Planting myths often contain a seed of truth, but as any gardener knows, the real story is rarely so simple. In gardening, there’s rarely a one-size-fits-all rule. What works in one garden, climate, or soil type might be a disaster in another.
Let’s talk horticultural myths and gardening “truths” that aren’t quite right…
What have you believed or done in the garden that turned out to be misunderstood, outdated, or just plain wrong? Here are a few confessions to get us started:
Myth
Potting mix feeds your plants for 18 months
When potting mix says “feeds for 18 months,” that’s from the date of manufacture, not the day you open the bag. And no… they don’t put the date of manufacture anywhere on the packaging.
That’s why we always recommend feeding when planting, using something like Organic Link so you know exactly when the last feed happened. If in doubt, reapply every three months or with the turn of each season to keep nutrients consistent.
Myth
Full sun means all-day blazing sun
When a plant label says “full sun,” it simply means the plant needs at least 6 hours of direct sunlight per day. But not all sun is created equal.
Ipswich sun in December is a whole lot fiercer than Melbourne sun in December. So generally, if a plant tag says “full sun,” aim for sun-up to midday in hot climates — that’s a safe six hours for most plants.
And here’s the kicker: some plants can handle 12+ hours of blazing sunlight a day and thrive in it. Unfortunately, they’re labelled exactly the same as more delicate “morning sun only” plants. No wonder it gets confusing!
This is exactly why plant labels aren’t your only resource. Chatting to your local garden centre and their qualified horticulturists is the best way to get location-specific advice based on real experience.
Myth
Banana peels are a great potassium fertiliser
Banana peels just don’t have enough potassium in the peel to make much difference when used directly on your garden.
Let’s break it down: banana peels contain about 78mg of potassium per 100g, while a proper potassium fertiliser contains thousands of milligrams per application, plus it’s in a form that plants can actually absorb.
So while it sounds lovely to tuck a banana peel under a plant, you’re better off adding it to your compost where it can break down with other organic matter and contribute to long-term soil health.
If your plant needs potassium? Reach for a specific potassium-based fertiliser like Sulphate of Potash or Silica and Potash, especially during flowering and fruiting seasons.
The takeaway?
Read the label. Read your climate. And talk to someone who’s been there, killed that, and figured it out the hard way!
Have a gardening myth you’ve fallen for — or one you’re not sure about? Pop in and see us at Trevallan, or drop a comment below. We’d love to help you sort fact from fiction.
I’ve recently covered a few more myths you might like to explore
Check them out and keep growing smarter!