Hand pollinating corn sounds like the sort of delicate work best left to professionals. I mean, what is even going on there? Tassels, ears, silks—these are not the familiar flower parts we all learned about in school.
But before you feel intimidated, consider this the next time you drive past a cornfield: there is a good chance that at least some of the crosses used to develop the corn growing there were made by a 15-year-old armed with a paper bag and a stapler.
That’s right. Much of the corn-breeding industry has long depended on teenagers looking to earn a little gas money over the summer.
Trust me: hand pollination is definitely something you can master.
In my previous work, we trained hundreds of teenagers to hand pollinate corn each summer. I have made hundreds of thousands of pollinations myself, and I can assure you that the physical process is quite simple. The greater challenge is learning to read the plant—to recognize when the tassel is shedding pollen, when the silks are receptive, and when the conditions are right for pollination.
Once you understand those basic cues, pollinating corn by hand takes only a few minutes.
In this guide, we’ll look at how corn is normally pollinated, why you might want to intervene, and the simple tools and techniques used by gardeners, seed savers, and corn breeders alike.
Hand pollination ensures that each corn plant receives ample pollen at just the right time, producing the largest, best-filled ears possible.
Why Hand Pollinate Corn?
Most corn does a perfectly good job of pollinating itself. Once the tassels begin shedding, the wind carries pollen throughout the planting, where some of it eventually lands on the silks of a neighboring plant.
Still, there are several reasons you might want to take matters into your own hands.
To Help Corn That Is Out of Sync
Perhaps your sweet corn has begun tasseling, and every time you brush past the plants, clouds of pale-yellow pollen drift through the air.
There is just one problem: there are no ears—or silks—in sight.
This sometimes happens when corn is exposed to drought, excessive heat, or other stressful growing conditions. The tassels continue to develop and begin shedding pollen, while development of the ears and silks falls behind. Some varieties are naturally more prone to this problem than others. It's a trait we select against in our own corn varieties, but even dependable corn can get a little out of sync when conditions are difficult.
Corn breeders use the word nick to describe the timing between pollen shed and silk emergence (think nick-of-time). When the tassels shed long before the silks emerge, the line is said to have "poor nick".
When you're a commercial breeder looking at hundreds of acres of corn with poor nick, it's a very bad day.
Fortunately, gardeners have more options when it comes to corn with poor nick. We'll discuss those options in the following sections.
To Save Pure Corn Seed
Corn is pollinated by wind, which means pollen does not necessarily stay where you planted it.
If another corn variety is flowering nearby, its pollen may reach your plants and fertilize some of the kernels. The ear you harvest may still look and taste perfectly normal, but the seed inside it will carry genetics from both varieties.
That is not a problem when you are growing corn only for eating. It becomes important when you want to save seed and grow the same variety again next year.
Hand pollination allows you to protect the silks before they are exposed, collect pollen from the variety you want to preserve, and apply that pollen yourself. Once the ear has been pollinated, it is covered again so that stray pollen cannot reach any remaining receptive silks.
For this, you will ideally need both tassel bags and shoot bags, along with a stapler or another way to secure and label the bags. Those supplies may look specialized, but the process itself is very straightforward, as we'll soon discuss.
To Make Your Own Corn Crosses
Perhaps you are not trying to prevent a cross at all. Perhaps you want to make one.
Hand pollination allows you to choose one plant to produce the ear and another to supply the pollen. You might cross a particularly sweet corn with one that has unusually beautiful kernels, or combine an early-maturing variety with one that has better flavor, stronger plants, or improved disease resistance.
The plant carrying the ear serves as the female parent, while the plant supplying the pollen serves as the male parent. The kernels that develop on the protected ear are the next generation of that cross.
This may sound like advanced plant breeding, but the physical act is nearly identical to saving pure seed. In both cases, you are doing two simple things:
- Keeping unwanted pollen away from the silks
- Applying pollen from the plants you have selected
Whether you are helping a stressed sweet-corn planting, preserving a favorite variety, or beginning a breeding project of your own, the process makes much more sense once you understand what the tassels, silks, and ears are actually doing.
Corn pollination begins with a tassel that is actively shedding pollen. This tassel is in "full shed," with anthers hanging down and opening to release thousands of pollen granules. With any luck, those pollen grains will make their way onto ear silks, kicking off the process of fertilization.
