Potatoes require a cool but frost-free growing season. Grow potatoes through the summer in cool northern regions. Grow potatoes in fall, winter, and spring in hot summer southern regions.
- Plant potatoes as early as 4 to 6 weeks before the average last frost in spring or any time after the soil temperature warms to 40°F.
- Potatoes need 75 to 135 or more cool, frost-free days to reach harvest depending on the variety.
- Harvest late winter or spring-planted potatoes before daily temperatures average 80°
- Potatoes do not grow well in extreme heat or dry soil. High temperatures can cause mature potatoes to discolor inside.
Which potato to plant: Potato Types and Varieties.
Where to Plant Potatoes:
- Grow potatoes in full sun.
- Plant potatoes in fertile, well-drained soil rich in organic matter. Add several inches of aged-compost or commercial organic planting mix to planting beds before planting.
- Loosen the soil to 18 inches deep or grow potatoes in raised or mounded beds.
- Do not grow potatoes where the soil is compacted, heavy with clay, or constantly wet.
- A soil pH of 5.0 to 5.5 is best for potatoes. Alkaline soil increases the size of the crop but also increases the incidence of scab–a condition that affects the skin of the potato.
Planting Time for Early, Midseason, and Late Season Potatoes:
Potato varieties are classified according to the number of days they require to come to harvest. The ideal temperature for growing potatoes is 60° to 70°F; temperatures greater than 80°F are too warm for potatoes. Grow a variety that can come to harvest in cool to mild, not hot, weather.
- “Early” season (early maturing) varieties require 75 to 90 cool days to reach harvest. Early potatoes are the best choice for southern regions where summers become very warm or hot.
- “Midseason” varieties require 90 to 135 cool days to reach harvest.
- “Late-season” (also called long season) varieties require 135 to 160 cool days to reach harvest. Late-season potatoes are a good choice for northern regions where the weather stays mild all summer.
Plant potatoes no later than 12 weeks before the first expected autumn frost.
If you live where winters are mild and summers are hot, plant late season potatoes in winter for harvest in mid to late spring before the weather turns hot or plant early-season potatoes in late summer for a fall crop.
In mild summer regions, you can plant early, mid-season, and late-maturing cultivars in spring for an extended harvest season.
More tips: Potato Growing Tips.
Planting and Spacing Potatoes:
- Grow potatoes from “seed potatoes.” Seed potatoes can be whole potatoes or pieces of whole potatoes. A seed potato must have at least one eye to sprout. An “eye” is a puckered spot where sprouts develop.
- Plant certified disease-free seed potatoes. Supermarket potatoes have been chemically treated to prevent sprouting.
- Two or three weeks before planting, set seed potatoes in a bright, 65° to 70°F place to encourage sprouting.
- Cut whole seed potatoes into pieces with a sharp knife two days before planting; each piece should have at least two eyes
- Plant seed potatoes in a hole or trench 4 inches deep and cover with 2 inches of soil.
- Plant cut pieces with the cut side down.
- Sow seed potatoes 12 to 18 inches apart; space rows 24 to 36 inches apart.
- When seedlings (developing sprouts) emerge, add the remaining 2 inches of soil to the hole or trench.
- Keep adding light soil as plants grow tall. Leave the top two sets of leaves exposed.
- Potatoes also can be planted on top of the ground if they are covered with a 12-inch thick mulch of straw or hay.
- Each plant will produce about 5 to 10 potatoes or 3 to 4 pounds.
More tips: Potato Seed Starting Tips.
Container Growing Potatoes:
- Potatoes can be grown in containers. Use a shallow wooden box or a half barrel with the bottom removed; use stacked old tires or use special potato-growing bags or barrels.
- Plant seed potatoes at the bottom of the container.
- When plants grow from 8 to 10 inches tall, add enough soil to cover all but the top 2 or 3 sets of leaves. Continue this process until the maturity date for the variety you are growing then harvest.
Companion Plants for Potatoes:
- Grow potatoes with beans, cabbage, corn, eggplant.
- Avoid planting potatoes near cucumbers, pumpkins, squash, sunflowers, tomatoes, or raspberries. These plants are attacked by the same pests and diseases as potatoes.
Caring for Potatoes
- Keep potatoes evenly moist but not wet; water before the soil dries out.
- Potato tubers will rot if the soil is too wet.
- Even soil moisture is important; fluctuations in soil moisture—wet, dry, wet—can lead to cracked or knobby tubers.
- Mulch to protect tubers from the sun, conserve soil moisture, prevent the soil from becoming too warm, keep weeds down, and discourage pest insects.
- Feed potatoes by sprinkling 5-10-10 fertilizer across the planting bed before planting; add this again as a side dressing at midseason. Choose a fertilizer that includes calcium and magnesium.
