Alaska’s midnight sun allows potatoes to grow quickly when planted in late May or early June. Knowing the best time to plant potatoes in alaska is crucial for a successful harvest in this unique climate. This guide will walk you through everything you need to know, from soil temperature to variety selection.
Understanding Alaska’s Growing Season
Alaska’s growing season is short but intense. The long daylight hours, especially in the Interior and Southcentral regions, create ideal conditions for potatoes. However, frost can strike at any time, so timing is everything.
Potatoes need cool soil to start but warm weather to grow. They are sensitive to frost, both in spring and fall. The key is to plant after the last frost date and before the soil gets too warm.
Key Factors That Affect Planting Time
- Soil temperature: Potatoes need soil at least 45°F (7°C) at planting depth.
- Last frost date: Varies by region, from mid-May in coastal areas to early June in Interior.
- Daylight hours: Longer days mean faster growth, but also higher risk of sunscald.
- Potato variety: Early, mid-season, and late varieties have different maturity times.
Best Time To Plant Potatoes In Alaska
The ideal window for planting potatoes in Alaska is from late May to early June. This timing allows the soil to warm up enough while still giving the plants enough time to mature before the first fall frost. In Southcentral regions like Anchorage, aim for May 20 to June 5. In Fairbanks and the Interior, wait until June 1 to June 10.
If you plant too early, the seed pieces may rot in cold, wet soil. If you plant too late, the tubers won’t have enough time to develop before frost kills the vines. A good rule of thumb is to plant when the soil temperature at 4 inches deep reaches 45°F to 50°F.
Regional Planting Windows
- Southcentral Alaska (Anchorage, Mat-Su Valley): Late May to early June
- Interior Alaska (Fairbanks, Delta Junction): First week of June
- Southeast Alaska (Juneau, Ketchikan): Mid-May to late May
- Southwest Alaska (Bethel, Dillingham): Late May to early June
- Arctic/Remote (Barrow, Nome): Early June, if at all
Preparing Your Soil For Potatoes
Good soil preparation makes a big difference. Potatoes prefer loose, well-drained soil with a pH between 5.0 and 6.5. Heavy clay soils can cause misshapen tubers, while sandy soils may need more water.
Start by tilling the soil to a depth of 8-10 inches. Remove rocks and debris. Add compost or well-rotted manure to improve fertility. Avoid fresh manure, as it can burn the roots and introduce diseases.
Steps For Soil Preparation
- Test your soil pH with a home kit or send a sample to a lab.
- Amend with sulfur if pH is too high, or lime if too low.
- Mix in 2-3 inches of compost or aged manure.
- Add a balanced fertilizer like 10-10-10 at a rate of 1-2 pounds per 100 square feet.
- Rake the bed smooth and create furrows 4-6 inches deep.
Choosing The Right Potato Varieties
Not all potatoes are equal in Alaska. You need varieties that mature quickly and tolerate cool soils. Short-season varieties (70-90 days) are best. Look for “early” or “mid-season” types on the label.
Some top choices for Alaska include:
- Yukon Gold: Mid-season, buttery flavor, good for boiling and baking.
- Red Norland: Early, red skin, resists scab, great for new potatoes.
- Russet Burbank: Late, but widely adapted, good for baking and fries.
- Kennebec: Mid-season, white flesh, high yields, good storage.
- Carola: Early, yellow flesh, nutty flavor, disease-resistant.
Seed Potato Preparation
Buy certified seed potatoes from a local nursery or garden center. Avoid grocery store potatoes, as they may carry diseases. Cut seed potatoes into pieces about 1.5-2 inches in size, each with at least one “eye” (bud). Let the cut pieces dry for 24-48 hours before planting to prevent rot.
Planting Techniques For Alaska
There are several ways to plant potatoes in Alaska. The traditional method is in rows or hills. But raised beds, containers, and even grow bags work well in cold climates. The key is to keep the soil warm and well-drained.
Row Planting
- Dig furrows 4-6 inches deep, spaced 24-36 inches apart.
- Place seed pieces 8-12 inches apart in the furrow, eyes facing up.
- Cover with 2-3 inches of soil.
- As plants grow, hill soil up around the stems to protect tubers from light.
Raised Bed Planting
Raised beds warm up faster in spring and drain better. Fill beds with a mix of topsoil, compost, and sand. Plant seed pieces 4 inches deep and 8-10 inches apart. Water regularly, as raised beds dry out faster.
Container Growing
Use 5-gallon buckets or large grow bags. Fill with potting soil mixed with compost. Plant one seed piece per container at 4 inches deep. Place containers in a sunny spot and water daily. Harvest when the foliage dies back.
