Growing Potatoes in Containers

Growing potatoes in containers is a fantastic option for those with limited garden space or urban gardeners looking to maximize their yields in small areas.

With the right techniques and care, you can enjoy a bountiful harvest of fresh, homegrown potatoes. Here are some key steps and tips to get you started.

Published: May 13, 2024.

Choosing the Right Container

Selecting an appropriate container is crucial for growing healthy potato plants. Here are some important considerations:

• Size and Depth: Potatoes need ample space to develop tubers. Choose a container that is at least 16 inches in diameter and 16 inches deep. Larger containers, such as half-barrels or large fabric grow bags, are ideal as they allow more room for tuber growth and can support more plants.
• Material: Containers can be made from various materials, including plastic, terracotta, wood, and fabric. Each material has its pros and cons:

• Plastic: Lightweight, affordable, and retains moisture well but can become too hot in direct sunlight.

• Terracotta: Breathable and attractive but can dry out quickly and is heavy.

• Wood: Natural and insulating but can rot over time if not treated properly.

• Fabric: Excellent drainage and air circulation, lightweight, and easy to store, but may require more frequent watering.

• Drainage: Proper drainage is essential to prevent waterlogging and root rot. Ensure the container has multiple drainage holes at the bottom. If necessary, drill additional holes to enhance drainage.
• Mobility: Consider the weight and mobility of the container. Containers can become quite heavy when filled with soil and plants. Using containers with wheels or placing them on a plant caddy can make it easier to move them around.

Selecting Potato Varieties

Different potato varieties offer varying tastes, textures, and growth characteristics. When selecting varieties for container gardening, consider the following factors:

Earliness

Potatoes are classified into early, mid-season, and late varieties based on their maturity time.

• Early Varieties: Mature in about 70-90 days. Ideal for container gardening because they require less time and space to produce a harvest. Examples include 'Yukon Gold' and 'Red Norland.'
• Mid-Season Varieties: Mature in about 90-110 days. Suitable for containers if you have more growing time and space. Examples include 'Kennebec' and 'Caribe.'
• Late Varieties: Mature in 110-135 days. Typically not recommended for containers due to their longer growth period and larger space requirements. Examples include 'Russet Burbank' and 'German Butterball.'

Growth Habit

Choose varieties with a compact growth habit, which are better suited for container gardening. Avoid varieties that produce long, sprawling vines.

Disease Resistance

Opt for varieties with good resistance to common potato diseases such as blight, scab, and nematodes. Disease-resistant varieties are easier to grow and maintain in containers.

Personal Preference

Consider the intended use of the potatoes. Some varieties are better for boiling, others for baking, mashing, or frying. Select varieties that match your culinary preferences.

Preparing the Soil

Potatoes thrive in well-draining, nutrient-rich soil. Preparing the right soil mix is crucial to support the growth and health of your potato plants. Here’s how to create the perfect soil environment:

Soil Composition

A loose, well-aerated soil mix is ideal for potatoes. Use a combination of:

• Potting Soil: Provides a lightweight base with good drainage.
• Compost: Adds essential nutrients and organic matter to the soil.
• Coconut Coir or Peat Moss: Improves moisture retention while maintaining good drainage.
• Perlite or Sand: Enhances drainage and prevents soil compaction.

pH Level

Potatoes prefer slightly acidic soil with a pH level between 5.0 and 6.0. Test your soil’s pH and adjust if necessary using garden lime to raise the pH or sulfur to lower it.

Fertilization

Mix a balanced, slow-release fertilizer into the soil before planting. A fertilizer with a higher phosphorus content (middle number) supports strong root and tuber development.

Avoid high-nitrogen fertilizers, which promote excessive foliage at the expense of tubers.

Soil Preparation

Combine the potting soil, compost, coconut coir or peat moss, and perlite or sand in a ratio of approximately 40% potting soil, 30% compost, 20% coconut coir or peat moss, and 10% perlite or sand. Mix thoroughly to ensure even distribution of nutrients and good drainage.

Planting Potatoes

Timing and technique are essential when planting potatoes in containers. Follow these guidelines to ensure your potatoes have the best start:

Seed Potatoes

Use certified seed potatoes to reduce the risk of disease. Cut larger seed potatoes into pieces, each with at least one or two “eyes” (sprouts). Allow the cut pieces to air dry for a day or two to form a protective callus over the cut surfaces.

Planting Time

Plant potatoes in early spring, once the danger of frost has passed and the soil temperature is consistently above 45°F (7°C).

Planting Depth

Fill the container with about 4-6 inches of prepared soil mix. Place the seed potato pieces, eyes up, on top of the soil, spacing them about 6 inches apart. Cover the seed potatoes with 4-6 inches of soil mix.

