Growing potatoes from seed potatoes involves planting small, sprouted tubers into loose, well-draining soil after the danger of frost passes. You must bury them four inches deep with sprouts facing upward.
Gardeners often make the mistake of planting whole large potatoes, which can rot before they sprout. Cutting large tubers into pieces with at least two eyes each ensures better success.
This guide covers selection, soil preparation, planting depth, hilling techniques, and the timing of the harvest.
What Are Seed Potatoes and Why Use Them?
Seed potatoes are tubers specifically grown and certified to be free of diseases and viruses. Using these instead of grocery store potatoes prevents the introduction of soil-borne pathogens into your garden beds.
Many store-bought potatoes undergo treatment with sprout inhibitors to extend shelf life. These chemicals prevent the eyes from developing, which makes them unsuitable for planting. Certified seed potatoes remain untreated, ensuring they have the energy reserves needed to produce healthy foliage and a productive root system.
| Potato Type | Maturity Time | Best Use |
|---|---|---|
| Early Season | 70 to 90 days | Fresh eating, salads |
| Mid-Season | 90 to 120 days | General purpose, storage |
| Late Season | 120 to 150 days | Long-term winter storage |
How to Prepare Seed Potatoes for Planting
Preparation begins by chitting, a process where tubers sit in a cool, bright area to encourage short, sturdy sprouts. This step jumpstarts growth and allows you to identify which tubers are most viable before they go into the ground.
If a seed potato is larger than a standard chicken egg, cut it into smaller sections. Each piece must contain at least two eyes, which are the small indentations where sprouts emerge. After cutting, let the pieces sit in a dry, shaded spot for two days. This allows the cut surface to form a protective callus, which prevents rot once the potato enters the moist soil.
What Soil Conditions Do Potatoes Require?
Potatoes thrive in loose, slightly acidic soil with a pH between 5.0 and 6.0 to prevent scab disease. The soil must drain well because standing water causes tubers to rot before they have a chance to mature.
Heavy clay soils often restrict tuber expansion and lead to misshapen potatoes. Gardeners often amend clay soil with organic matter like compost or aged leaves to improve drainage and aeration. If the soil is too dense, the roots struggle to pull in the oxygen needed for rapid growth.
How Deep Should You Plant Seed Potatoes?
Plant seed potatoes four inches deep in trenches or holes to protect them from temperature swings. Placing them at this depth also provides enough room to add soil later as the green stems grow taller.
If you plant too shallowly, the developing tubers may be exposed to sunlight. Exposure to light causes the skin to turn green and produces solanine, a compound that makes the potato taste bitter. Proper depth ensures that the tubers remain underground and protected from light throughout the entire growing season.
How to Manage Hilling for Higher Yields
Hilling involves mounding soil or mulch around the base of the potato plant as it grows to cover developing tubers. This practice keeps the potatoes buried, prevents greening, and creates a loose environment for the tubers to expand.
Start hilling when the plants reach about eight inches in height. Add three to four inches of soil or straw around the stems, leaving only the top leaves exposed. Repeat this process every two weeks until the plants begin to flower.
| Growth Stage | Action Required |
|---|---|
| Planting | Bury 4 inches deep |
| 8 inches tall | First hilling session |
| Flowering | Final hilling session |
| Yellowing leaves | Stop watering, prepare harvest |
How Much Water Do Potato Plants Need?
Potato plants require consistent moisture, typically one to two inches of water per week, to develop healthy tubers. Irregular watering often leads to knobby potatoes or internal hollow spots within the flesh.
Monitor the soil moisture by checking the top two inches of dirt. If the soil feels dry to the touch, provide a deep watering to reach the root zone. Avoid overhead watering if possible, as wet foliage can encourage the development of fungal diseases like late blight.
When Is the Best Time to Harvest Potatoes?
Harvesting occurs when the potato foliage turns yellow and begins to die back naturally. This indicates that the plant has finished moving energy into the tubers and they have reached their full size.
For new potatoes, you can harvest a few weeks after the plants finish flowering. These small, thin-skinned tubers are best eaten immediately. For storage potatoes, wait until the vines are completely brown and dry. This allows the potato skins to toughen, which is necessary for long-term storage in a cool, dark place.
How to Handle Common Potato Pests
The Colorado potato beetle is the most common threat, often appearing as striped adults or orange larvae on the leaves. Hand-picking these insects early in the season is the most effective way to prevent a large infestation.
Other pests include aphids and wireworms, which can damage the foliage or the tubers themselves. Maintaining a healthy garden with diverse plants often attracts beneficial insects that help keep these populations under control. If you notice holes in the leaves, inspect the underside of the foliage for eggs or larvae.
Frequently Asked Questions
Can you plant potatoes from the grocery store?
Grocery store potatoes are not recommended because they often carry diseases and receive sprout-inhibiting treatments. Certified seed potatoes are safer and provide a much higher chance of a successful harvest.
How far apart should you space potato plants?
Space potato plants 12 inches apart in rows that are at least 30 inches wide. This spacing allows enough room for hilling and ensures adequate airflow between the plants to prevent fungal issues.
Do potatoes need full sun to grow?
Potatoes require at least six to eight hours of direct sunlight every day to produce a good yield. Plants grown in partial shade often produce smaller tubers and are more susceptible to disease.
What is the purpose of chitting potatoes?
Chitting encourages the growth of short, thick sprouts before planting, which helps the plants establish themselves quickly. This process is especially useful in regions with shorter growing seasons where speed is vital.
Can you grow potatoes in containers?
Potatoes grow well in containers as long as the pot holds at least five gallons of soil and has drainage holes. Ensure the container is deep enough to allow for proper hilling as the plant develops.
How long do potatoes take to grow?
Potatoes typically take between 70 and 150 days to reach maturity, depending on the specific variety chosen. Early varieties mature faster, while late-season varieties require a longer period to reach their full size.
- Select certified disease-free seed potatoes.
- Cut large tubers to ensure at least two eyes per piece.
- Plant in loose, well-draining soil at a depth of four inches.
- Hill soil around stems to prevent greening and increase yield.
- Harvest only after the foliage has turned brown and died back.
