When Carrots Bloom

A cultivated carrot in bloom.
A cultivated carrot in bloom.

Bloomin’ carrots. Never seen ’em, right? Even if you’ve planted carrots in your garden for many years. That’s because carrots are biennials – plants that have a 2-year life cycle.

In the first season of life biennials grow in a vegetative state. All leaves, stems, roots, etc., but no flowers (no reproductive structure). Then, after going through the chilling period of winter they will bloom the next growing season, sending their progeny into the world.

But, as every biologist knows, every species has outliers. Individuals that fall outside what’s “normal” for the majority of individuals. It’s just part of nature… and statistics. Pick any definable characteristic for a living organism, measure it in a large sampling of the population, and you’ll end up with a classic bell curve of distribution. Ok, so for you statisticians out there that’s probably an over-simplification, but let’s just go with it for now.

Behold an outlier (picture above). From a single package of ordinary carrot seeds I bought this Spring there was one individual that would grow to produce flowers and seeds. Nothing to be alarmed about, just an interesting observation on the variability of life forms. Even within a species. As a biologist I see this as so unique that I just had to take a photo and write a short piece on it.

Now, you may think “Hey, I’ve seen this kind of flower before.” And you’re probably right. This flower is virtually identical to Queen Anne’s Lace (Daucus carota), also known as the wild carrot. When you look at wild carrots, with their paltry roots, it’s obvious that plant breeding has done a tremendous job of modifying this plant into the domesticated carrot.

When I was an undergrad at UW Madison I worked as a lab assistant in the ‘Carrot, Onion, Cucumber Lab’ in the horticulture department. Most of my job duties involved washing glassware. But, there was one job they had me do that I still remember a couple decades later: measuring the refractive index of the juice from carrot slices. The department was in the process of breeding varieties of carrots with more sweetness. One way to measure that sweetness was to crush a small sample of frozen carrot (freezing helped to break the cells within the tissue), squeeze the juice onto a refractometer, and measure the refractive index of the liquid. More sugar in the juice gave you a slightly higher refractive index.

Because the carrots could be re-grown from just their tops it was easy to take samples from the plants without destroying them completely. Those individuals that produced a root with more sugar were selected for in the next round of breeding. This is the classic way of modifying a species for desirable characteristics.

How does this apply to our unique outlier above? If your intent was to produce a variety of carrot that bloomed in the first season (essentially an annual) then you’d collect the seeds from this single plant and grow them out in a plot very far from any other carrots. As far as I can tell carrots rely on insects for pollination (not the wind), so planting them in an area that’s out of flying distance for most bees should suffice to isolate them. The flowers from this second generation could also be hand pollinated with a small feather or tiny paint brush, and then covered with mesh netting to keep insect pollinators out. I wasn’t part of that aspect of the Carrot Lab so I’m not sure what the preferable method is for carrots.

Then, from the individuals in that second generation you look for ones that are blooming in their first year. Collect their seeds, and repeat the process over again. This is called artificial selection – when a human steps in to encourage the growth and reproduction of individuals with certain characteristics. This process is very different from genetic modification of individuals. Directly playing with the genetic code might seem like a good thing at first glance. Here’s a good article on the pros and cons of genetically modifying food.

Modern Carrots

When you look at a wild plant like Queen Anne’s Lace it’s pretty obvious that domesticated carrots have come a long way from their wild cousins. Just out of curiosity I did a little research on varieties of carrots out there on the market. The common variety for commercial production is Imperator and Chanteney, while the most common for farmers’ markets is Nantes and Danvers. Commercial productions, whether on a large or small scale, involves producing a root that can grow in many soil types and tolerate some moderately rough handling on its way to market.

multi-colored-carrotsColored varieties in reds, yellows, and purples are becoming more popular. In my experience there doesn’t seem to be a great difference in taste between the traditional orange carrot and these newer colored varieties. Although it makes for a pretty side dish when you can serve purple and orange carrots together in the same dish! Nutritional differences are probably pretty minor, also. I’m guessing a carrot’s nutrition depends more on the quality of the soil and the weather than on what variety it is.

The World Carrot Museum in the UK (it’s a virtual museum, really) has a good write up about carrot nutrition and color.

Here’s wealth of information on carrots from UW Minnesota Extension. More than you’d probably want to know for your backyard garden or homestead. But, still some interesting reading!

———————Thought for the day:

Fat-free half-and-half — what’s the point?

2 thoughts on “When Carrots Bloom

    1. Not in my experience. It seems like once the plant blooms the energy is redirected to making seeds, so the root is smaller and very woody. It definitely smells like a carrot when you pull it, but the root is not edible. Yes, normally carrots are biennials, but once in a great while you’ll get one that blooms in its first year, like the one pictured above.

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