Caring For Your Potato Plants
Potatoes need consistent care throughout the growing season. Water is critical, especially during tuber formation. Too little water leads to small, misshapen tubers. Too much water can cause rot.
Watering
Give potatoes 1-2 inches of water per week, either from rain or irrigation. Water deeply to encourage deep roots. Avoid overhead watering late in the day, as wet foliage can promote blight. Drip irrigation or soaker hoses work best.
Fertilizing
Potatoes are heavy feeders. Apply a side dressing of fertilizer when plants are 6-8 inches tall. Use a low-nitrogen formula like 5-10-10 to encourage tuber growth over foliage. Repeat every 3-4 weeks until flowering.
Hilling
As plants grow, mound soil around the stems. This prevents tubers from turning green from sun exposure. Hill when plants are 6-8 inches tall, then again when they reach 12-15 inches. Use a hoe or your hands to pull soil up.
Pest And Disease Management
Common potato pests in Alaska include Colorado potato beetles, aphids, and wireworms. Diseases like late blight and scab can also be problems. Rotate crops every 2-3 years to reduce disease buildup. Use row covers to protect young plants from beetles.
- Check plants weekly for pests and remove them by hand.
- Apply neem oil or insecticidal soap for aphids.
- Use copper-based fungicides for blight prevention.
- Plant resistant varieties like Carola or Kennebec.
Harvesting Potatoes In Alaska
Harvest time depends on the variety and planting date. Early potatoes can be dug as soon as they reach usable size, usually 60-70 days after planting. For storage, wait until the vines die back and the skins are set.
In Alaska, harvest typically happens from late August to mid-September. Watch for the first fall frost, which will kill the vines. Once vines are dead, harvest within 2-3 weeks to avoid rot.
How To Harvest
- Use a garden fork or shovel to gently lift the plants.
- Start digging 12-18 inches from the plant to avoid cutting tubers.
- Shake off excess soil and place potatoes in a basket or crate.
- Let them dry in a cool, dark place for a few hours.
- Brush off remaining dirt, but do not wash until ready to use.
Storing Potatoes
Store potatoes in a cool, dark, well-ventilated area. Ideal temperature is 40-45°F (4-7°C). Do not refrigerate, as cold temperatures turn starch to sugar. Keep them in paper bags or cardboard boxes with holes. Check regularly for rot and remove any bad ones.
Common Mistakes To Avoid
Even experienced gardeners make mistakes. Here are some common ones to watch out for:
- Planting too early in cold, wet soil.
- Using grocery store potatoes that may carry diseases.
- Overwatering, which causes rot and fungal issues.
- Not hilling enough, leading to green tubers.
- Harvesting too late after frost damage.
Frequently Asked Questions
Can I Plant Potatoes In July In Alaska?
July is too late for most regions. Potatoes need at least 70 days to mature. Planting in July would risk frost damage before harvest. Stick to late May or early June.
Do I Need To Chit Potatoes Before Planting In Alaska?
Chitting (pre-sprouting) can give you a head start, but it’s not necessary. If you want to try, place seed pieces in a bright, cool spot for 2-3 weeks before planting. This can help early growth in cold soils.
What Is The Best Fertilizer For Potatoes In Alaska?
A balanced fertilizer like 10-10-10 works well at planting. Switch to a low-nitrogen formula like 5-10-10 after plants are 6 inches tall. Compost is also excellent for soil health.
How Deep Should I Plant Potatoes In Alaska?
Plant seed pieces 4-6 inches deep. This protects them from frost and keeps the soil temperature stable. Deeper planting can delay emergence, so stick to this depth.
Can I Grow Potatoes In Containers In Alaska?
Yes, containers work great, especially in colder areas. Use 5-gallon buckets or grow bags with drainage holes. Place them in full sun and water daily. Harvest when foliage dies back.
Final Tips For Success
Potato growing in Alaska is rewarding but requires attention to timing. Start with quality seed, prepare your soil well, and monitor weather forecasts. If a late frost threatens, cover plants with row covers or old blankets overnight.
Remember that the best time to plant potatoes in alaska is late May to early June, depending on your region. With proper care, you can enjoy a bountiful harvest of fresh, homegrown potatoes. The midnight sun works in your favor, so take advantage of it.
One more thing: keep a garden journal. Note planting dates, weather, and harvest results. This will help you refine your timing each year. Alaska’s growing conditions can vary, so learn from your own experience.
Happy gardening, and enjoy your potatoes!