- Avoid giving potatoes too much nitrogen; too much nitrogen will encourage foliage growth over tuber growth.
- Where the soil is poor, drench the soil with a cup or more of compost tea shortly after planting. Spray-mist foliage with compost tea every two weeks through the season.
- Be careful not to compact the soil around potatoes. Use boards between rows to avoid walking on the soil.
- Protect maturing tubers from sunlight by hilling up soil over plants or applying additional mulch to all but cover the plants. Exposed tubers will sunburn or their shoulders will become green (called greening). Green potatoes produce a chemical called solanine. Solanine is both bitter-tasting and toxic.
- Carefully cultivate around plants or mulch to keep weeds down.
Potato Pests and Diseases
- Potatoes can be attacked by Colorado potato beetles, leafhoppers, flea beetles, and aphids.
- Handpick both adults and larvae Colorado potato beetles and destroy them.
- Use Bacillus thuringiensis to control potato beetles, leafhoppers, and flea beetles.
- Knock aphids off plants with a strong blast of water.
- Potatoes are susceptible to blight and scab.
- Spray plants with compost tea every two weeks to control blights.
- Scab can cause potatoes to have rough skin but does not affect the eating quality of the potato.
- If scab is a problem maintain a soil pH below 5.2.
- Plant disease-resistant varieties and practice crop rotation.
More on potato problems: Potato Growing Problems: Troubleshooting.
Harvesting and Storing Potatoes
- Potato stems and leaves turn brown and flowers fade as tubers below ground mature.
- Potato tubers can be harvested at any size. Potatoes harvested before they mature are called new potatoes.
- As potatoes mature their skins harden. The skin of a new potato will easily peel off when rubbed. New potatoes cannot be stored but must be used right away.
- A potato plant will produce 3 to 6 regular-size potatoes and a number of small ones.
- Use a spading fork to dig up potatoes. Lift potatoes gently to avoid bruising or damaging the skins. Use your fingers to harvest potatoes if need be.
- Potatoes can be left in the ground past maturity until the first frost, but they are most nutritious if harvested when they mature.
- Protect harvested potatoes from sunlight; potatoes exposed to light will green and produce a bitter chemical compound called solanine.
- Allow potatoes to cure before storing them. Curing will harden the skins for storage. Set tubers in a single layer in a dark place at 50° to 60°F for two weeks to cure.
- Store potatoes at about 40°
- Save the best tubers for planting next season. Don’t save potatoes that are soft or discolored. Don’t save potatoes if any of the plants have been hit by a disease.
When to harvest: Potato Harvest Calendar.
Storing and Preserving Potatoes:
- Store potatoes in a dark, well-ventilated place at about 40°F.
- Potatoes will keep for about 6 months.
- Do not refrigerate potatoes.
- Prepared or new potatoes freeze well. Potatoes also can be dried.
More tips: How to Harvest and Store Potatoes.
Potato Varieties to Grow
- There are more than 100 varieties of potatoes.
- There are four basic potato categories: long whites, round whites, russets, and round reds. You can also grow potatoes with yellow or bluish-purple skins.
- Potato flesh may be white or match the skin color: red, yellow, or blue.
- Potatoes can be round, cylindrical, or finger-like, called fingerlings
- Potatoes can be categorized as moist or dry. Dry potatoes are good for baking and mashing (varieties include ‘Russet Burbank’ and ‘Butte’). Moist potatoes fall apart when cooked; they are a good choice for soups.
- Check your cooperative extension service for specific recommendations for your area.
Recommended Varieties: Here are potato varieties to grow in a home garden:
- ‘All Blue’: midseason; use mashed, steamed, roasted, and in salads.
- ‘Butte’: early season; baking.
- ‘Caribe’: early season; drought tolerant; all-purpose use.
- ‘Carola’: late-season; yellow flesh; all-purpose use.
- ‘Cranberry Red’: early- to midseason; use mashed, steamed, roasted, and in salads.
- ‘French Fingerling’: late-season; use roasted, baked, and in salads.
- ‘Katahdin’: midseason; use French-fried, baked, mashed, or roasted.
- ‘Purple Peruvian’: late-season; use roasted, baked, and in salads.
- ‘Red Gold’: midseason: all-purpose use.
- ‘Red Norland’: early season; use boiled, steamed, mashed, or in salads.
- ‘Red Thumb’: early season fingerling; roasting.
- ‘Rose Finn Apple’: late season; all-purpose use.
- ‘Russian Banana’: late-season; use roasted, baked, or in salads.
- ‘Yellow Finn’: midseason; all-purpose use.
- ‘Yukon Gold’: early season; use boiled, mashed, or in a salad.
- The potato is a perennial vegetable grown as an annual.
- Botanical name: Solanum tuberosum
- Origin: Chile, Peru, Mexico
More tips: Growing Organic Potatoes.