How Corn Pollination Works
Corn flowers do not look much like the flowers we learned to identify in school. There are no showy petals, and the male and female parts are located in completely different places on the plant.
Once you know what to look for, however, the system is remarkably easy to understand.
The Tassel Produces the Pollen
The tassel at the top of the corn plant is its male flowering structure. As the tassel matures, small flowers open and extend the pale-yellow or purplish anthers that produce pollen.
On a dry morning, you may be able to see pollen falling as you shake the plant or brush against the leaves. Sometimes the amount is substantial enough to resemble a little yellow cloud.
Corn relies primarily on the wind to move that pollen. Rather than aiming for a particular ear, the plant produces an enormous quantity and releases it into the surrounding air. Some of those pollen grains eventually land on the silks of nearby plants.
Although a corn plant can pollinate itself, pollen is often carried from one plant to another within the planting. This is one reason corn produces better-filled ears when it is grown in a block rather than in one long, narrow row.
The Ear Produces the Silks
The developing ear is the female flowering structure. It forms along the stalk, enclosed within layers of husk leaves.
The silks eventually grow out through the end of the husk, where they can intercept pollen from the air. What looks like a tangled mass is actually a remarkably organized collection of individual flower parts.
Every potential kernel on the ear has its own silk.
Each silk extends from a single ovule—the structure that can develop into a kernel—located along the cob. For every kernel to develop, pollen must successfully reach its corresponding silk.
Silks from the lower portion of the ear generally begin growing first, while those connected to the tip of the ear tend to emerge later. This helps explain why the tips of corn ears are often the first place you notice missing kernels when pollination conditions are less than ideal.
What Happens When Pollen Lands on a Silk?
A silk is more than a sticky surface for catching pollen. It provides the pathway that allows the pollen to reach the developing kernel deep inside the husk.
The process works like this:
- A pollen grain lands on a fresh, receptive silk.
- The pollen grain absorbs moisture and germinates.
- A pollen tube begins growing through the center of the silk.
- The pollen tube travels the entire length of the silk toward the ovule.
- Fertilization occurs, and the ovule begins developing into a kernel.
Since every kernel has its own silk, an ear of corn is not pollinated in a single event. Hundreds of separate pollen grains must each land on the correct silk and complete that journey.
Fortunately, the tassels normally produce far more pollen than the ears require.
When parts of an ear are empty, it indicates that the pollen did not reach the silk at the right time. The tips of these ears are empty because someone (me) did not cut the ear shoots back far enough before pollinating. The silks at the tip of the ear, which are the last to emerge, likely appeared the day after pollination but no pollen was present to fertilize them.
Why Are Some Kernels Missing?
When a silk fails to receive viable pollen, the ovule attached to it cannot develop into a normal kernel. This leaves an empty space on the mature ear.
Poor kernel set can occur when:
- The silks emerge after most of the pollen has already fallen.
- The planting is too small or arranged in a long, narrow row.
- Rain washes pollen away during the main shedding period.
- Hot, dry conditions interfere with silk growth or receptivity.
- Insects clip the silks before pollination is complete.
- Too little pollen reaches the later-emerging silks near the ear tip. (See picture above)
However, not every missing kernel represents a failure of pollination. Severe heat, drought, or nutrient stress can also cause newly fertilized kernels to stop developing.
Hand pollination cannot solve every source of poor ear fill, but it can make certain that plenty of fresh pollen reaches the silks at the right time. And once you understand which parts of the plant you are working with, the supplies required to do that are surprisingly simple.
What You Need to Hand Pollinate Corn
The tools you need depend on what you are trying to accomplish.
If your sweet corn is already shedding pollen and you simply want to improve kernel fill, you can act immediately with little more than a pair of scissors. If you are saving pure seed or making a controlled cross, a few specialized paper bags will make it possible to control exactly which pollen reaches the ear.
For Basic Hand Pollination
To improve seed set in a sweet corn planting, you will need:
- A pair of scissors
- A tassel that is actively shedding pollen
A tassel bag is helpful, but it is not absolutely necessary. You can bend a shedding tassel over the ear and gently shake it so that pollen falls directly onto the silks.
