Knowing when to plant vegetables in Pennsylvania is the first step to a successful harvest. Our state’s varied climate means timing is everything, and this guide will help you get it right.
Pennsylvania spans USDA Hardiness Zones 5b to 7a, which means frost dates can vary by weeks. A late frost can wipe out tender seedlings, while planting to late can mean your crops won’t mature before fall. Let’s break down the schedule so you can plant with confidence.
When To Plant Vegetables In Pennsylvania
This schedule is based on average last spring frost dates, which range from early May in the north and mountains to mid-April in southeastern PA. Always check your local frost dates for the best accuracy.
Early Spring (As soon as soil can be worked)
These cold-hardy crops can be sown directly in the garden 4-6 weeks before your last frost. The soil should be thawed and not soggy.
- Peas
- Spinach
- Kale
- Lettuce & Arugula
- Radishes
- Carrots
- Beets
- Potatoes (plant whole or cut seed potatoes)
Mid-Spring (1-2 weeks before last frost)
This is a good time for transplants of hardy vegetables and direct sowing of seeds that need a slightly warmer soil.
- Broccoli (transplants)
- Cabbage (transplants)
- Swiss Chard
- Onion sets
- Turnips
After Last Frost (The main planting window)
This is your busiest time. Wait until all danger of frost has passed, usually late May for most areas. Tender vegetables will not survive a chill.
- Tomatoes (transplants)
- Peppers (transplants)
- Eggplant (transplants)
- Cucumbers (seed or transplant)
- Beans (direct sow)
- Corn (direct sow)
- Squash & Zucchini (seed or transplant)
- Basil (seed or transplant)
Mid-Summer (For fall harvest)
Many gardeners forget about this crucial planting period. In July and August, you can sow seeds for vegetables that thrive in cooler fall weather.
- Lettuce (shade seeds from hot sun)
- Spinach
- Kale
- Radishes
- Carrots
- Beets
- Broccoli (transplants started indoors in June)
Understanding Your Pennsylvania Growing Zone
Your specific location makes a big difference. The state is divided by the Appalachian Mountains, creating distinct climates.
Zone 5b & 6a (Northern & Mountainous PA)
This includes areas like Scranton, State College, and the Laurel Highlands. You have a shorter growing season. Rely on cold-hardy crops, use season extenders like row covers, and focus on quick-maturing varieties of warm-season plants.
Zone 6b & 7a (Southern & Southeastern PA)
This includes Philadelphia, Lancaster, and Harrisburg. You enjoy a longer, warmer season. You can often plant warm-season crops a week or two earlier and have great success with longer-season crops like melons and sweet potatoes.
Step-by-Step: Planning Your Planting Calendar
- Find Your Frost Dates: Look up your area’s average last spring frost and first fall frost date. Your county extension office website is a reliable source.
- Work Backwards: For transplants like tomatoes, check the seed packet (“start seeds indoors 6-8 weeks before last frost”). Count backwards from your frost date to know when to start seeds inside.
- Check Soil Temp: Some seeds, like beans, need warm soil to germinate. A simple soil thermometer can prevent dissapointment.
- Keep Records: Note what you planted and when each year. This is your best tool for improving your schedule over time.
Tips for Extending Your Season
Don’t let frost dates limit you to much. Simple tools can add weeks to both ends of your growing season.
- Cold Frames: These are like mini-greenhouses for hardening off seedlings or protecting fall greens.
- Row Covers: Lightweight fabric laid over crops protects them from light frosts and pests.
- Mulch: A thick layer of straw or leaves insulates soil, keeping root vegetables warmer longer in fall.
- Container Gardening: Pots can be moved to sheltered areas during unexpected late or early frosts.
Common Planting Mistakes to Avoid
Even experienced gardeners can make these errors. Here’s what to watch for.
- Planting Too Early: Eagerness leads to frozen plants. Warm soil is more important than a warm air day.
- Ignoring Soil Health: Never skip adding compost. Good soil feeds your plants and improves drainage.
- Crowding Plants: Follow spacing on seed packets. Good air flow prevents disease.
- Forgetting Succession Planting: Sow quick crops like radishes or lettuce every 2 weeks for a continuous harvest, not just one big glut.
FAQ: Pennsylvania Vegetable Gardening
When is it safe to plant tomatoes in Pennsylvania?
Wait until after your last spring frost date. For most of PA, this is between May 10th and May 20th. Have covers ready just in case of a surprise cold night.
What can I plant in August in Pennsylvania?
August is perfect for planting fall crops. Direct sow lettuce, spinach, radishes, and carrots. You can also put in transplants of broccoli and cabbage for a late fall harvest.
How do I find my exact planting zone in PA?
Visit the USDA website and use their interactive zone map. Enter your zip code for the most precise zone information, which is more accurate than just knowing your city.
What are the best vegetables for beginners in PA?
Start with easy, reliable crops: lettuce, radishes, bush beans, zucchini, and tomatoes. They grow well here and give you quick results to boost your confidence.
Can I grow vegetables in Pennsylvania year-round?
With a sturdy cold frame or greenhouse, you can grow cold-hardy greens like spinach and mache through the winter. Otherwise, the main season runs from April through October.
Getting your timing right is the most important factor for a good garden yield. By following Pennsylvania’s optimal planting schedule and ajusting for your local conditions, you’ll give your vegetables the best possible start. Remember to keep notes each year, as your own garden is the best teacher. With a little planning, you’ll enjoy fresh food from your garden for many months.