Fertiliser and compost: When to use what

Gardening is a science as much as an art. Without a working knowledge of gardening products and plant nutrition solutions, a gardener is bound to run into trouble bringing their outdoor vision to life. If you’re a novice green thumb, we bet you know what we’re talking about!

Underproductive vegetable gardens, lacklustre flower beds, slow plant growth, weed takeovers. Does any of this sound familiar? If you’re thinking, yes, I can relate, the Wonder experts are here to get you clued up on gardening nutrition solutions. Starting with the building blocks of any garden – soil and plant nutrition. (Browse our range of quality fertilisers online.)

What’s the difference between fertiliser and compost?

First thing’s first. Unpacking the product definitions. Fertiliser and compost serve entirely different purposes in the garden. So no, they are not interchangeable. In a nutshell, fertiliser feeds the plants and compost feeds the soil. But let’s explore the differences in more detail together.


Fertiliser is natural and synthetic chemical substances combined in a mixture to increase the fertility of soil. The nutrient profile of fertiliser is specifically geared towards the health of plants, and not the soil’s food web itself. It is often a specialised concentrate that caters to the needs of specific plant varieties, helping them grow and flourish, and recover during periods of stress. Unlike compost, fertiliser should not be applied in excess. I.e. If a plant requires assistance, help it with fertiliser. Explore our wide range of fertilisers online.


Compost, on the other hand, is a mixture of natural organic compounds, decomposed to silt, and rich in nutrients and beneficial organisms. It is also used to increase soil fertility, but this time for the benefit of the soil itself, and not the plants. (Though the nutrients in compost are helpful to plants too.) Because of its natural composition and ongoing benefit to the soil food web, compost can be applied to the garden whenever and wherever for general soil maintenance. Basically, you can never use enough compost! Check out our expertly formulated fertiliser and compost solution, Wonder Organic Vita-Boost Vermicompost.

When to use fertiliser and compost

Ready-to-use fertiliser and compost the right way? Here are some tips to get you started on your garden nourishment journey:

If you’re ready to get planting, choose fertiliser

It’s wise to apply a fertiliser targeted at your plants’ needs before you establish them in the soil. The right fertiliser will give them the kick of nutrients they need to grow into healthy little plants. And become big, fully grown plants that much faster (Explore our range of plant-starting fertilisers.)

If established plants need a pick me up, choose fertiliser

Plants with special needs or deficiencies may need additional enrichment from time to time. Applying a fast-release fertiliser rich in the micronutrient the plant is lacking will help it recover and perform at its best. Calcium, potassium, magnesium and phosphorus, for example, are often lacking in garden soils, so may need to be supplemented.

If your soil is of poor quality, choose compost

Regardless of your plant types and their preferences, your soil needs to be of a basic good quality in order for anything to grow. If it’s dry, compact, or of a consistency that’s generally unfriendly to plants, grab a shovel and give it a good turn, then apply a layer of compost. Good soil quality is essential to the health of any garden.

If you want to give your garden extra love, choose compost

As we suggested earlier, the more compost applications, the merrier! Any time you feel like giving your garden a little extra TLC, go to town with a generous layer of compost. Your plants will thank you!

Wonder Organic Vita-Boost Vermicompost contains top-quality vitamins, nitrogen, iron, manganese, and other important components specifically designed to increase growth rates, vigour and quality in vegetables, flowers, and fruit trees. Also helps rejuvenate poor soils, water retention, increases the number of beneficial bacteria and develops soil structure for better root growth.

Make our fertiliser and compost solutions your own

Want to reap the rewards of a beautiful outdoor space? Fill your garden with Wonder. Take advantage of our wide range of fertiliser and compost solutions, available in garden centres, nurseries, and leading outlet stores nationwide.

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