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GREEN24

Rhododendron & Azalea Fertiliser

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Liquid NPK concentrate for acid-loving plants

Regular price €9,85
Regular price Sale price €9,85
Unit price €39,40/L
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This pack makes approx. 125 l of ready-to-use fertiliser for rhododendrons and azaleas.

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Quantity
Volume discount & item detailsVolume discount · More information about your selected pack
SKU: RHW50K90F10

250 ml

Makes 125 litres of prepared fertiliser solution · at the label dosage

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3+ units−5 %
5+ units−7 %
10+ units−10 %

Per fertiliser type; pack sizes can be combined. One twin pack counts as one unit. The discount is applied automatically at checkout.

Clusters of spring flowers give an ericaceous border its character. Feed rhododendrons and azaleas with their needs in mind, while keeping the root zone acidic and consistently moist.

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Quality products Horticultural expertise Our own production Made in GermanyGREEN24's own products

A favourite green space

A garden moment filled with flowers.

From a compact azalea to a large rhododendron shrub, flower colour, foliage and habit create very different garden scenes. Suitable soil and a sheltered position provide the foundation; fertiliser supplements nutrients during growth.

Declared NPK
2.5 + 4.0 + 6.0With declared trace nutrients.
Dilution
5 ml per 2.5 l of waterEvery 2–3 weeks during the growing season.
Application
Roots & foliageDilute with water before use.
Regular application period
April/May–SeptemberApply only during active growth.

Does this fertiliser suit your plant?

Identify your plant

For rhododendrons, azaleas and the other acid-loving plants listed by the manufacturer. An indoor azalea needs different care from a hardy garden shrub.

Use during growth

Every 2–3 weeks during growth; regular application period April/May to September.

Consider the root zone

An acidic, humus-rich root zone and dappled shade suit many garden forms. Use rainwater and monitor root-ball moisture. Fertiliser does not automatically turn alkaline garden soil into an ericaceous bed.

Easy application

Rhododendron and Azalea Fertiliser: correct dosage

Enter your water volume or estimate the amount from the size of your plant.

More calculations & plant age

Enter the water volume in litres. The calculator works out the concentrate needed. View application

Approximate amount of water10 L
Add concentrate20.0 ml

Shake well before use. Add the concentrate and mix thoroughly.

Dilution: 5 ml per 2.5 l of water.

Product information

Application & dilution5 ml per 2.5 l of water

5 ml per 2.5 l of water.

Every 2–3 weeks during the growing season.

Regular application period: April/May–September.

  • Do not use undiluted. Shake well before use.
  • Preferably use low-lime water or rainwater at 15–25 °C.
  • Do not apply in direct sunlight or at temperatures below 5 °C or above 30 °C.
  • Apply to a pre-moistened root zone or spray the foliage. Do not spray open flowers.

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PropertiesProduct characteristics and guidance

Net mass: 281 g for 250 ml; 1125 g for 1 litre.

The dilution is the same for both pack sizes.

Nutrient compositionNPK 2.5 + 4.0 + 6.0

Declared nutrient percentages. Product pH: 6.8.

  • 2.5% total nitrogen (N)
  • 2% urea nitrogen
  • 4% water-soluble phosphate (P₂O₅)
  • 6% water-soluble potassium oxide (K₂O)
  • 0.005% boron (B)
  • 0.002% copper (Cu) · EDTA chelate
  • 0.03% iron (Fe) · EDTA chelate
  • 0.006% manganese (Mn) · EDTA chelate
  • 0.0005% molybdenum (Mo)
  • 0.002% zinc (Zn) · EDTA chelate
Mixing with other productsMixing, combining or applying separately

Using products as part of the same care routine is different from mixing them in one container. Follow the labels and application instructions of all products involved.

  • Tank mixing: Combine products in a watering can or spray tank only when the manufacturer instructions confirm the specific combination and use. Do not mix undiluted concentrates together.
  • Separate application: Applying products separately or at different times does not automatically establish compatibility. Check the species, location, plant condition and instructions for both products. No universal waiting period follows from this.
  • Complementary products: A recommendation for suitable growing media, accessories or another care product does not mean that it may be mixed with the fertiliser.
  • Plant protection products: The crop, target organism, application method and pack instructions must also be suitable. The fertiliser calculator does not calculate plant protection product quantities or confirm compatibility.

The recommendations cover products for different care tasks. Combining them in the same solution requires the instructions for both products to allow that combination. Otherwise, apply the products separately.

Go to plant protection advice →

Rhododendron at a shaded garden edgeEnlarge image ↗

The plant comes first

A garden moment filled with flowers.

From a compact azalea to a large rhododendron shrub, flower colour, foliage and habit create very different garden scenes. Suitable soil and a sheltered position provide the foundation; fertiliser supplements nutrients during growth.

Measured concentrate is added to water in a watering canEnlarge image ↗

The correct mixture

5 ml per 2.5 litres of water.

One capful equals 5 ml. Use 6 ml for 3 litres of water at standard strength. Every 2–3 weeks during growth; regular application period April/May to September.

Calculate the required amount →
Mix, water or spray

Mix your fertiliser – step by step

Prepare the amount of nutrient solution you need. The dilution depends on this product and the required amount of water.

  1. Clean the container

    Clean the watering can, sprayer or bucket and rinse it with clean water.

  2. Calculate the dose

    Choose the amount of water you need and calculate the matching concentrate dose. The dosage calculator helps you do this.

    Dilution: 5 ml per 2.5 l of water

    Calculate the right amount →
  3. Add some water

    Pour part of the calculated amount of water into the container first.

