Delaware’s coastal climate allows for an early April planting when the soil has drained from winter rains. Finding the best time to plant potatoes in delaware is key to a heavy harvest, and it really comes down to soil temperature and frost dates. You want the ground to be workable but not soggy, and the air to be warming up consistently.
Potatoes are a cool-season crop, so they can handle a light frost. But planting too early means the seed pieces might rot in cold, wet soil. Plant too late, and the hot summer weather will stop tuber growth. Let’s break down exactly when to get those spuds in the ground.
Best Time To Plant Potatoes In Delaware
The ideal window for planting potatoes in Delaware runs from late March through mid-April. For most of the state, aiming for the first two weeks of April is your safest bet. This timing lets the soil warm up enough while still giving the plants plenty of cool weather to grow.
In southern Delaware, near Sussex County, you can sometimes start a week earlier, around the last week of March. Northern areas, like New Castle County, often need to wait until mid-April. The key is to check your local soil temperature.
Checking Soil Temperature Before Planting
Potato seed pieces need soil that is at least 45°F (7°C) to start growing. Ideally, the soil should be between 50°F and 55°F. You can use a simple soil thermometer. Insert it 4 inches deep in your garden bed, and take the reading in the morning.
If the soil is too cold, the seed pieces will just sit there and may rot. If it’s too warm, the plants will grow fast but may produce fewer tubers. Wait until the soil has dried out enough that it doesn’t clump when you squeeze a handful.
Frost Dates For Delaware
Delaware’s last spring frost usually happens between April 10 and April 20. Potatoes can survive a light frost, but a hard freeze will kill the tops. If you plant in late March, be ready to cover the young shoots with row covers or straw if a freeze is forecast.
The first fall frost comes around mid-October. This gives you about 120 to 140 growing days, which is plenty for most potato varieties. Early-season potatoes can be harvested in 70 to 90 days, while main-season types need 100 to 130 days.
Preparing Your Soil For Potatoes
Good soil preparation makes a huge difference. Potatoes grow best in loose, well-drained soil with a pH between 5.0 and 6.0. If your soil is too alkaline, you can add sulfur to lower the pH. A soil test from your local extension office is cheap and helpful.
Work the soil to a depth of 8 to 10 inches. Remove rocks and large clumps. Add a 2-inch layer of compost or well-rotted manure. Avoid fresh manure, as it can cause scab on the potatoes. Mix in a balanced fertilizer like 10-10-10 at a rate of 1 pound per 100 square feet.
Choosing The Right Potato Variety
For Delaware, choose varieties that mature in 100 days or less. This helps you beat the summer heat. Here are some good options:
- Yukon Gold – medium-early, buttery flavor
- Red Norland – early, red skin, good for boiling
- Kennebec – main-season, great for baking and frying
- Carola – early, yellow flesh, very productive
- Adirondack Blue – mid-season, fun color, good yield
Buy certified seed potatoes from a garden center. Grocery store potatoes may carry diseases. Cut the seed potatoes into pieces about 1.5 inches across, with at least two eyes per piece. Let the cut pieces dry for 24 hours before planting to prevent rot.
Step-By-Step Planting Guide
Follow these steps for a successful potato planting in Delaware:
- Prepare the seed pieces: Cut and dry them a day before planting.
- Dig trenches: Make trenches 4 to 6 inches deep and 2 to 3 feet apart.
- Place the seed pieces: Space them 10 to 12 inches apart in the trench, with eyes facing up.
- Cover lightly: Cover the pieces with 2 to 3 inches of soil. Don’t fill the trench completely yet.
- Water well: Give the soil a good soaking after planting.
- Hilling: As the plants grow, pull soil up around the stems every 2 to 3 weeks. This prevents tubers from turning green.
Hilling is important. When the plants are about 6 inches tall, mound soil around the base. Repeat when they reach 12 inches. This gives the potatoes more room to grow and keeps them covered from sunlight.
Watering And Fertilizing
Potatoes need consistent moisture, especially when the tubers are forming. Give them about 1 to 2 inches of water per week. Use drip irrigation or a soaker hose to keep the leaves dry. Wet leaves can lead to blight.
Side-dress with a nitrogen fertilizer when the plants are 6 inches tall. Use about 1/4 cup of 10-10-10 per 10 feet of row. Don’t overdo nitrogen, or you’ll get lots of leaves and small tubers.
Common Problems In Delaware Potato Gardens
Delaware’s humid summers can cause some issues. Here are the most common problems and how to handle them:
- Late blight: Shows as dark spots on leaves. Use resistant varieties and avoid overhead watering.
- Colorado potato beetle: Yellow and black striped beetles. Hand-pick them or use neem oil.
- Scab: Rough, corky spots on the skin. Keep soil pH below 6.0 and use resistant varieties.
- Wireworms: Thin, wiry worms that tunnel into tubers. Rotate crops and plant after a cover crop.
Rotate your potato patch every year. Don’t plant potatoes in the same spot for at least three years. This reduces disease buildup in the soil.
Harvesting And Storing Potatoes
You can harvest new potatoes about 2 to 3 weeks after the plants flower. For full-sized potatoes, wait until the vines turn yellow and die back. This usually happens in late August to early September for early varieties, and into October for main-season types.
Harvest on a dry day. Gently dig the potatoes with a garden fork, being careful not to spear them. Let them sit on the ground for an hour or two to dry, but don’t leave them in direct sun for long.
Store potatoes in a cool, dark place with good air flow. Ideal temperature is 40°F to 50°F. Don’t store them in the refrigerator, as the cold turns the starch to sugar. A root cellar or a cool basement works well.
When To Plant Potatoes In Delaware For A Fall Crop
You can also plant a fall crop for a late harvest. The best time for a fall planting is from late July to early August. This gives the potatoes enough time to mature before the first frost. Use early-maturing varieties like Red Norland or Carola.
Fall potatoes need more water because of the heat. Mulch the soil with straw to keep it cool and moist. Harvest them after the first frost kills the tops, but before the ground freezes.
Frequently Asked Questions
Can I plant potatoes in Delaware in March?
Yes, but only in late March if the soil is dry and warm. Check the soil temperature first. If it’s below 45°F, wait until early April.
What is the latest I can plant potatoes in Delaware?
For a main crop, plant by mid-May. For a fall crop, plant by early August. Later plantings may not have enough time to mature.
Should I chit my seed potatoes before planting?
Chitting (letting them sprout indoors) can give you a head start. Place the seed potatoes in a cool, bright spot for 2 to 4 weeks before planting. This is optional but helpful for early planting.
How deep do I plant potatoes in Delaware?
Plant them 4 to 6 inches deep. Cover with 2 to 3 inches of soil initially, then hill them up as they grow. This keeps the tubers from getting sunburned.
Do potatoes need full sun in Delaware?
Yes, they need at least 6 to 8 hours of direct sunlight per day. Partial shade will reduce yields. Choose a sunny spot in your garden.
Final Tips For Delaware Potato Growers
Start with good seed potatoes and prepare your soil well. Plant at the right time, keep the soil moist, and hill the plants regularly. Watch for pests and diseases, and rotate your crops each year.
If you follow these guidelines, you’ll have a great potato harvest. The best time to plant potatoes in delaware is really about watching the weather and the soil. A little patience in the spring pays off with a big crop in the fall.
Remember to keep notes on what worked and what didn’t. Each season is a little different. With practice, you’ll find the perfect timing for your specific garden spot in Delaware.
Happy gardening, and enjoy those fresh, homegrown potatoes.