April 5, 2023

What's the difference between compost and fertiliser?

To even a well-seasoned gardener, the difference between compost and fertiliser can sometimes be murky. Fear not – we’re here to help.

What exactly is compost?

You may have perfected your composting for your garden or farm, or perhaps your only exposure to compost is when you had that infamous classroom compost bin in primary school.

To make sure we’re all on the same page, compost is broken down organic matter. You add a bunch of organic matter to a bin, such as kitchen scraps and dead leaves, and eventually bacteria find this jackpot (well, jackpot for them) and break it down.

The decomposed organic matter then turns into compost, which looks exactly like soil to the untrained eye. While it may seem like broken down leftovers and dead leaves would be pretty useless, this is far from the case. Compost can be a pretty powerful ingredient to your garden. Simply put, it provides organic matter to the soil, which among other things improves soil structure and health.

However, fertiliser is something quite different.

What makes fertiliser different?

The key difference between compost and fertiliser is that fertiliser is a substance that primarily feeds plants the key macronutrients it needs – nitrogen, phosphorus, and potassium (NPK). While compost provides organic matter to the soil, fertiliser is primarily concerned with providing the necessary nutrients for the plant to grow. Compared to fertilisers, compost contains low amounts of these nutrients for plants.

So while compost definitely has a place in a healthy garden, when your plants need nutrients for growth then fertiliser is what you’re after. In fact, a lot of plants simply will not grow without fertiliser. Without the three building blocks of plant life – nitrogen, phosphorus, and potassium – plants cannot grow properly, and fertiliser is really the only way to deliver these nutrients in high enough concentrations for adequate growth.

The best of both worlds

Okay, so compost feeds the soil and fertilisers feed the plants. But does it need to be separate like this?

We don’t think so. In fact, we know it doesn’t need to be.

Organic fertilisers are derived from organic matter, but have NPK values that qualify it as a fertiliser. So alongside having nutrients that are fed to the soil, they also contain the organic matter that is so important for soil health. Talk about a great one-two combination!

At Bardee, our organic fertiliser Superfly is 100% black soldier fly frass. In our world-leading vertical farming system, black soldier fly larvae transform food waste into incredible organic fertiliser. Superfly has NPK values that make it an incredible choice to deliver nutrients to your plants.

The benefits don’t just stop there. Superfly is also chock-full of beneficial microbes (240 million microbes per gram to be precise! 🤯), which do everything from stimulating plant growth to cycling plant nutrients and breaking down organic matter. And if that wasn’t enough, Superfly contains chitin, a pretty special ingredient that helps plants grow, fights off diseases, and germinates seeds.

Want to know more? Head over to our website to get in touch with us and find out more about the magic of Superfly!

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