Liquid & powder
NPK Fertiliser
Balanced NPK 20-20-20 for growth, NPK 4-18-38 for flowering and fruiting. Liquid or water-soluble powder. Made in Australia.
Liquid: ready to measure and mix, good for pots and home gardens.
Powder: the economical pick for bigger gardens, market gardens and commercial growers. Sizes from 500 g to 20 kg.
- Free shipping Australia-wide
- Made in Australia
- Grower help (02) 9053 1426
Products
Nothing matches that combination yet
All Purpose Plant Liquid Fertiliser – Formulated from NPK 20-20-20 & Micro Nutrients
Choose a size
Liquid
24All Purpose Plant Liquid FertiliserFormulated from NPK 20-20-20 & Micro Nutrients
Balanced · every stage
NPK 20-20-20 Powder Soluble Nutrient Plant Fertilizer & Micro Nutrients
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Powder
15NPK 20-20-20 PowderSoluble Nutrient Plant FertiliserWith Micro Nutrients
Balanced · every stage
Advanced Formula - Boost Flowering & Fruiting - NPK 4-18-38 + Calcium & Magnesium
Choose a size
Powder
17Advanced Formula for
Flowering & FruitingNPK 4-18-38 + Calcium & Magnesium
Strong bloom · from budding on
Citrus Fertiliser – Lemon, Lime & Orange Tree - NPK 6-2-12 + Trace Elements
Choose a size
Liquid
13Citrus FertiliserFor Lemon, Lime & Orange TreesNPK 6-2-12 + Trace Elements
Slight bloom · leaf and fruit
Liquid · Hose-on
9Lawn Grow Hose-OnLiquid Lawn Fertiliser (2L)For a Greener, Thicker Lawn
Strong leafy · leafy green growth
Hydroponic Nutrients Fertilizer – Two-Part Formula (A & B)
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Liquid · 2-part
10Hydroponic Nutrients FertilizerTwo-Part Formula (A & B)Complete base nutrient system for hydroponic growing
Two-part A + B formula
Balanced · full grow cycle
Cactus Succulent Plant Food Fertiliser Concentrate
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Liquid
7Cactus Succulent Plant Food Fertiliser Concentrate
Slight bloom · leaf and fruit
Indoor Plant Food Concentrate Fertiliser 100ml Makes 100 Litres
Choose a size
Liquid
5Indoor Plant FoodConcentrate Fertiliser 100ml Makes 100 Litres
Slight leafy · leaf and flower
Liquid · 2 × 500 mL
Orchid Grow & Bloom DuoLiquid orchid fertiliser for leaves, roots and flowers2 × 500 mL concentrates · Makes 1,000 L
Grow first, then Bloom when spikes appear
Liquid or powder NPK fertiliser?
Liquid or powder NPK fertiliser?
NPK stands for nitrogen (N), phosphorus (P) and potassium (K), the three nutrients plants use most. The numbers show the percentage of each: NPK 20-20-20 is an even, balanced feed, while NPK 4-18-38 is low in nitrogen and high in phosphorus and potassium.
NPK 20-20-20 is the everyday feed for leafy growth, vegetables, shrubs and fruit trees while they’re growing. Choose All Purpose Plant Liquid Fertiliser in 1 L, 4 L or 20 L, or NPK 20-20-20 Water-Soluble Powder in 500 g, 3 kg, 4.5 kg or 20 kg for watering cans and hose-end sprayers.
NPK 4-18-38 takes over when plants start budding, flowering and fruiting. Advanced Formula is a three-part system (NPK 4-18-38, calcium nitrate and magnesium sulphate) for fruiting and flowering plants in soil or hydroponics, in 1 kg, 4 kg, 10 kg and 20 kg.
Not sure which ratio you need? Read our guide to using NPK 20-20-20 at every plant stage, or call (02) 9053 1426.
Which NPK fertiliser do I need?
Match the NPK ratio to what the plant is doing: NPK 20-20-20 while it grows, NPK 4-18-38 while it flowers and fruits, and NPK 6-2-12 for citrus.
NPK 20-20-20
Liquid · 1 L, 4 L, 20 L
Leafy growth in pots, home gardens, vegetables, herbs, shrubs and indoor plants.
NPK 20-20-20
Powder · 500 g to 20 kg
Bigger gardens, market gardens and commercial growers using watering cans and hose-end sprayers.
NPK 4-18-38
Powder + Ca & Mg · 1 kg to 20 kg
Budding, flowering and fruiting plants in soil or hydroponics.
NPK 6-2-12
Liquid · 1 L, 4 L, 20 L
Lemon, lime, orange and mandarin trees, with added trace elements.
What N, P and K do
N · Nitrogen
Builds leaves and stems and keeps foliage green. The main nutrient for growth.
P · Phosphorus
Drives root growth, flower buds and the energy plants use to flower and set fruit.
K · Potassium
Improves fruit size, flavour and flower quality, and helps plants handle heat and dry spells.
NPK fertiliser FAQs
What is NPK fertiliser?
NPK fertiliser is a plant food that supplies nitrogen (N), phosphorus (P) and potassium (K), the three nutrients plants use most. The three numbers on the label, such as 20-20-20, show the percentage of each.
What is the best NPK ratio for plants?
Use a balanced NPK 20-20-20 while plants grow leaves, stems and roots, then switch to a high-potassium NPK 4-18-38 when they bud, flower and fruit. Citrus trees do best on a dedicated citrus formula such as NPK 6-2-12 with trace elements.
Is liquid or powder NPK fertiliser better?
Both supply the same nutrients. Liquid is ready to measure and mix, so it suits pots and home gardens. Water-soluble powder is the economical pick for bigger gardens, market gardens and commercial growers.
Can I use NPK 20-20-20 on all plants?
NPK 20-20-20 suits vegetables, herbs, shrubs, fruit trees and indoor plants while they are actively growing. Switch to NPK 4-18-38 at flowering, and use a specialist feed for orchids, cactus and lawns.
Do you deliver NPK fertiliser Australia-wide?
Yes. CompleteGrow NPK fertilisers are made in Australia, with free shipping Australia-wide. For help choosing, call our grower line on (02) 9053 1426.