This is often the most practical option when you walk into the garden, discover that the tassels are already shedding, and realize the ears are only beginning to appear. You probably will not have time to order specialized pollination bags—and fortunately, you do not need them just to help an ear fill.
The scissors are important no matter which pollination method you use. Corn silks often emerge as a long, uneven ponytail. Clipping them back creates a short, uniform tuft, exposing more of the individual silks so they have an equal opportunity to receive pollen.
For Collecting and Applying Pollen
For a cleaner, more controlled hand pollination, it helps to have:
- Tassel bags
- Scissors
- A stapler
- A permanent marker
Tassel bags are tall, paper bags designed to fit over the tassel. They allow you to collect freshly shed pollen and then pour it directly over the prepared silks.
A stapler makes it easy to secure the bag around the tassel and later fasten it over the pollinated ear. A clipper stapler works best for this purpose, but a regular stapler will do.
For writing on the bags, I strongly recommend an industrial Sharpie or another fade-resistant industrial marker. Ordinary permanent-marker ink can fade surprisingly quickly after a few weeks in full sun, leaving you with a beautifully pollinated ear and no reliable record of what it is.
For Saving Pure Seed or Making a Controlled Cross
If your goal is genetic purity, you will also need:
- Shoot bags
Shoot bags are narrow paper bags placed over the developing ear before any silks emerge. Their purpose is to keep stray pollen from reaching the silks before you are ready to make the pollination.
Once the silks are exposed—even briefly—you can no longer be certain that the ear has not received pollen from another plant or variety. For that reason, shoot bags are essential when saving pure seed or making a deliberate cross.
The equipment may look specialized, but the complete toolkit is still remarkably simple: paper bags, scissors, a stapler, and a marker. And when the goal is merely to improve the fill on a sweet corn ear, even most of those are optional.
Shoot bags are used to prevent stray pollen from landing on the ears before hand-pollination can be performed. This is the only way to confidently produce pure seed for replanting or breeding.
When Is Corn Ready to Hand Pollinate?
Successful hand pollination depends far more on timing than technique. Before you begin, make sure the tassel is actively shedding, the silks are fresh, and the weather is suitable for working with corn pollen.
Is the Tassel Shedding Pollen?
A tassel that is ready to use will have anthers hanging from its branches. Depending on the variety, these may be pale yellow, reddish, or purple.
Give the tassel a gentle tap. If it releases a visible dusting of pollen, it is ready. A tassel may continue shedding for several days, although the amount of pollen can vary considerably from one morning to the next.
For a controlled pollination, we generally place a tassel bag over a tassel that has already begun shedding. The following morning, fresh pollen will collect inside the bag.
Are the Silks Ready?
Fresh silks are usually moist, flexible, and brightly colored. Depending on the variety, they may be pale green, yellow, pink, red, or nearly purple.
As silks age, they become brown and dry. An older silk may already have been pollinated, or it may no longer be as receptive to pollen. For the best results, work with fresh silks soon after they emerge.
When purity matters, the developing ear must be covered with a shoot bag before any silks become exposed. Once an uncovered silk emerges, you can no longer be certain that it has not already received stray pollen.
What Time of Day Should You Hand Pollinate Corn?
Corn is best pollinated during the morning, after the dew has dried but before the day becomes excessively hot.
Here on our farm, we typically begin making pollinations once the temperature reaches about 74°F. By then, the tassels are usually shedding well and any moisture on the tassel bags has had time to evaporate.
Wet pollen is dead pollen, so never begin until the tassels and the outsides of the bags are completely dry. If the morning is rainy or the plants remain covered with dew, pollination must wait.
As a practical rule, you can generally count on freshly collected corn pollen remaining viable for about four hours. It may last longer under cool conditions and considerably less time when temperatures are high.
Unless the weather is unusually cool, I like to have our corn pollinations completed by 1 p.m. As the day grows hotter, pollen loses viability more quickly, and the likelihood of a successful pollination begins to decline.
For a gardener making only a few pollinations, the rule is simple:
Wait until the tassel is dry and actively shedding, then pollinate during the coolest part of the morning available to you.
Once you have a shedding tassel, fresh silks, and dry weather, you are ready to begin.
