Are Hydroponic Vegetables Less Nutritious?
When it comes to hydroponics versus conventionally grown produce, there are lots of pros and cons to consider. Nutrition Diva weighs them all.
Monica Reinagel, MS, LD/N, CNS
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Are Hydroponic Vegetables Less Nutritious?
Gina writes: “We have a new hydroponic veggie grower in town. How do they compare nutritionally to soil-grown veggies?”
How Are Hydroponic Vegetables Grown?
Hydroponics is a sort of high-tech farming. Instead of waiting until the right time of year, planting seeds in dirt, adding fertilizer, hoping for enough rain (but not too much), and combatting whatever pests, diseases, and or poachers might invade your field, hydroponic plants are nurtured indoors under grow lights, in a sterile medium that holds water and nutrients close to the plant roots, with precisely controlled temperature and humidity.
What Are the Pros and Cons of Hydroponic Farming?
Because the plants are not subject to the unpredictable depredations of nature, there is a lot less crop loss. Farmers don’t have to worry about drought and hailstorms. They need fewer pesticides, herbicides, fungicides, and so on.
See also: How to Reduce Your Exposure to Pesticides
Because they can artificially control the length of the day and the air temperature, hydroponic farmers are also effectively freed from the constraints of traditional growing seasons. They can grow tomatoes in January and spinach in July if they want to. Then again, hydroponic farmers also have to pay a utility bill instead of instead of getting most of their sunlight and water for free.
Hydroponic vegetables can also be grown just about anywhere. That means that Alaskans can enjoy fresh, local lettuce instead of paying for it to be flown in from the lower 48. Many argue that hydroponic cultivation is a more sustainable form of agriculture, consuming less water, space, and energy.
The fact that hydroponic vegetables never come into contact with soil also means that we don’t need to worry about them absorbing heavy metals from the soil, or being contaminated by disease-causing bacteria that may exist in manure-based fertilizers. On the other hand, we’d also miss out on the potential benefits of beneficial soil-based organisms.
See also: Are Soil-Based Organisms Beneficial?
Are Hydroponic Vegetables Less Flavorful?
Many argue that despite the obvious advantages, taking the plant out of nature takes some of the natural flavor out of the plant. And at an intuitive level, this makes sense. How could something grown under a fluorescent light bulb in a soil-less medium have the same flavor as a plant that has soaked up natural sunshine and wiggled its rooty little toes in the earth?
I have had lots of hydroponic lettuce that was just as flavorful as lettuce I’ve grown in my own garden. Then again, one of the pleasures of home grown carrots fresh from the garden is that, even after they’ve been scrubbed, they retain the earthy taste of the soil—and that would be hard to replicate hydroponically.
For some vegetables, the specific variety may have more of an impact on the flavor than whether it was grown in soil or a hydroponic medium. For all the romance of vine-ripened tomatoes, new varieties of hydroponic tomatoes have started to beat them out in blind taste tests. After all, when you don’t have to breed varieties to be able to withstand drought or blight, you can breed them to be more flavorful. Manipulating the nutrient mix they’re grown in, in particular the minerals, can also improve the flavor of hydroponic veggies.
But What About the Nutritional Value?
It’s also impossible to generalize about whether hydroponically grown veggies are more or less nutritious than conventionally grown. Part of this, again, will depend on the varieties being grown. And part of it depends on the growing medium. By increasing the concentration of nutrients in the hydroponic medium, you can actually increase the nutrient content of the vegetable.
Whether conventional or hydroponic, many of those nutrients will begin to fade once the produce has been harvested. I’ve said this before about organic produce and it is equally applicable to hydroponics: How fresh the produce is may have more of an impact on its nutrient quality than how it was grown. Lettuce or tomatoes from a local hydroponic grower may be more nutritious than conventional or organic produce that’s spent a week in transit, simply because less time has elapsed.
Either way, however, there is still plenty of nutrition left in those veggies. The best way to maximize the nutritional value you get from vegetables is simply to eat more of them. Short of rolling them in doughnut crumbs and deep frying them, pretty much anything that encourages you to eat more veggies is fair game. When you come across hydroponics that are fresher or cheaper or more appealing, there’s no reason not to take advantage of that! I certainly do. But don’t get between me and my garden when it’s time to pull those carrots out of the dirt.
Let me know what you think about hydroponic vegetables in the comments below or on the Nutrition Diva Facebook page.
Image courtesy of Shutterstock.
About the Author
Monica Reinagel is a board-certified licensed nutritionist, author, and the creator of one of iTunes’ most highly ranked health and fitness podcasts. Her advice is regularly featured on the TODAY show, Dr. Oz, NPR, and in the nation’s leading newspapers, magazines, and websites. Do you have a nutrition question? Call the Nutrition Diva listener line at 443-961-6206. Your question could be featured on the show.