apr 17 Jul 10 – Sep 4 80–120
Celtuce Mar 13 Apr 3 Apr 17 Jun 19 – Jul 31 60–90
Chard Mar 13 Apr 3 Apr 17 Jun 12 – Jul 31 50–60
Chickpeas Mar 13 Apr 3 Apr 17 Jul 10 – Aug 21 80–110
Chicory Mar 13 Apr 3 Apr 17 Jun 19 – Jul 31 60–85
Chinese Cabbage Mar 13 Apr 3 Apr 17 Jun 12 – Jul 10 50–70
Christmas Lima Beans Feb 20 Apr 24 May 1 Jul 24 – Aug 28 80–100
Collard Greens Mar 13 Apr 3 Apr 17 Jun 12 – Aug 14 55–75
Corn Apr 24 Jun 26 – Aug 21 60–100
Cowpeas Apr 24 Jun 26 – Aug 7 60–90
Cress Mar 13 Apr 3 Apr 17 May 1 – May 22 14–21
Crookneck Squash Mar 13 Apr 24 May 1 Jun 19 – Jul 17 45–60
Crosne Apr 3 Sep 4 – Oct 16 150–200
Cucumber Mar 13 Apr 24 May 1 Jun 26 – Aug 21 50–70
Daikon Apr 3 May 29 – Jun 26 50–70
Delicata Squash Mar 13 Apr 24 May 1 Jul 24 – Aug 28 80–100
Edamame Apr 24 Jul 10 – Aug 21 75–100
Eggplant Feb 6 Apr 24 May 1 Jul 10 – Sep 11 65–85
Endive Mar 13 Apr 3 Apr 17 Jun 5 – Jul 10 45–65
Escarole Mar 13 Apr 3 Apr 17 Jun 12 – Jul 10 50–70
Fava Beans Mar 13 Apr 3 Apr 17 Jul 3 – Aug 14 75–100
Fennel Feb 20 Apr 24 May 1 Jul 3 – Aug 14 60–90
Garlic 90–240
Green Beans Apr 24 Jun 19 – Aug 14 50–65
Horseradish May 1 Sep 4 – Nov 13 120–180
Hot Peppers Feb 6 Apr 24 May 1 Jul 10 – Oct 16 70–120
Hubbard Squash Mar 13 Apr 24 May 1 Aug 14 – Sep 18 100–120
Kabocha Mar 13 Apr 24 May 1 Jul 31 – Aug 28 85–100
Kai Lan Mar 13 Apr 3 Apr 17 Jun 5 – Jul 3 45–60
Kale Mar 13 Apr 3 Apr 17 Jun 12 – Aug 7 50–70
Kidney Beans Apr 24 Jul 24 – Aug 28 85–110
Kohlrabi Mar 13 Apr 3 Apr 17 Jun 5 – Jul 10 45–65
Komatsuna Mar 13 Apr 3 Apr 17 May 22 – Jun 26 35–50
Leeks Mar 13 Apr 3 Apr 17 Jul 17 – Oct 2 90–150
Lentils Mar 13 Apr 3 Apr 17 Jul 10 – Aug 21 80–110
Lettuce Mar 13 Apr 3 Apr 17 May 22 – Jul 31 30–60
Lima Beans Apr 24 Jun 26 – Aug 7 60–90
Loofah Feb 20 Apr 24 May 1 Aug 14 – Oct 16 100–150
Luffa Feb 20 Apr 24 May 1 Jul 31 – Oct 16 90–150
Mache Mar 13 Apr 3 Apr 17 May 29 – Jul 3 40–60
Melon Mar 13 Apr 24 May 1 Jul 10 – Aug 28 70–100
Microgreens Mar 13 Apr 3 Apr 17 Apr 24 – May 22 7–21
Mitsuba Mar 13 Apr 3 Apr 10 Jun 5 – Jul 31 50–70
Mizuna Mar 13 Apr 3 Apr 17 May 22 – Jun 19 30–45
Mustard Greens Mar 13 Apr 3 Apr 17 May 22 – Jul 24 30–50
Napa Cabbage Mar 13 Apr 3 Apr 17 Jun 12 – Jul 17 55–75
New Zealand Spinach Feb 20 Apr 24 May 1 Jun 26 – Jul 24 55–70
Okra Feb 20 Apr 24 May 1 Jun 26 – Aug 21 50–65
Onion Mar 13 Apr 3 Apr 17 Jul 17 – Sep 4 90–120
Pac Choi Mar 13 Apr 3 Apr 17 May 29 – Jun 26 40–55
Parsnip Apr 3 Jul 17 – Aug 28 100–130
Patty Pan Squash Mar 13 Apr 24 May 1 Jun 19 – Jul 17 45–60
Peas Mar 13 Apr 3 Apr 17 Jun 12 – Aug 7 55–70
Peppers Feb 6 Apr 24 May 1 Jul 3 – Sep 11 60–90
Pole Beans Feb 20 Apr 24 May 1 Jun 26 – Aug 21 55–70
Potatoes Feb 20 Apr 24 May 1 Jul 10 – Sep 18 70–120
Pumpkin Mar 13 Apr 24 May 1 Jul 31 – Sep 18 85–120
Purslane Mar 13 Apr 3 Apr 17 May 29 – Jul 3 40–60
Radicchio Mar 13 Apr 3 Apr 17 Jun 19 – Jul 24 60–80
Radish Apr 3 May 1 – May 22 22–35
Rhubarb May 8 365–730
Romanesco Mar 13 Apr 3 Apr 17 Jul 3 – Aug 14 75–100
Rutabaga Apr 3 Jun 26 – Jul 31 80–100
Salsify Apr 3 Jul 17 – Aug 28 100–130
Savoy Cabbage Mar 13 Apr 3 Apr 17 Jun 26 – Aug 21 70–110
Scallions Mar 13 Apr 3 Apr 17 Jun 12 – Jul 10 50–70
Scarlet Runner Beans Feb 20 Apr 24 May 1 Jul 3 – Aug 7 60–80
Shallot Mar 13 Apr 3 Apr 17 Jul 17 – Sep 4 90–120
Shiso Feb 27 Apr 24 May 1 Jun 26 – Aug 21 50–70
Snap Peas Feb 20 Apr 24 May 1 Jun 26 – Aug 21 55–70
Snow Peas Mar 13 Apr 3 Apr 17 Jun 12 – Aug 7 50–65
Soybeans Apr 24 Jul 17 – Sep 11 80–120
Spaghetti Squash Mar 13 Apr 24 May 1 Jul 31 – Aug 28 85–100
Spinach Mar 13 Apr 3 Apr 17 May 22 – Jul 24 35–50
Squash (Summer) Mar 13 Apr 24 May 1 Jun 19 – Aug 21 45–65
Squash (Winter) Mar 13 Apr 24 May 1 Jul 24 – Sep 18 80–120
Sunchoke May 1 Aug 21 – Oct 16 110–150
Sunflower Feb 20 Apr 24 May 1 Jul 10 – Aug 28 70–100
Sweet Corn Apr 24 Jun 26 – Aug 7 60–90
Sweet Potatoes Feb 20 Apr 24 May 1 Jul 31 – Sep 18 90–120
Tatsoi Mar 13 Apr 3 Apr 17 May 22 – Jun 26 35–50
Tomatillo Feb 20 Apr 24 May 1 Jul 3 – Sep 11 60–85
Tomatoes Feb 20 Apr 24 May 1 Jul 3 – Sep 11 60–85
Turnip Apr 3 May 15 – Jun 19 40–60
Watercress Mar 13 Apr 3 Apr 17 May 29 – Jul 3 40–60
Watermelon Mar 13 Apr 24 May 1 Jul 10 – Aug 28 70–100
Wax Beans Apr 24 Jun 19 – Aug 14 50–65
Winter Melon Feb 20 Apr 24 May 1 Jul 31 – Sep 18 90–120
Yard Long Beans Feb 20 Apr 24 May 1 Jun 26 – Aug 7 55–80
Zucchini Mar 13 Apr 24 May 1 Jun 19 – Aug 14 45–60

