Fact or fiction? Addressing common claims about gardening
It's easy to get lost among the thousands of videos offering "can't-fail garden tips."
Ever wander through social media sites and wonder if you can really propagate roses by inserting cuttings into a tomato? Or if that “magical DIY fertilizer” is real? It’s easy to get lost among the thousands of videos offering “can’t-fail garden tips.”
Just how much scientific research goes into these instant success stories?
Let’s examine some of this advice:
“Place one piece under the orchid. It will grow 100 branches and bloom all year-round.”
The “piece” referred to here is a banana peel. The recipe involves fermenting a banana peel with molasses in water then using this liquid as a “magic” organic fertilizer.
Banana peels are actually beneficial to the garden when they are added to your compost. No need to slice and dice and wait three weeks for the magic to brew. Just toss the peels into your home compost bin or add to your green can.
“Use watermelon peels to make organic liquid fertilizer.”
No magic required: Add watermelon rinds to your compost. Or invert melon rinds and place in your garden as traps for snails and slugs. Scrape off the accumulated snails and slugs daily and destroy them.
“Water orchids with ice cubes” and “fertilize your orchids with a solution of rice water and garlic (or ginger).”
Ice cubes continue to be a controversial topic. Many online sites recommend that three ice cubes, once per week, offer the proper amount of moisture and prevent overwatering.
Orchids are tropical plants, and ice cubes can lower their temperature. It has been shown that ice cubes can harm the leaves and lead to crown or root rot over time. Water your plant “weakly weekly.” Once a week, water with half- or quarter-strength balanced, urea-free orchid fertilizer, allowing the water to flow through the pot. Do not leave the plant sitting in a puddle.
Numerous social media posts promote using your pasta cooking water to water plants. Most cooks salt their pasta water rather heavily; some chefs say, “Pasta water should be as salty as the sea.” The amount of salt in the water could be unhealthy for your soil and cause wilted or stunted growth. Even in a drought situation, watering plants with heavily salted water is not recommended.
“Chemical free”
Really? And what would that be? Everything that exists is composed of chemicals — water, air, plants, our bodies — all composed of chemicals.
This term is frequently used in marketing to make us feel secure that the product is healthy, safe, free of toxins or environmentally friendly. But, it is not chemical-free.
Random garden advisors recommend “natural” weed control using common household products such as baking soda, vinegar or dish soap in a solution.
While these mixtures may not contain toxic chemicals, none of these products successfully kill weeds, but they can add a significant amount of sodium to the soil. Mulch garden areas well to inhibit the growth of weeds while also improving soil structure and providing other benefits.
Watching videos of interesting characters presenting gardening tales passed down from their grandma or picked from other social media sources can be a fun way to fill the day and plan an “instant” and “magical” garden. Still, there’s a better and more reliable channel. Spend some time on the Marin Master Gardeners’ YouTube channel at youtube.com/c/UCMarinMasterGardeners. Science-based gardening advice is scripted, fact-checked, staged, filmed, edited and presented by UC Marin Master Gardeners. Recently released topics include Earth-friendly gardening, advice for planting natives and succulents, and how to attract birds to your garden. More than 30 timely videos will help you learn about the best practices for gardening in our Mediterranean climate.
Take a spin around our recently redesigned website, marinmg.ucanr.edu, which offers tips on selecting plants for Marin’s microclimates, seeding, soil prep, irrigation and much much more.
Sponsored by UC Cooperative Extension, the University of California Marin Master Gardeners provides science- and research-based information for Marin home gardeners. Email questions to helpdesk@marinmg.org. Attach photos for inquiries about plant pests or diseases. Please call 415-473-4910 to see when a master gardener will be at the office or drop off samples 24/7 in the sample box outside the office. To attend a gardening workshop or subscribe to Leaflet, a free quarterly e-newsletter, go to marinmg.ucanr.edu.