How to Plant Corn: A Complete Organic Growing Guide

Let’s talk about a crop many people leave out of their gardens. Corn is not only possible but incredibly rewarding to grow in a home garden!

Locally grown corn is probably one of the best, tastiest things you can get your hands on. If you are anticipating sweet corn as much as I am, you’ll want to learn my secret for growing amazing corn!

In this growing guide, I’ll teach you how to plant corn, when to plant, how to manage common pests, and how to select the best corn seed for you. Let’s start growing!

Growing Corn

As promised when we bought a farm, I planted a patch of corn there. I decided to go BIG and plant the biggest patch of sweet corn I have ever planted- two acres!

Corn is one of our favorite summer vegetables. It is delicious, raw or cooked. I am looking forward to harvesting corn and enjoying it!

Selecting the Perfect Corn Varieties

Believe it or not, corn is actually grass! There are four different types of corn: sweet corn, flint corn, dent corn, and popcorn. These differ in their water and starch content, which also determines how they are used.

To further break it down, there are different varieties within each of the four types. I recommend learning about the various types of corn before you buy corn seeds so that you don’t end up growing something you don’t want!

Sweet corn is the most popular choice for growing in home gardens. People love it for its sweetness and soft kernels. It's great for eating fresh and comes in many varieties, such as Silver Queen Corn, Peaches and Cream Sweet Corn, Golden Bantam 12 Corn, and Bodacious Sweet Corn.

If you haven't ever tasted homegrown popcorn, you are missing out! Varieties like Red Strawberry Popcorn and Miniature Blue Popcorn are delicious, low-calorie snacks that you can grow right at home.

Flint corn (like this Glass Gem Corn) is ideal for grinding and making cornmeal, grits, and corn flour. Dent corn (like this Oaxacan Green Dent Corn), with its low moisture and high carbohydrate content, is commonly used for animal feed but is also great for milling into cornmeal and flour.

When to Plant Corn for a Successful Harvest

You may have heard the saying “knee high by the 4th of July”. Most people take that saying to mean that corn must be planted in time to reach knee height by the 4th of July, or it is behind schedule.

Most people don’t realize that this saying refers to the first planting of corn. Like most crops, succession planting can be used for corn! Corn farmers are still planting corn well into July, even where I live in Michigan, to allow for a continual harvest throughout the fall.

That said, the important factors in timing when to plant corn are soil temperature and allowing enough growing days for that corn variety to mature. To calculate whether you have enough growing days to plant corn, you must know the length of your growing season and the number of days to maturity for that variety.

• Length of Growing Season - The average number of days between the last spring frost and the first fall frost in your area is the length of your growing season. Mature corn may survive a light frost, but it will not survive a hard freeze. Pro-Tip: Use this free online frost dates calculator for the U.S. and Canada to learn your last and first frost dates and growing season length.

• Days to Maturity - Look at the seed packet to learn how many days it will take for each corn to mature. You can find varieties of sweet corn that mature in just 75 days and varieties of dent corn that take 120 days to mature. Choose varieties that will have enough time to mature in the length of your growing season.

• Soil Temperature - I recommend planting corn when soil temperatures are 60°F and above. Planting corn when the weather is too cold will lead to poor germination rates.

If you want to watch your corn pop up in rows, use the information above to determine when to plant corn in your garden. 

I prefer to grow sweet corn because it takes much less time. I can plant a sweet corn, like Ambrosia, in July when the soil temperature is nice and warm, and then harvest it 75 to 85 days later at the end of September.

What You Need to Know About Corn Pollination

You need to know that you can’t just grow a couple of corn seeds in a pot or even one straight row of corn. You just won’t get good results because you won’t have good pollination! If you have ever seen an ear of corn that is sparse with patchy kernels here and there (like in the image above), that was caused by a pollination issue.

Corn is wind pollinated. When the wind blows, it moves the tassels, knocking pollen off and spreading it throughout the air so it can land on the silks of the corn. Each silk goes back to a kernel and needs to be pollinated by a piece of pollen falling from the tassels.

This is why corn should be planted in a block. To ensure good pollination, the minimum plot size you should plant corn in is a 4-foot by 4-foot block.

Quick Guide on How to Plant Corn

When you’re ready to plant corn, gather your supplies, such as corn seeds and fertilizer, and don’t forget my secret ingredient for growing great corn—alfalfa pellets!

Alfalfa pellets are an inexpensive product high in nitrogen and organic matter. They help loosen the soil and slowly release nitrogen as they break down. You can usually find alfalfa pellets in the animal feed section of your local farm supply store.

Follow these steps to plant corn:

1.  Location  - Choose a location to plant corn that provides full sun. Allow for 7 to 10 hours of full direct sunlight. 

2.  Soil pH - The optimal pH for corn is 6.0 to 7.0, but corn is not too finicky. 

3.  Amend Soil - Amend the soil with finished compost. Corn requires loose, fluffy soil. Compacted soil is not good for growing corn. Pro-Tip: Don’t flip or aggressively work the soil. I use double digging to incorporate compost into soil. Spread the compost evenly across the soil, push your shovel or broad fork into the soil about 4” deep, wiggle it around to loosen the soil and then pull it out. 

4.  Broadcast Fertilizer  - Broadcast the fertilizer and alfalfa pellets over the top of the soil and evenly incorporate them in by lightly fluffing the top 1-inch of the seed bed. I recommend fertilizing corn with a naturally derived fertilizer, like Trifecta+, with good amounts of nitrogen, phosphorus, and potassium. Follow the application directions on the fertilizer and use about 1 pound of alfalfa pellets for every 8 to 12 square feet.

5.  Planting Depth & Spacing - Prepare shallow rows 1 ½ to 2 inches deep and 8 to 10 inches apart. (Remember, you need to plant at least a 4-foot by 4-foot block for proper pollination.)

6. Sow Seeds - Direct sow seeds 6 inches apart in the prepared rows and gently cover them with soil. For guaranteed success, I place two seeds together in each planting location and thin them out as needed after they sprout.

7.  Water - Thoroughly water at the time of planting. After that, water the corn once a week as needed. Pro-Tip: Corn is a drought-tolerant crop, but that leads people to make the common mistake of underwatering. If you want nice, plump, juicy kernels that are not starchy and chewy, you need to make sure that each corn plant gets adequate water. 

Managing Common Corn Pests & Diseases Organically

Keeping corn healthy is key to a good harvest. When growing corn, watch for these common pests and diseases.

Garden to Table: Harvesting & Preserving Corn

Now that you know how to plant corn, read this blog post to learn when to harvest corn. Sweet corn is usually ready to harvest when the silks turn brown and dry.

Preserving corn and other vegetables will allow you to save money and provide nutrient-dense vegetables for your family all year round. This video shows how to freeze corn so that you can preserve garden-fresh corn for the winter months.

I hope you enjoyed this complete growing guide and learned something new today!