Gardening terms
Plant food vs fertiliser.
Are they the same thing? In everyday gardening, yes. The differences that matter are somewhere else.
- The wordsMean the same
- What variesSource, speed, form
- Soil improverA different job
In everyday use, they mean the same thing
A plant food, a fertiliser and a feed are all something you give a plant to supply the nutrients it needs. Some gardeners use "fertiliser" for the stronger, faster-acting products and "plant food" for gentler ones, but it is not a strict rule, and packs use the words freely.
The differences that do matter
Whatever the word on the front, feeds differ in these ways. They are general distinctions in line with the RHS, and individual products vary.
| What is being compared | Made from living thingsplant or animal origin | Mined or manufacturedsynthetic or mineral |
|---|---|---|
| Where it comes from | Plants or animals, for example seaweed, comfrey, bone or manure. | Mined or made in a factory. |
| How concentrated | Usually less concentrated, and it can vary from batch to batch. | More concentrated. |
| How fast it works | Usually slower, especially dry forms that soil organisms must break down first. | Usually faster. |
| Good for | Steady feeding over time, and building soil as well as feeding the plant. | Quick results, and correcting a shortage. |
| Form matters too | A liquid acts faster than a dry pellet. | Coated granules can release slowly. |
Both kinds can be sold as liquids, granules, pellets or powders, and both are called feeds.
Four things people believe about feeding
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Myth
Plants eat fertiliser.
RealityPlants make their own food from sunlight, water and carbon dioxide. Fertiliser supplies the minerals they need to do that, closer to vitamins and building blocks than to a meal.
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Myth
Sunlight is plant food.
RealitySunlight is the energy source, not a nutrient. A plant needs both light and minerals.
-
Myth
More feed means faster growth.
RealityToo much gives soft, lush growth that is less resilient, can scorch leaves and can harm soil life. Feed is not a substitute for water or light.
-
Myth
Plant food is just a friendlier name for weak fertiliser.
RealityHow strong a feed is depends on the product, not the word on the front. Read the label for what it is and how to use it.
Plain-English terms
The words you will meet on labels, without the jargon.
- Feed, feeding
- Giving a plant nutrients. Applying a fertiliser is called feeding.
- Nitrogen
- Drives leaf and stem growth and green colour.
- Phosphorus
- Supports root and shoot growth.
- Potassium (potash)
- Supports flowering, fruiting and toughness in the cold.
- General-purpose feed
- Contains several nutrients to support leaf, root, flower and crop growth.
- Controlled-release
- Coated granules that meter nutrients out slowly over time.
- Soil improver
- Something dug in to improve soil structure, such as compost, leafmould or well-rotted manure. It works on the soil, not directly on the plant.
- Mulch
- A layer at least 5 cm thick laid on the soil surface.
What we mean by plant food
We use "plant food" across our range, for liquid feeds made on our family farm in Cumbria from what the farm's renewable energy process leaves behind. We call the solid a "soil improver", because that is its job: it prepares the ground rather than feeding a growing plant.
We do not have side-by-side trial results to share, so we will not claim that one kind of feed beats another. What we can tell you is where ours comes from and how to use it, and that is on every label. Our guide to what natural plant food is goes into the source.
Questions people ask
Is "plant food" just marketing for fertiliser?
Not necessarily. In everyday use the two words mean the same thing, and the RHS treats them that way. Some gardeners draw a looser line between a gentler, plant-based "plant food" and a more concentrated, faster "fertiliser", but it is not a strict rule either way.
Does it matter which word is on the packaging?
Less than what is in the product and how to use it. Look at what it is made from, what it is for, and the directions on the label.
Is a soil improver the same as a fertiliser?
No. A soil improver works on the soil over time, improving its structure and how it holds water and nutrients. A fertiliser works on the plant this season. Most gardens benefit from both, in different amounts.
What are the numbers on a feed pack?
Packs show headline numbers for the three main nutrients, nitrogen, phosphorus and potassium. They tell you the balance, for example a feed higher in potassium for flowers and fruit. The figures are not always like for like between packs, so compare with care.
Why make five products instead of one general feed?
So you always know which to reach for. Five products, five colours, one job each: houseplants, flowering plants, fruit and veg, lawns and soil. Each label has its own directions.