Sometimes the tassels start shedding before the ears are silking, creating a synchronization issue during pollination. You can push these late-maturing ears ahead a few days by cutting them back to expose their silks. The darker green circle in the center of this ear shoot is its silk. When cutting back, aim for this circle to be about the size of a dime.
Corn Tassels but No Silks? Cut Back the Ear
If your corn is already shedding pollen but you cannot see any silks, the ear may simply be lagging a few days behind the tassel. In many cases, you can bring it forward by cutting back the tip of the ear shoot.
Start With the Top Ear
First, locate the uppermost ear shoot on the plant.
This may sound obvious, but corn plants sometimes produce second or even third ears farther down the stalk. Those lower ears may or may not develop fully. The top ear will produce the largest ear with the best kernel fill, so that is the one you should prepare and pollinate.
Feel for the Developing Ear
If the ear shoot is visible but no silks have emerged, begin at the tip and gently feeling your way down the husk, pinching with two fingers.
The end of the shoot will feel relatively soft and empty. Farther down, you should be able to feel where the developing ear begins inside the husk.
The goal is to shorten the husk and expose the growing silks without cutting into the ear itself.
Cut Back the Ear Shoot
Using a clean pair of scissors, cut approximately one inch from the tip of the ear shoot.
Look at the freshly cut surface. If you see a dark-green area in the center, you have reached the developing silks (see photo above). Ideally, you are looking for a silk cross-section roughly the size of a dime.
If you see only a very small spot of green—or no silk at all—continue cutting the shoot back in approximately half-inch intervals. Check the cut surface after each pass and proceed cautiously so you do not cut into the developing ear.
Once you expose a dime-sized section of silk, stop cutting and replace the shoot bag if using one. By the following morning, the silks will typically protrude about half an inch beyond the husk, forming a short, even tuft that is ready for pollination.
Next, we'll walk through a couple of methods for pollination. The method you use will depend on your goal. If you simply want better-filled sweet corn, you can transfer pollen directly from a tassel to the silks. If you are saving pure seed or making a deliberate cross, you will need to protect the ear and collect the pollen in a tassel bag.
If all you're after is better kernel set, cutting back the ears may be all that's needed. This ear was not silking 12 hours ago, so we cut it back to expose the silks (see previous picture). Given that the tassels are still shedding, it will go on to produce a nice, full ear.
The Quick Method for Better Ear Fill
This is the simplest option when your corn is already flowering and you just want to make sure the ears receive plenty of pollen.
1. Choose the Top Ear
Locate the uppermost ear on the plant. Although a corn plant may produce second or third ears farther down the stalk, the top ear will generally become the largest and best-filled.
Look for fresh silks emerging from the end of the husk. If the tassels are shedding but no silks are visible, use the cut-back method described above and return the following morning.
2. Clip the Silks
Corn silks often emerge as a long, uneven ponytail. If pollen is applied without clipping them, the longest silks can catch most of it while blocking the shorter silks underneath.
Use a clean pair of scissors to trim the silks into a short, even tuft just beyond the tip of the husk. This gives more of the silks an equal opportunity to receive pollen.
Do not worry about cutting the silks. Each one continues down through the husk to its corresponding potential kernel.
3. Find a Dry, Shedding Tassel
Choose a tassel with exposed anthers that releases visible pollen when tapped.
Wait until the tassel is completely dry. Pollen that has been wetted by rain or dew will no longer be viable.
Whenever possible, choose a tassel from a different plant within the same variety.
4. Shake the Tassel Over the Silks
Carefully bend the tassel over the ear and gently shake or tap it. You should see a fine cloud of pollen fall across the clipped tuft of silks.
Try to cover the entire surface rather than allowing all the pollen to fall on one side.
That is all a basic hand pollination requires.
5. Repeat the Next Morning, If Needed
One good application may be sufficient, but repeating the process the following morning can provide extra insurance—especially if pollen shed is light or the tassels and silks are only briefly overlapping.
Continue only while the silks remain fresh and viable pollen is available.
Performing a controlled pollination. Here, I am examining the pollen and shaking out the anthers, so that I can apply the pollen to the ear. The crease I've formed on the lower side of the bag creates a nice channel for directing the pollen exactly where I want it to go.