  4. Shake, open & measure

    Shake the closed bottle well. Then open it and measure the calculated concentrate dose with the dosing cap. Measure more than once if needed.

    Measure the concentrate using suitable millilitre graduations.

  5. Add the concentrate

    Pour the measured concentrate into the water already in the container.

  6. Add the remaining water & mix

    Add the rest of the calculated water and mix thoroughly. Your diluted nutrient solution is ready.

Dosage and water choice

Shake well before use. Choose the volume of water and measure the calculated concentrate dose. Pack size does not change the dilution.

Preferably use low-lime water or rainwater at 15–25 °C. Add the measured concentrate to the water and mix thoroughly. Never apply undiluted; prepare only what you need.

When applying the solution

Check growth, growing-medium moisture and previous feeding. Feed only during active growth.

Regular application period: April/May–September

For root feeding, moisten dry growing medium with water first. Check drainage; the pot should not remain standing in water.

Distribute the diluted solution over the pre-moistened root zone or spray the foliage. Do not spray open flowers. Do not apply in direct sunlight, below 5 °C or above 30 °C. Do not inhale spray mist.

Follow the safety instructions →

Through the root zone

Apply the diluted solution to the pre-moistened root ball. Allow excess water to drain from containers; account for initial and additional feeds.

Through the foliage

Wet foliage according to the label and avoid open flowers. A foliar feed counts towards total nutrition and is not automatically added to root feeding.

Original product image: GREEN24 Rhododendron and Azalea Fertiliser, 250 ml with German front labelEnlarge image ↗

Feed roots and foliage

Choose the appropriate application method.

The label permits watering and spraying at the same dilution. Both routes count towards total nutrient supply. Avoid open flowers; a foliar feed is not an automatic extra portion.

Understand root and foliar uptake

Understanding plant feeding

How do nutrients get into a plant?

Through the roots or through the leaves: explore four steps to discover how a plant takes up and uses nutrients.

Select a point in the picture or choose a stage.

A look inside a rootEnlarged, simplified illustration

Stage 01 / 04

Water carries nutrients to the roots

Dilute the fertiliser with water according to the label. Watering carries this nutrient solution into the soil or growing medium around the roots.

Good to knowAlways dilute the concentrate and keep to the stated dosage.

A closer look

Watering carries dissolved nutrients into the growing medium around the roots. Contact with the absorbing root surfaces is the first step.

View original diagram ↗GREEN24 diagram with German labels

Rhododendron spp. · Gartenhybriden

The plant behind the product

Understand the plant and care for it with purpose.

An acidic, humus-rich root zone and dappled shade suit many garden forms. Use rainwater and monitor root-ball moisture. Fertiliser does not automatically turn alkaline garden soil into an ericaceous bed.

View the plant profile →

Add suitable growing medium

Pairs well with

Selected additions for your plant care.

Frequently asked questions

Questions before the next feed

How far do the pack sizes go?

At standard strength, 250 ml makes 125 litres, the twin pack 250 litres and 1 litre of concentrate 500 litres of prepared feed.

Does the product pH set my soil pH?

The product pH on the label describes the concentrate. It does not guarantee a particular soil pH or the pH of diluted feed. Assess compost and irrigation water separately.

When is further feeding useful?

During active growth when existing nutrition needs supplementing. Account for pre-fertilised compost and other feeds.

Which compost goes with it?

Acidic compost for ericaceous plants. Account for its initial fertiliser and review further feeding after the period stated on the bag.

Will more feed solve care problems?

Assess yellowing between green veins, brown buds and feeding damage separately. Soil pH, roots and leaf undersides give more useful clues than an extra dose of fertiliser.

Understand care problems

Plant protection advice

Assess yellowing between green veins, brown buds and feeding damage separately. Soil pH, roots and leaf undersides give more useful clues than an extra dose of fertiliser.

Plant protection products and application

General manufacturer information: these products have not been selected here as suitable treatments for the plant shown here. Before use, check the plant species, pest, application site and current instructions.

This overview does not confirm suitability for this plant or approval to mix products.

Schädlings-Frei-Organic
Schädlings-Frei-Organic

€16,95

For spraying or watering, depending on the authorised use. The method depends on the plant, pest and location.

View product in our shop →
Trauermückenfrei Organic
Trauermückenfrei Organic

€9,99

Watering treatment for fungus gnat larvae; further uses include spraying. The particular application and plant must match the instructions.

View product in our shop →
Kiron® Milben-Ex
Kiron® Milben-Ex

€12,95

Spray treatment for the mites and other pests specified in the instructions. Check the plant and location before use.

View product in our shop →

Use plant protection products safely. Always read the label and product information before use.

Safety and storage

Safety instructions

SDS – Safety data sheet available on request.

  • Do not use undiluted. Shake well before use.
  • Keep out of reach of children and animals.
  • Preferably use low-lime water or rainwater at 15–25 °C.
  • Do not apply in direct sunlight or at temperatures below 5 °C or above 30 °C.
  • Apply to a pre-moistened root zone or spray the foliage. Do not spray open flowers.

Wash your face and hands thoroughly. Use diluted fertiliser promptly and keep it out of water bodies and wastewater.

Storage

Dry · dark · above 8 °C to a maximum of 38 °C

Store in a dry, dark place above 8 °C and at no more than 38 °C.

Keep out of reach of children and animals.

Manufacturer / company placing the product on the market

GREEN24 GmbH
Am Neggenborn 125
44892 Bochum
Germany

www.green24.de

info@green24.de

Product GPSR safety information

A safety PDF is not currently available for this product. Please refer to the product information below and the label.