Hilling

As the potato plants grow, gradually add more soil mix to cover the stems, leaving the top few inches of foliage exposed. This process, known as hilling, encourages the development of more tubers along the buried stems. Continue hilling until the container is nearly full.

Watering and Fertilizing

Consistent watering and proper fertilization are key to a successful potato harvest. Discover the best practices for keeping your container-grown potatoes hydrated and well-fed:

Watering

Potatoes need consistent moisture, especially during tuber formation. Keep the soil evenly moist but not waterlogged.

Water deeply to encourage deep root growth, allowing the top inch of soil to dry out between waterings. Containers dry out more quickly than garden beds, so monitor moisture levels closely.

Mulching

Apply a layer of mulch, such as straw or shredded leaves, on top of the soil. Mulch helps retain moisture, regulate soil temperature, and reduce weed growth.

Fertilizing

Feed your potato plants with a balanced, water-soluble fertilizer every 2-4 weeks. A fertilizer with an N-P-K ratio of 5-10-10 or 10-20-20 works well. Avoid excessive nitrogen, which promotes foliage growth over tuber production.

Monitoring and Adjusting

Regularly check for signs of nutrient deficiencies, such as yellowing leaves (nitrogen deficiency) or purpling leaves (phosphorus deficiency). Adjust your fertilization schedule accordingly to address any issues.

Managing Pests and Diseases

Container gardening can help reduce the risk of pests and diseases, but vigilance is still necessary. Here’s how to identify and manage common potato pests and diseases:

Common Pests

• Aphids: Small, sap-sucking insects that can weaken plants. Control them by spraying with a strong jet of water or using insecticidal soap.
• Colorado Potato Beetles: Striped beetles that can defoliate plants. Handpick beetles and larvae, and use neem oil or biological controls like beneficial nematodes.
• Wireworms: Larvae of click beetles that bore into tubers. Use traps (like pieces of potato buried in the soil) to monitor and control wireworm populations.

Common Diseases

• Late Blight: A fungal disease that causes dark spots on leaves and tubers. Prevent by avoiding overhead watering, ensuring good air circulation, and removing affected plant parts. Use fungicides if necessary.
• Early Blight: Another fungal disease causing brown spots on leaves. Similar preventive measures as for late blight can be effective.
• Scab: A bacterial disease that causes rough, corky patches on tubers. Prevent by maintaining proper soil pH (slightly acidic) and using disease-resistant varieties.

Preventive Measures

• Crop Rotation: Avoid planting potatoes or other nightshades in the same soil for consecutive seasons to reduce disease buildup.
• Clean Containers: Disinfect containers between uses to eliminate any lingering pathogens.
• Healthy Seed Potatoes: Start with certified, disease-free seed potatoes to minimize the risk of introducing diseases.

Monitoring

Regularly inspect plants for signs of pests and diseases. Early detection and prompt action are key to effective management.

Harvesting and Storing Potatoes

Knowing when and how to harvest your potatoes is crucial for maximizing yield and storage life. Follow these tips for harvesting and storing your container-grown potatoes:

Harvest Timing

• New Potatoes: Harvest when plants begin to flower, typically 8-10 weeks after planting. These young, tender potatoes are great for immediate use.
• Mature Potatoes: Wait until the foliage turns yellow and dies back, usually 14-16 weeks after planting. This indicates the tubers have fully matured and are ready for storage.

Harvesting Technique

• For New Potatoes: Gently dig into the soil with your hands to avoid damaging the delicate tubers. Harvest a few at a time, leaving the rest to mature.
• For Mature Potatoes: Tip the container on its side and carefully empty out the soil. Gently sift through the soil to collect the tubers. Avoid bruising or cutting the potatoes, as damaged potatoes do not store well.

Curing

Allow harvested potatoes to cure in a cool, dark, and well-ventilated area for 1-2 weeks. This helps to toughen the skin and heal any minor cuts or bruises, extending storage life.

Storage

• Conditions: Store cured potatoes in a cool (40-50°F), dark, and humid place. A basement or root cellar is ideal. Avoid storing potatoes in the refrigerator, as this can cause the starches to convert to sugars, affecting flavor.
• Containers: Use breathable containers like burlap sacks, paper bags, or ventilated crates to store potatoes. This allows for air circulation and prevents moisture buildup.
• Regular Checks: Periodically inspect stored potatoes for signs of spoilage or sprouting. Remove any affected potatoes to prevent them from affecting the rest of the batch.

Growing potatoes in containers allows the gardener to harvest homegrown potatoes in positions where the soil is not suitable for growing potatoes or for gardeners to grow potatoes on terraces or balconies.

Either way, potatoes are relatively easy to grow and care for, just be sure that you have large enough pots and containers, with numerous drainage holes, and filled with good soil.