🍓 Fruits to Grow in Northumberland County

27 fruits that grow well in Zone 6a with planting dates for Northumberland County.

Show all 27 fruits with planting dates
Plant Start Indoors Direct Sow Transplant Harvest Days to Maturity
Alpine Strawberries May 8 Aug 7 – Nov 20 90–180
Aronia May 8 730–1095
Blackberries May 8 365–730
Blueberries May 8 730–1095
Boysenberries May 8 365–730
Cantaloupe May 8 Jul 17 – Aug 21 70–90
Che Fruit May 8 1095–1825
Cranberries May 8 730–1095
Currants May 8 730–1095
Elderberries May 8 730–1095
Goji Berries May 8 730–1095
Gooseberries May 8 730–1095
Grapes May 8 730–1095
Ground Cherry May 8 Jul 17 – Sep 11 65–80
Hardy Kiwi May 8 1095–1825
Haskaps May 8 730–1095
Honeydew May 8 Jul 31 – Sep 11 80–110
Jostaberry May 8 730–1095
Lingonberries May 8 730–1095
Medlar May 8 1095–1825
Mulberries May 8 730–1825
Pawpaw May 8 1095–2555
Persimmon May 8 1095–2555
Quince May 8 1095–1825
Raspberries May 8 365–730
Serviceberries May 8 730–1095
Strawberries May 8 Aug 7 – Nov 20 90–365

🌿 Herbs to Grow in Northumberland County

38 herbs that grow well in Zone 6a with planting dates for Northumberland County.

