How Does it Grow?
How Does it Grow?
Telling the stories our food from field to fork

Botany has never been named the sexiest of subjects — but it may be now. The Sex Life of Vegetables is a light-hearted look at how some of our favorite vegetables reproduce. Instead of talking about anthers and stigmas — science class flashback! Are your eyes glazing over yet? — Nicole translates plant reproduction into terms we can all understand: people sex. The following is an excerpt from Nicole's upcoming book. Get a preview copy as a backer reward on Kickstarter.

 

CORN


Let’s go back to late summer. Fresh corn is cropping up in grocery bins and at farmers' markets, the bullet-shaped ears still swaddled snug in their green husks. You choose a long one with heft and girth, and do what we all do to check its freshness: you poke your fingertips into the muddy-yellow mop of corn silk, part the strands surrounding the tip of the ear and have a look to see if the kernels inside are plump and perfect. 

You cold, heartless pervert.

What you’re doing — right there in the open, my God — you’re fondling that poor corn’s private parts. No, not its willy — get your mind out of the gutter — but its girly bits. You’re having a good rummage in its bushier regions, and, to add insult to injury, you're assessing with the cold, clinical eye of a fertility analyst whether she’s produced good embryos.

Well, I hope you’re proud of yourself. We won’t even go into the indecent things you’ll do to that corn once you get it home — butter and salt and all sorts. 

For now, let’s rewind to the corn field. What do you see? Row upon row of brawny stalks standing cheek by jowl. Behold the city of corn, where each plant is a two-bedroom apartment in which a pubescent male and female reside. Sounds like a pretty sweet set-up for two eager teens, no? Well, there’s a hitch: this apartment is a duplex without a staircase — with the male confined to the top floor and the female stuck on the bottom floor. That is: the corn’s male parts, called the tassel, grow out the tippy-top of the corn stalk, while the female parts, the ear, grow below, with several inches of stalk in between — which might as well be a mile to a pair of hormonal youngsters.

To make matters worse, our damsel in distress downstairs is cursed with a chastity belt: a husk of thick, papery leaves that sheathes the kernels. The kernels, not yet plump, are her unfertilized eggs, all 750 or so of them. The husk does a first-class job at shielding the kernels from the male seed: the pollen that rains down from our prodigious male tassel upstairs.

The tassel is a cluster of thin, whip-like stems fringed with male flowers that don’t look like flowers at all but like pale green grains of rice delicately dangling. Each flower contains hundreds of thousands of grains of pollen — each as light as fairy dust. When our titillated tassel is ready to roar, he’ll shed his pollen twice a day, once in the morning and then again in the late afternoon. This can go on for a week or more. And whenever one tassel pollinates, the whole field of tassels are doing the same. 

What's more, because the pollen is so light, most of it doesn’t manage to fall directly from the tassel to the ear of the same plant — it’s caught by the wind, and deposited on ears next door, perhaps ten rows over, traveling up to half a mile. 

So you have thousands upon thousands of promiscuously pollinating tassels blowing in the breeze. That's one giant corn orgy.

But remember, there’s one big problem: Miss Chastity doesn’t make it easy for anyone, wrapped up as she is under that husk. But then remember this, too: never underestimate the ingenuity of a woman. To thwart the chastity belt, each kernel on a cob will send out a strand of silk through the top of the husk like Rapunzel letting down her hair. 

The strands are sticky, cloaked in microscopic hairs that catch the fine pollen dust. As soon as a pollen grain lands on a silk strand, it’s go time: the grain splits into two identical cells — a baby daddy and a wingman. The wingman literally paves the way to the egg: tunneling a pathway through the center of the six-to-eight-inch-long silk strand in a matter of hours. 

When the wingman reaches the ovary, he steps aside like a loyal buddy and let’s his twin slide down the tube to fertilize the egg. Together, all three make up a single swelling kernel of corn. (The wingman turns into the endosperm — the nutrient-rich fleshy part of the kernel that will feed the embryo within — the stuff that makes each kernel plump and juicy and appetizing to us corn-eaters).

The kernels don't actually send out their silks all at once — the ones at the base start, and like a wave, the rest of the kernels follow. That’s why you’re most likely to see sad shriveled kernels at the top of a cob when you pull back the husk to peek in at the grocery store. Typically what happened there is that the silks sent out from those top kernels were too late to the party; emerging only after the tassels had already exhausted their pollen supply.

Despite our own gastronomic satisfaction, the ultimate goal of all this hanky panky isn’t to fill grocery bins with plump ears of sweet corn. Reproduction is about continuing the species: fertilized embryos are supposed to get into the ground and grow into new apartment blocks for more sex-crazed teenagers. 

But that pesky good-for-nothing husk gets in the way again. If an ear of corn were to fall to the ground, it would take enormous luck for one of those kernels to germinate and take root, smothered as it is by those tightly wound leaves. It needs help. It needs a hand. Preferably one with opposable thumbs. One that can strip that husk off with a few authoritative tugs to unfetter the fertilized kernels. 

Better yet, a hand to build a machine that can shell 1,200 ears per minute, and then another machine — a great big, diesel-snorting super tractor — to plant those kernels in neat rows of freshly tilled earth.

Few plants are as dependent on humans as corn has evolved to be. And it seems casting their lot with us has been a smart move: today, corn is the world’s most important cereal crop. More corn covers the earth’s surface than most any other domesticated species — there’s more of them than even us: corn’s faithful midwife.