Let's take a scientific look at the pros and cons of owning houseplants.
1.The " You Can Grow Your Own Fresh Air" movement.
This is the biggest and most lucrative selling point for online houseplant sellers in the last decade. But even though the "]Grow your Own Fresh Air" book by Wolverton was based on NASA research, the answer is really no. Fresh air is defined loosly in this book as trying to filter out unwanted toxins from the home and adding oxygen. The bottom line here is that in the average home you would need an extraordinary number of plants to make a dent in air quality. Effects are very local, so at your desk with several large green plants at your side, yes, the oxygen levels might be higher, and the carbon dioxide levels lower.The humidity might also be improved in winter months if you choose a plant like a pothos which transpires a lot. But the actual number required to do the job and size needed for each of the 50 plants listed in this book is one very significant and often overlooked variable.
2. The overstated mental health benefits.
Based on the philosophy that plants improve wellbeing,the monstera,pothos,asparagus fern, dracaena, and the highly fussy "lipstick plants are all cited online as good for mental health.
There is no data cited online, so let's look for a bit of data.
Studies have shown green plants do a better job of making us feel cheerful and also relaxed.
Flowers which are purple, green, red. pink and white lower blood pressure and heart rate.
Red and yellow roses have a more calming effect than white roses.
The number of plants in a room affects the strength of positive emotions for subject present. Five plants is good, or a five foot tall potted plant or three plus floral displays will do the job.Whiteish green leaves do the opposite.
These studies are wobbly in the sense that we have no idea who the subjects in the study are, their age, sex, education, willingness to participate, etc etc...Etc.
But there is some evidence that owning a plant or five of the correct color is a good idea.
Observations over a decade have taught us at our nursery that owning a plant which is not thriving is a source of stress and anxiety. So healthy plants are needed for the mental wellness argument for plant ownership.
3. Pesticides and herbicides.
The plants you buy from the big sellers depend on one thing:Profits. They are usually not owned by plant lovers. They could be owned by an insurance group. Money is needed to pay the shareholders. This impacts you, the online plant buyer in a very serious way. The big sellers need their plants to do two things:grow quickly, and sell quickly. These are perishable commodities. They must not die, so the big sellers do this by dressing employees in hazmat suits and spraying whatever herbicides and pesticides the FDA will allow them to spray.
On foods, the ingredients must be listed. On plants you buy, the pesticides and herbicides on the plants you carry into your home is an unknown list of potentially harmful chemicals.
Summary sheet of pesticides etc.
Here is a summary sheet from one of the biggest sellers in America.A set of hazard sheets is posted on a board each day because the employees spray the plants with herbicides,pesticides and fungicides.
You will notice that "Slugfest" was sprayed on their "Marble Queen" plants. These are a newish form of pothos, delicate and obviously a tasty treat for a slug.
Marble Queen pothos
Slugfest is metaldehyde. Warning labels from Orcal, its manufacturer, goes like this:
2.2.1 Hazard Statement(s): Harmful if swallowed Harmful in contact with skin Harmful if Inhaled Harmful to children and fatal to domestic animals when ingested.
Aquatic toxicity is also recorded.And your pets are not safe from this chemical.
After ingestion, metaldehyde is converted to acetaldehyde. Acetaldehyde is toxic to the nervous system and causes muscle tremors, ataxia (lack of coordination) and seizuresin dogs.Increased muscle activity leads to hyperthermia (high body temperature): another common symptom. Metaldehyde toxicity can lead to disseminated intravascular coagulation, multiple organ failure, and death. Within minutes, poisoned animals may show clinical signs. Symptoms may also be delayed and later develop up to three hours after ingestion.
These sort of chemicals are hazards needing masks, sometimes overall suits, occasionally hazmat suits. In the case of Slugfest, it's water resistant. That is, hard to wash off. So you're buying it.
Clearly plants from this nursery are protected from potential harm using daily sprays. Some of these remain on the plants and in the soil which comes with the plants. That is, you're buying not just plants, your buying plants plus everything sprayed on them. Bottom line, to keep unknown chemicals out of your home, buy from small independent nurseries with no shareholders breathing down the necks of the growers to maximize profits by spraying on the houseplants everything the EPA will allow.
Comments