Planting Corn: Choosing the Right Variety and Soil Preparation

When it comes to planting corn, selecting the right variety is crucial. There are three primary types of corn: sweet corn, field corn, and popcorn. For the home gardener, sweet corn is typically the preferred choice. Consider the following factors when selecting your corn variety:

  • Maturity time
  • Disease resistance
  • Sweetness level
  • Colour

Once you’ve chosen your corn variety, it’s time to prepare the soil. Corn requires well-draining soil with a pH between 6.0 and 6.8. Amend the soil with compost or well-rotted manure to improve fertility and soil structure. Additionally, conduct a soil test to determine the specific nutrient needs of your plot.

Days to Grow60-100 days, depending on the variety
Square Foot Garden Spacing1 plant per square foot
Gardening EffortModerate
When to Plant2-3 weeks after last frost date
Yield1-2 ears per plant
Frost TolerancePoor
Hours of Light Needed10-12 hours of sunlight daily
Soil ConditionsWell-draining, pH 6.0-6.8
Days to Maturity60-100 days, depending on the variety

Gardening Shortcut Links

Square Foot Gardening Section

Starting corn indoors and transplanting 

Starting corn indoors and transplanting after the risk of frost has passed can give your corn crop a head start, especially in areas with shorter growing seasons like ours. While corn is generally best sown directly outdoors, transplanting can be successful with proper care and attention. The trick is to use deep pots and be very careful of the roots.

To start corn indoors, begin by selecting containers at least 3-4 inches deep with drainage holes. Biodegradable pots, such as peat pots or cowpots, are ideal for corn since they can be planted directly into the ground, reducing the risk of transplant shock. Next, fill the pots with a high-quality seed-starting mix, providing a well-draining and nutrient-rich environment for the seedlings.

Sow the corn seeds 1-1.5 inches deep and cover them with the seed-starting mix. Water the seeds thoroughly and maintain consistent moisture during the germination process. Place the pots in a warm area with a temperature between 70-75°F (21-24°C) to encourage germination, which should occur within 7-10 days.

Once the seeds have germinated, move the pots to a sunny location, ideally near a south-facing window, or use grow lights to provide 12-14 hours of light per day. Rotate the pots regularly to ensure even growth and prevent seedlings from becoming leggy.

Begin the hardening-off process 1-2 weeks before transplanting by gradually exposing the corn seedlings to outdoor conditions. Start by placing the seedlings outdoors in a protected area for a few hours each day, gradually increasing the time spent outside and the exposure to sunlight and wind over a week.

When the risk of frost has passed, and the soil temperature has reached 60°F (15°C), transplant the corn seedlings into the prepared garden bed. If using biodegradable pots, plant the entire pot, ensuring that the pot’s rim is below the soil surface to prevent wicking of moisture away from the roots. Space the seedlings 12-18 inches apart in rows 30-36 inches apart. Water the transplants thoroughly after planting and continue to provide consistent moisture throughout the growing season.

Planting Corn: Sowing and Spacing

The optimal time to plant corn is when soil temperatures reach 60°F (15°C). This is typically 2-3 weeks after the last frost date. When sowing seeds, follow these guidelines:

  • Plant seeds 1-1.5 inches deep
  • Space seeds 4-6 inches apart
  • Space rows 30-36 inches apart

To ensure good pollination, plant corn in blocks rather than single rows. This will improve the chances of successful pollination and a bountiful harvest.

Growing Corn: Fertilization, Watering, and Weed Control

Corn is a heavy feeder, requiring ample nitrogen, phosphorus, and potassium. Apply a balanced, slow-release fertilizer at planting time and again when the plants are 12 inches tall. Additionally, consider a side-dressing of nitrogen when the plants reach 18-24 inches in height.

Watering is essential for successful corn growth, as the plants require consistent moisture. Provide 1-1.5 inches of water per week through rainfall or supplemental irrigation. Drip irrigation is a highly effective method for maintaining consistent soil moisture.

Weed control is crucial for healthy corn plants, as weeds compete for nutrients and water. Cultivate the soil around your corn plants regularly to keep weeds at bay, taking care not to damage the shallow root system of the corn plants.

Corn Pests and Diseases: Prevention and Management

Corn plants are susceptible to various pests and diseases. Some common pests include:

  • Corn earworms
  • European corn borers
  • Cutworms
  • Aphids

To prevent and manage these pests, use a combination of cultural, biological, and chemical controls. This includes practices such as crop rotation, releasing beneficial insects, and applying insecticides when necessary.

