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How To Fertilize Sweet Corn In The Garden For Your Best Crop Ever!

If you grow sweet corn, you might be surprised at just how much of a difference a dose or two of fertilizer, given at the right time, can make to your crop’s overall performance. Not only can it lead to healthier plants, but larger and more densely packed ears as well.

There is simply nothing better than enjoying the incredible taste of fresh sweet corn in the summer. Especially when it’s fresh-picked from your own garden!

The fresh smell of a bright green husk. The crisp, tender, and oh-so juicy kernels. And of course, that sugary-sweet flavor that only comes from just-picked corn snatched from the stalks.

how to fertilize sweet corn
The colorful and tasty kernels of a fresh ear of sweet corn. For many, sweet corn is one of the most beloved summertime treats of all. In fact, there are hundreds of festivals and fairs completely devoted to the harvest of this delicious treat.

Growing your own sweet corn is certainly a little slice of heaven for sure. But there are definitely a few tricks when planting, growing and harvesting that can make a big difference in helping your crop reach it’s full potential.

One of the most important of all of those tips is fertilizing in the right way, and at the right time. Unlike many other vegetables, it’s not as simple as just throwing down an all purpose fertilizer.

How To Fertilize Sweet Corn

Sweet corn takes a fair amount of nutrients from the soil as it grows and matures. And without additional supplements throughout a season, it can easily run out of steam.

Especially if it happens to be growing in garden soil that had corn or other heavy feeding vegetables planted in it the previous year. But unlike many other vegetables, corn’s nutrient needs vary based on where it is in it’s growth cycle.

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Sweet corn benefits immensely from 3 simple and timely fertilizing applications. The first is at planting time. This dose, as you will see below, is different than the final two. It is an extremely light feeding that helps seeds to establish quickly without burning them out.

The second fertilizing comes as the corn reaches around 4 weeks of age. This dose, as with the final application (at 8 to 10 weeks) needs to be more powerful to allow the plant to produce big stalks and full ears.

Here is a look at each application, along with the best choices for providing the right nutrients at each step.

Step 1 – Fertilizing Seeds & Seedlings – How To Fertilize Sweet Corn

Corn seedlings require a lighter, more balanced dose of fertilizer. This helps the plant to develop good roots, stems and foliage. All of which are extremely important in setting the stage for ears to form within the husks.

At this early stage, too much power from too strong of a fertilizer will cause more harm than good. Not only can it stunt early growth, but it can even kill it off with too “hot” of a fertilizer.

compost seedlings
Compost is one of the best fertilizers of all for corn seedlings. The balanced nutrients help seeds get off to a great start, and keep moisture around the roots.

One of the best choices of all to use for seeds and seedlings is pure compost. Compost truly is the best all around naturally balanced fertilizer. Even better, it’s easy to make for free at home! (See : How To Create The Perfect Compost Pile)

Placing compost in the planting furrows gives corn a ready-to-go set of nutrients as they sprout. If your corn is already planted, you can also simply side dress or mulch young seedlings to provide them with a boost.

If you miss this stage, not all is lost. You can still help your sweet corn crop by applying the second and third fertilizers.

Steps 2 & 3 – How To Fertilize Sweet Corn

The second and third applications of fertilizer for sweet corn are by far the most important. It is at this stage when the roots of the crop are trying to absorb as much power as possible.

And when it comes to sweet corn, the most important nutrient is nitrogen. Nitrogen can quickly be depleted from the soil by a crop of corn. And resupplying it can be a critical part of the corn growing to full maturity.

fertilizing young corn
As corn reaches different stages in it’s growing cycle, it needs different nutrients. Here, as the corn nears four inches in height, it is time for a more powerful dose of nutrients.

Phosphorus is extremely important as well, as is potassium, but not at the same level as Nitrogen. Both aid in strong root and stalk development. Together, all three can really make a big difference in the overall performance and harvest.

There are a whole host of fertilizers on the market, but the key is to look for one that has an N-P-K ratio that has a higher nitrogen rating while still providing phosphorus and potassium as well.

That N-P-K ratio stands for nitrogen, phosphorus, and potassium in that order. And you will want to select one that has a higher N rating for a bigger dose of nitrogen. (Product Link : Organic Corn Fertilizer)

4 Weeks & 8 Weeks – When & How To Fertilize Sweet Corn

By four weeks, the corn crop has become established in the soil and can handle it’s first stronger supplement of nutrients.

How you apply the fertilizer is important. The best way to apply it by using a side dressing technique. Spread the fertilizer into the soil about 3 inches to each side of the main stalk down the row.

This allows the crop to absorb the nutrients down at the root level, and keeps the foliage from being damaged from the fertilizer. Fertilizer left on the foliage, or at the base can be too hot and burn the plant quite easily.

As for how much to apply, a good rule of thumb is about 1/8 of a cup for every two corn plants. Many times, rates of application are given in pounds per square foot, but for a home garden, that can be hard to relate. The cup ratio works well and is much easier to use in practical terms.

One More Dose – How To Fertilize Sweet Corn

Finally, at the 8 to 10 week mark of your crop, you will want to apply one more dose of the 16-16-8 fertilizer. Once again, apply at the same 1/8 cup rate for every two plants.

Now it is time to simply sit back and wait on that delicious sweet corn! Here is to fertilizing your sweet corn crop this year, and to enjoying some delicious ears later this summer.

This Is My Garden is a website dedicated to spreading the love and knowledge of gardening around the world. We publish two new garden articles each week. This article may contain affiliate links.