How to Make a Controlled Pollination
When saving pure seed or making a particular cross, the process begins before the silks are exposed. The goal is to prevent unknown pollen from reaching the ear and then replace it with pollen from the plants you have chosen.
1. Cover the Ear Before the Silks Emerge
Locate the top ear shoot and place a shoot bag over it before any silks are visible.
Once a silk has emerged into the open air, you can no longer be certain that it has not already received stray pollen. For that reason, check your plants frequently as flowering approaches. An ear can go from having no visible silks to a substantial ponytail very quickly.
If you cut the ear back to bring the silks forward, replace the shoot bag afterward. By the next morning, the new silk growth should form a short tuft beneath the bag.
2. Choose the Pollen Parent
If you are making a cross, this is your male parent. The plant carrying the ear is the female parent.
Write the identity of the pollen parent on a tassel bag with an industrial Sharpie before placing it over the tassel.
3. Bag the Tassel
Select a healthy plant with a tassel that has already begun shedding pollen. Place the tassel bag over the tassel during the afternoon before you plan to pollinate.
Gather the bottom of the bag around the stalk and secure it with a staple. I fold mine like a paper airplane, stapling the sides of the point together tightly enough that pollen will not fall out of the bottom of the bag.
If performing a cross, be sure to record the identity of the plant on the bag. This will be your male parent.
This process—cutting back ears and putting up pollen bags is called "setting up". Setting up is typically done the afternoon before pollination will be performed. Timing is less critical here. You can also set up in the evening if you prefer working in cooler temps.
5. The Next Morning—Collect the Pollen
The next morning, once the bags have dried and the temp is at least 74 degrees, locate the tassel bag.
Before removing the tassel bag, gently bend or shake the tassel so that loose pollen falls into the bottom of the bag.
Then release the staple and carefully lift the bag from the tassel (I typically shake the tassel as I remove it). Keep the bag upright so the pollen remains in the bottom rather than escaping into the wind.
You will see anthers mixed in with the pollen. If you'd like to remove them, form a crease on the front of the bag and gently tap until the anthers fall out (don't worry, they'll fall out before the pollen).
6. Prepare the Silks
Carry the pollen to the selected ear before removing its shoot bag.
Once everything is ready, uncover the ear and inspect the silks. If they've grown overnight, they're receptive. Silks that do not emerge are too old or have already been pollinated.
7. Apply the Pollen
Open the tassel bag and pour the pollen directly across the silks.
Move the bag slightly as you pour so that the pollen is distributed over the entire tuft. You do not need to rub the pollen into the silks or handle them individually.
Work efficiently, particularly on hot days. Corn pollen loses viability after it is shed, and that decline occurs more quickly as temperatures rise.
8. Cover and Secure the Ear
After applying the pollen, slide the tassel bag down over the ear. This larger bag replaces the shoot bag and protects the receptive silks from any additional pollen blowing through the field.
Gather the bottom of the bag around the stalk beneath the ear and staple it securely.
Take care not to staple through the ear, and make sure the bag is positioned so that rain cannot easily enter the opening.
9. Label the Pollination
Record the pollination directly on the bag using an industrial Sharpie.
For a deliberate cross, the female parent is written first:
Female parent × Male parent
Also include the date and any other information you will need to identify the ear at harvest.
When saving pure seed, the variety name and pollination date may be enough.
Label the bag immediately. Once you have made several pollinations, it becomes remarkably easy to forget which pollen went where.
10. Leave the Bag on the Ear
Leave the tassel bag in place as the ear develops. The silks will gradually brown and dry, while the ear enlarges beneath the bag.
The labeled bag can remain on the ear until harvest, keeping the identity of the pollination attached to the seed throughout the growing season.
And that is the whole process: protect the ear, collect dry pollen, clip the silks, pour on the pollen, and cover the ear again. The supplies may look unusual, but the pollination itself really is that simple.
This is where the magic happens. Here, I am applying the pollen directly to the silks. Those little bits of dust are the pollen grains, some of which will germinate inside the silks to kickstart fertilization.
Corn Pollination FAQs
Does corn need to be hand pollinated?
Usually, no. Corn is naturally pollinated by wind, and a healthy planting generally produces far more pollen than it needs.