Common corn diseases include:

  • Corn smut
  • Rust
  • Leaf blights
  • Stalk rots
Corn Smut

Corn Smut

To prevent and manage diseases, select disease-resistant varieties, practice crop rotation, and maintain proper plant spacing for adequate air circulation.

Harvesting Corn: When and How

Timing is critical when harvesting corn. For sweet corn, the optimal harvest time is when the kernels are full, and plump and the juice inside is milky. This is typically 18-24 days after the appearance of silks. To harvest, grasp the ear firmly and twist it downward, snapping it from the stalk.

Storing Corn: Preserving Freshness and Quality

To maximize the quality and freshness of your harvested corn, follow these storage tips:

  1. Store corn in the husk to maintain moisture
  2. Refrigerate corn as soon as possible after harvesting
  3. Use airtight containers or plastic bags to minimize moisture loss

Consume or process corn within 2-3 days for optimal flavour and quality.

For longer-term storage, you can preserve your corn harvest by freezing, canning, or drying. Each method has its advantages and specific processes to follow:

Freezing Corn: A Simple and Efficient Method

Freezing is a convenient way to store corn while preserving its flavour and nutrients. Follow these steps to freeze corn:

  1. Remove the husk and silk from the corn.
  2. Blanch the corn by boiling it for 4-6 minutes, then cool it in ice water to stop the cooking process.
  3. Cut the kernels from the cob using a sharp knife, being careful not to cut into the cob.
  4. Spread the kernels in a single layer on a baking sheet and freeze until solid.
  5. Transfer the frozen kernels to airtight containers or freezer bags, removing as much air as possible.
  6. Label the containers with the date and store them in the freezer for up to 12 months.

Canning Corn: A Traditional Preservation Technique

Canning is another effective method for storing corn. It requires a pressure canner to ensure the corn is safely preserved. Follow these steps for canning corn:

  1. Remove the husk and silk from the corn.
  2. Cut the kernels from the cob, being careful not to cut into the cob.
  3. Fill sterilized canning jars with corn kernels, leaving 1 inch of headspace at the top.
  4. Add boiling water or light syrup to the jars, maintaining the 1-inch headspace.
  5. Wipe the jar rims clean and secure the lids with canning rings.
  6. Process the jars in a pressure canner according to the manufacturer’s instructions and the recommended processing times for your altitude.
  7. Once processed, allow the jars to cool, then check the seals and store them in a cool, dark place for up to 12-18 months.

Drying Corn: A Long-lasting Storage Option

Drying corn is an age-old method of preservation that results in a versatile, shelf-stable product. Here’s how to dry corn:

  1. Remove the husk and silk from the corn.
  2. Blanch the corn by boiling it for 4-6 minutes, then cool it quickly in ice water to stop the cooking process.
  3. Cut the kernels from the cob using a sharp knife, being careful not to cut into the cob.
  4. Spread the kernels in a single layer on a screen or drying rack.
  5. Place the screen or rack in a well-ventilated area or use a food dehydrator set at 130-140°F (54-60°C) to dry the corn.
  6. Dry the corn until it is hard and brittle, which may take several days or up to 24 hours in a dehydrator.
  7. Store the dried corn in airtight containers in a cool, dark place for up to 12 months.

In conclusion, planting, growing, harvesting, and storing corn can be a rewarding and enjoyable process for gardeners of all experience levels. By following the guidelines and techniques outlined in this comprehensive guide, you can successfully grow and preserve a bountiful corn harvest to enjoy throughout the year.

Seeds and planting
Links and Resources

Recommended Products
(These are some of what I use)

These nursery bags
These Grow bags

Pages Seeds Page
Get a Head Start on Spring: The Benefits of Starting Your Seeds Indoors
Saving Vegetable Seeds: A Comprehensive Guide to Gardening Success Planting Guide
Pollock Tomatoes (North hardy Tomato variety)
Tomatoes (Useful information on starting tomatoes from seed)

DIY Garden Irrigation System: A Detailed Guide for Northwest Ontario

Blog Posts

When to start planting seeds
Germination testing your seeds
Looking for sources for seeds?
Heirloom seeds
Chitting your way to more potatoes
So it's before the first frost; what can I plant?


Individual seed and plant information is available in the  "Gardening Shortcut Links" above under "North Hardy Plants to grow". I have successfully grown all of these, and most I grow year to year.






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