One of the most widely available fertilizer products on the market today is Miracle-Gro. The water-soluble fertilizer works wonders with flowers and shrubs. The efficiency of this product had me wondering: Is it safe to eat vegetables grown with Miracle-Gro? Here’s what I learned from my research.
It is safe to eat vegetables grown with Miracle Gro but you need to wait at least two weeks after application of the chemical fertilizer so it’s absorbed by the plants. You should also wash the vegetables well before you eat them as the chemicals can irritate the mouth, throat, and skin.
I’ve written a lot more research below that will help you understand how to use Miracle-Gro safely and take necessary precautions when using vegetables grown with this fertilizer.
Is it Safe to Eat Vegetables Grown with Miracle-Gro?
Miracle-Gro is a unique product that gets a bit of a bad rep with the gardening community when it comes to edible plants. It’s not hard to see why. It’s a synthetic fertilizer.
That means that the nutrients you’re feeding your plants come from man-made inorganic compounds. They’re often referred to as chemical fertilizers, which always come with a bad connotation.
Ask any gardener and they’ll tell you that organic fertilizers are always better. But what if you don’t have access to compost or other types of organic fertilizer? Products like Miracle-Gro aim to bridge that gap.
The truth is, your plants don’t care where they are getting their nutrients from. They’ll take advantage of it either way.
The All-Purpose Plant Food fertilizer contains many of the nutrients your plants need to thrive. At its core, it’s a basic 24-8-16 fertilizer. That means it contains 24 percent nitrogen, 8 percent phosphorus, and 16 percent potassium.
The remaining 52 percent is trace elements.
According to Miracle-Gro, the All-Purpose formula is completely safe for vegetables. As long as you use the product as directed, you shouldn’t encounter any issues. The fertilizer contains no known carcinogens, making it safe for humans.
If you are on the fence because it’s a synthetic product, you have some other alternatives. Miracle-Gro is most-known for its water-soluble formula, but the brand also has an organic line and products for vegetable crops.
Like the standard plant food, those fertilizers are perfectly safe for vegetable plants.
When Can I Eat Vegetables After Applying Miracle-Gro?
One of the biggest concerns with synthetic fertilizers is how chemical ingredients can affect human health.
Miracle-Gro is pretty transparent about some of the issues that come with using the product.
The fertilizer is a powerful product that can cause immediate discomfort on the skin. Touching plants or vegetables that have fresh fertilizer could lead to skin rashes. Ingesting it results in even worse complications.
Miracle-Gro contains urea. Urea can cause irritation in the mouth, throat, and stomach if accidentally ingested or swallowed. Urea is a naturally occurring substance. But in fertilizers, it usually comes from ammonia. As a result, it’s incredibly dangerous when consumed.
Needless to say, you should never eat vegetables immediately after applying Miracle-Gro. You have to give the plant some time to fully process and use the nutrients in the fertilizer to ensure that your harvest is safe.
This short time frame is a big difference from organic fertilizers. With organic products, you have to wait for the fertilizer to decompose before the plant can use it. That can take upwards of six weeks.
Many gardeners instinctively stop applying fertilizer when the plant starts producing vegetables. But, you should continue using it to ensure a bountiful harvest.
As long as you wait two weeks after your last application to harvest, the fertilizer should be long gone. Of course, make sure to give the vegetables a good washing to ensure that no product is leftover.
Does Miracle-Gro Have Any Long-Term Effects on Human Health?
Currently, there are no studies on the long-term effects of using Miracle-Gro. Regularly consuming vegetables fertilized with Miracle-Gro won’t have major long-term effects.
That said, continually using Miracle-Gro could change your soil. This is where the concern lies.
Negative Impacts of Miracle-Gro
Organic fertilizers benefit the microorganisms living in the soil. They don’t just improve plant quality. It’s a full cycle that can continually improve soil quality over time.
Synthetic fertilizers can kill those microorganisms. Those tiny creatures are responsible for converting organic matter into usable energy for your plants. When you use synthetic fertilizers, you’re eliminating them and making your soil worse in the long-run.
As a result, you’d have to rely on the fertilizer even more to grow plants.
Not only that, but synthetic fertilizers can pollute the environment. As we mentioned earlier, most of the nutrients leach into the soil.
They can make their way to the groundwater and eventually run into nearby streams or lakes. The excess nitrogen can then kill fish by depriving it of oxygen.
Effects on Human Health
Even if you’re not concerned about environmental factors, Mother Nature always finds a way to tie it back to humans.
When the synthetic nutrients get into groundwater, it contaminates the drinking supply. The fertilizer raises the levels of nitrates and nitrites. Consuming those compounds can lead to severe hemoglobin disorders like Methemoglobinemia.
All of these potential health issues come from the results of repeated use of synthetic fertilizers like Miracle-Gro. The risks are lower significantly in small backyard gardens. But, large-scale applications could be risky in the long-run.
Is Miracle-Gro a Good Fertilizer for Vegetable Plants?
Ultimately, using synthetic products like Miracle-Gro is a personal decision.
Technically speaking, it’s great for vegetables. The basic composition of nutrients can benefit your plants.
The phosphorus and nitrogen will help foliage flourish and help convert other nutrients into usable energy. Meanwhile, potassium resists disease and strengthens the plant. If you get a vegetable-focused formula, it’ll have calcium to help provide a better yield.
But, you can’t ignore the potential negative health and environmental effects that come with using it long-term.
Miracle-Gro on plants is still a point of contention among gardeners. Some swear by it while others will tell you that you should avoid synthetic fertilizers at all costs.
A good middle-ground would be to use Miracle-Gro on container plants only. By using the product on contained vegetable plants, you reduce your risk of environmental damage. This can lower your risks of contaminating your water supply and experience long-term health issues, too.
How to Apply Miracle-Gro to Vegetable Plants
Using Miracle-Gro is very easy. This is a product that doesn’t take a ton of time to prepare like organic compost.
Dissolving the Fertilizer
The first step is to dissolve the fertilizer. This is very important. When applying the granules as is, you run the risk of burning the plant. You must dilute the solution so that the nutrients are safe for the plant to use.
Just follow the instructions on the package to prepare the liquid fertilizer. For the All-Purpose Plant Food, you just add 1 and a half tablespoons of the water-soluble fertilizer to 1 and a half gallons of water.
Let the fertilizer dissolve fully and apply it to the soil at the base of your plant.
Using Miracle-Gro as a Foliar Spray
Miracle-Gro also works well as a foliar spray. With this application method, you’ll use a garden feeder spray.
The mixture is usually the same: 1 tablespoon to 1 gallon of water. However, there might be some variations based on the design of your sprayer. Follow the directions closely.
Apply the spray directly onto the plan leaves. It’s best to do this in the early morning when the air is cool. Don’t attempt to spray the plants in the hot sun. The plant will not be able to absorb the nutrients.
How Often to Apply Miracle-Gro to Vegetable Plants?
Generally, you can apply Miracle-Gro every 1 to 2 weeks. I recommend sticking to a simple 14-day fertilization cycle for simplicity.
14 days is more than enough time for the plant to absorb and process the nutrients. Reapplying the fertilizer will promote continued growth. Keep applying the fertilizer even after your plants start producing fruit.
Of course, always keep a watchful eye. It is possible to apply too much.
When you over-fertilize plants, they could focus their attention on developing more leaves or stems. This could lead to a poor root structure and small yield.
If your plant continues to grow without producing any fruit, consider holding back on reapplications. You may also want to think about pruning the plant to refocus its energy on fruit production.