Hand pollination is most useful when the tassels and silks are out of sync, when you are growing only a small number of plants, or when you need to control the parentage of the seed.
Is corn self-pollinating?
A corn plant can pollinate its own ears, but most ears receive pollen from several surrounding plants. Because corn pollen moves freely on the wind, different varieties flowering nearby can also cross with one another.
Do bees pollinate corn?
Bees sometimes visit corn tassels to collect pollen, but corn does not depend on them for pollination. The pollen is carried primarily by wind.
How often should I hand pollinate corn?
If you are simply trying to improve the fill on a sweet corn ear, one thorough pollination may be enough. You can repeat the process the following morning while the silks are still fresh if pollen shed is light or the planting is badly out of sync.
For seed saving or breeding, one controlled pollination with plenty of fresh, dry pollen is generally sufficient.
What is the best time of day to pollinate corn?
Pollinate in the morning, after the dew has dried but before the day becomes excessively hot.
Here on our farm, we usually begin once the temperature reaches about 74°F and the tassel bags are completely dry. Unless the weather is unusually cool, I like to finish by 1 p.m.
How long does corn pollen remain viable?
As a practical rule, you can usually count on dry corn pollen remaining viable for about four hours after it is shed. It may last longer in cool conditions and considerably less time when temperatures are high.
Use it as quickly as possible for the best results.
Can wet corn pollen still be used?
No. Wet pollen is dead pollen.
Do not collect or apply pollen while the tassels, tassel bags, or surrounding leaves are wet from rain or dew. Wait until everything is completely dry.
How can I tell whether a corn ear was pollinated?
After successful pollination, the silks gradually turn brown and dry while the ear begins to enlarge.
The surest confirmation comes later, when the kernels begin developing. Missing kernels usually indicate that the corresponding silks were not successfully pollinated, although severe heat, drought, or other stress can also cause young kernels to abort after fertilization.
Why is the tip of my corn ear missing kernels?
Silks connected to kernels near the tip of the ear usually emerge later than those lower on the cob. In an open-pollinated field, this is an indication that the pollen shed finished before all the silks were out. In hand pollination, poor tip fill indicates that you did not cut back far enough.
Poor tip fill can also result from heat, drought, insect damage, or other stress during pollination.
Should I clip the silks before hand pollinating?
Yes. Clipping long, uneven silks into a short, level tuft exposes more of them to the pollen.
Without clipping, the longest silks can lie across the top like a ponytail, intercepting the pollen before it reaches the silks beneath. A uniform tuft gives each silk a more equal chance of being pollinated.
Can you apply too much pollen to an ear?
Not really. Each silk connects to one potential kernel, and applying extra pollen will not make the ear produce more kernels than it already has ovules.
The important thing is to use fresh, dry pollen and distribute it across the entire tuft of silks.
What are the disadvantages of hand pollinating corn?
Hand pollination requires careful timing, and controlled pollinations require tassel bags, shoot bags, and accurate labeling. Each ear must also be handled individually.
For a home gardener pollinating only a few ears, however, the process takes very little time and requires almost no specialized equipment.
You'll feel like a pro when doing it, but hand pollination is a remarkably simple process. Once you can recognize a shedding tassel, a receptive ear, and the right conditions for pollination, you'll be well on your way to producing large, well-filled ears of corn.
Hand Pollinating Corn Is Easier Than It Looks
Hand pollinating corn may seem unfamiliar at first, but the process comes down to a few simple steps: find fresh silks, collect dry pollen, bring the two together, and protect the ear when purity matters.
And remember, you may not need to perform a full hand pollination at all. When the tassels and ears are slightly out of sync, cutting back the ear may be enough to bring the silks forward while pollen is still falling.
Either way, the most important skill is learning to read the plant. Once you can recognize a shedding tassel, a receptive tuft of silk, and the right weather for pollination, the rest takes only a few moments.
So, whether your faced with fears of a silk-less corn patch or you've got ambitions of creating your very own corn variety—take heart and know that this is one plant-breeding skill you can absolutely master in your own garden.
Excited to begin your corn growing or seed saving journey? Be sure to check out our extensive collection of heirloom corn seed. And if you have any pollination questions, drop them in the comments below. We're happy to help make your corn pollinations a success!