Show all 38 herbs with planting dates
Plant Start Indoors Direct Sow Transplant Harvest Days to Maturity
Angelica Mar 13 Apr 3 Apr 10 365–730
Anise Mar 13 Apr 3 Apr 10 Jul 10 – Sep 25 90–120
Basil Feb 27 Apr 24 May 1 Jun 26 – Aug 28 50–75
Bee Balm Apr 24 Jul 24 – Oct 9 90–120
Borage Mar 13 Apr 3 Apr 10 Jun 5 – Jul 24 50–60
Caraway Mar 13 Apr 3 Apr 10 365–450
Catnip Apr 24 Jun 26 – Aug 28 60–80
Chamomile Mar 13 Apr 3 Apr 10 Jun 12 – Aug 21 60–90
Chervil Mar 13 Apr 3 Apr 10 May 22 – Jul 24 40–60
Chives Apr 24 Jun 26 – Sep 4 60–90
Cilantro Mar 13 Apr 3 Apr 10 May 22 – Jul 24 40–60
Comfrey Apr 24 Jun 26 – Sep 4 60–90
Cumin Mar 13 Apr 3 Apr 10 Jul 24 – Sep 25 100–120
Dill Mar 13 Apr 3 Apr 10 May 22 – Jul 24 40–60
Echinacea Apr 24 Aug 28 – Nov 6 120–180
Epazote Feb 27 Apr 24 May 1 Jun 19 – Aug 14 45–60
Fennel (herb) Mar 13 Apr 3 Apr 10 Jun 12 – Aug 21 60–90
Feverfew Apr 24 Jul 24 – Oct 9 90–120
Garlic Chives Apr 24 Jun 26 – Sep 4 60–90
Horehound Apr 24 Jul 10 – Sep 4 75–90
Hyssop Apr 24 Jul 3 – Sep 4 70–90
Lavender Apr 24 Jul 24 – Nov 6 90–200
Lemon Balm Apr 24 Jun 26 – Aug 14 60–70
Lemon Thyme Apr 24 Jul 3 – Sep 4 70–90
Lovage Apr 24 Jul 3 – Sep 4 70–90
Marjoram Apr 24 Jun 26 – Sep 4 60–90
Mint Apr 24 Jun 26 – Sep 4 60–90
Oregano Apr 24 Jun 26 – Sep 4 60–90
Parsley Mar 13 Apr 3 Apr 10 Jun 12 – Aug 14 60–80
Rue Apr 24 Jul 3 – Sep 4 70–90
Sage Apr 24 Jul 10 – Sep 4 75–90
Savory Apr 24 Jun 19 – Aug 14 50–70
Sorrel Mar 13 Apr 3 Apr 10 May 22 – Jul 24 40–60
Tarragon Apr 24 Jun 26 – Sep 4 60–90
Thai Basil Feb 27 Apr 24 May 1 Jun 26 – Aug 28 50–75
Thyme Apr 24 Jul 3 – Sep 4 70–90
Valerian Apr 24 Aug 28 – Nov 6 120–180
Yarrow Apr 24 Jul 24 – Oct 9 90–120

Monthly Planting Guide for Northumberland County

Gardening Guides & Resources

Helpful guides from The Ultimate Homestead to improve your garden in Northumberland County.

Frequently Asked Questions

What planting zone is Northumberland County, PA?

Northumberland County is in USDA Hardiness Zone 6a. This zone classification determines which perennial plants survive winter and sets the baseline for frost timing across the county.

When is the last frost in Northumberland County, PA?

Based on 31 years of NOAA weather station data, the median last spring frost in Northumberland County falls around April 17. In 8 out of 10 years, last frost lands between April 5 and May 7 — a 32-day window of variability. Use May 7 as your conservative safe-to-plant date for frost-sensitive crops.

When is the first fall frost in Northumberland County, PA?

The median first fall frost in Northumberland County arrives around October 26. In cold years it can arrive as early as October 12; in mild years as late as November 7. Harvest or protect frost-sensitive crops — tomatoes, peppers, basil, squash — before this date.

How long is the growing season in Northumberland County?

Northumberland County has a frost-free growing season of approximately 192 days. This is enough time for most warm-season crops including tomatoes, peppers, and squash with proper timing. Climate records show the growing season is trending longer by about 0.94 days per decade.

What is the soil like in Northumberland County for gardening?

Northumberland County has predominantly Silt Loam soil with a pH range of 5.1–6.6 and Well Drained drainage. Most vegetables and herbs grow well with standard composting and seasonal soil amendment.

What is grown commercially in Northumberland County?

Northumberland County has commercial agriculture that includes Dairy, Hay, Corn, Apples, Sweet Corn. These crops reflect the local climate and soil conditions — what succeeds commercially often translates well to home gardens in the same area.

Is Northumberland County a good location for home gardening?

Northumberland County scores 70/100 (Good) on our Microclimate Index, which combines frost reliability, drought pressure, soil challenge, elevation risk, and long-term climate trend. This is an above-average location for home gardening with relatively predictable growing conditions.

🌱

Plan Your Garden with Confidence

Get our free Garden Planner — designed to help Northumberland County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Level Up Your Garden

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA GHCN-D daily station data (1994–2024) from 3 weather stations in or near Northumberland County (31 years of records). Frost dates represent 50% probability averages; local conditions vary by elevation and microclimate. Last updated: April 2026.