If you think applying Seasol to your plants is enough to feed them - think again! There are a few big differences between fertilisers and seaweed health tonics that mean both are necessary for happy plants. Here's the dirt.


Fertilisers come in various forms, including slow-release prills and fast-acting liquids.



Much like humans and animals, all plants require food - it's just the manner in which we receive it that differs. Specifically, plants require adequate levels of the essential macronutrients nitrogen, phosphorus and potassium, which are found naturally in soil to a certain degree, but which require topping up to keep the plant healthy. All plant and garden fertilisers contain these three elements in different ratios depending on each plant's needs - look for the NPK on the container, and click here to learn more about the science behind them. Visit your local Flower Power Garden Centre and you'll find a broad range of fertilisers to suit all plants in a great selection of different formulations including liquids, soluble powders, slow-release prills, pellets and natural forms such as composts and manures.

When should I use a fertiliser?

Fertilisers should be used when your plants most need nutrients. There are a few occasions when this might become particularly apparent.

  • For potted plants, when the fertiliser included in your potting mix has been used up (check the packaging, but usually 3-6 months post planting) - ideally, you'll top up with slow-release fertiliser.
  • Regularly during growing season, especially for flowering and fruiting plants - liquid fertiliser plays a valuable role here.
  • At the end of winter, when your garden is beginning to wake up from hibernation mode.
  • When preparing a garden bed for planting - this is when forms such as compost and manure come in most handy.
  • After heavy rain, to replenish nutrients that might have leached from the soil.

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Seasol is one of the best-known seaweed health tonics on the market.


Seaweed health tonics

Seaweed solutions are a popular additive for plants - but they're not a substitute for fertiliser. Instead, you should think of them as a health tonic for your plants. Why? Seaweed tonics, such as Seasol, contain seaweed derivatives that work to condition your soil and improve its structure by increasing the levels of a range of micronutrients that occur naturally in the soil while also stimulating the growth of microorganisms . These elements are vital to your soil's microbiome and help to improve your plant's ability to take up the necessary nutrients, contributing to its overall health and resilience. What seaweed solutions don't include is the essential macronutrients - that is, nitrogen, phosphorus and potassium - in a strong enough concentration to sustain your plant's life, and therefore can't be considered a "plant food". Seaweed tonics should be considered an essential part of your gardening regimen, alongside a suitable fertiliser.

When should I use a seaweed tonic?

Seaweed tonics are particularly useful in a few different scenarios.

  • Use when repotting or replanting to help prevent transplant shock.
  • Use during or after extreme weather conditions to help plants cope with heat stress or frost damage.
  • Apply to new and establishing plants and seedlings to help enhance root growth.
  • Apply during the growing season of ornamental and fruiting plants to stimulate production.
  • Use when signs of pest, disease and fungus are evident to help combat ill-effects.
  • Got a sick plant? Apply weekly for 6-8 weeks to help it bounce back.

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