Water-soluble & available
All nutrients are water-soluble. In the fully diluted mixture, they are available for feeding through roots and leaves.
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- NPK concentrate with trace nutrients for hydrangeas
- For root and foliar feeding
- Product-specific dilution calculator
Feed hydrangeas. Understand their leaves and flowers.
Hydrangeas are diverse flowering woody plants. Broad leaves, woody shoots and differently shaped flowerheads define their development. Find straightforward application guidance and deeper knowledge for shrubby garden and container hydrangeas.
- Declared NPK
- 4.8 + 6.0 + 6.7With declared trace nutrients.
- Dilution
- 5 ml per 2.5 l of waterEvery 1–2 weeks during the growing season.
- Application
- Roots & foliageDilute with water before use.
- Storage
- Above 8 °C to a maximum of 38 °CStore in a dry, dark place.
Product information
Application & dosageMix and apply to suit the growth stage.
Application in one place
Measure. Mix. Apply.
Dose calculator for hydrangeas
Dilution: 5 ml per 2.5 l of water.
Your water amountRough watering-volume guide
2.5 l
Matching concentrate amount
5 ml
1 capful = 5 ml. Use a suitable measuring aid for smaller partial amounts.
Enter a water amount from 0.1 to 1,000 litres.
Only a rough guide to root watering for one hydrangea shrub. Measure height from soil level and the full leafy width. For climbing hydrangeas and continuous borders, use the actual water volume. Check moisture, medium, roots and weather; do not force the suggested amount.
How the guide is calculated
General GREEN24 guide: height (m) × width (m) × 3–4 litres. Centimetres are converted to metres. The concentrate amount follows this fertiliser’s dilution. The guide does not measure individual water requirements.
Prepare a clean container
Use a clean watering can or sprayer; preferably low-lime water or rainwater at 15–25 °C.
Calculate the amount
Enter the water volume or use the size guide for one shrub. Check root-ball moisture and drainage before watering.
Add some water first
Start by filling the container with part of the chosen water volume.
Shake & measure
Shake the bottle. 1 capful = 5 ml; use a measuring aid for smaller partial amounts.
Add the concentrate
Add the calculated amount of concentrate to the water.
Top up & mix well
Top up to the chosen water volume and mix well. Watering or spraying: see below.
When to feed? 5 ml per 2.5 l of water. Every 1–2 weeks during the growing season.
Watering · through the roots
Moisten the root ball first, then distribute the mixture evenly through the root zone. Ensure free drainage in pots and check soil moisture in borders. Do not feed dry or waterlogged roots.
Spraying · onto the leaves
Finely wet the broad leaf surfaces in the morning, evening or overcast conditions, avoiding open flowerheads. Foliar feeding belongs to the same feeding plan as root applications, not an additional flowering programme.
Characteristics & pack sizesThe concentrate and pack sizes at a glance.
Net mass: 296 g for 250 ml; 1172 g for 1 litre.
The dilution is the same for both pack sizes.
| Pack size | Price | Yield at label dilution |
|---|---|---|
| 250 ml | 9.85 € Unit price ( 39.40 €/ l) | 125.0 l |
| 500 ml – twin pack (2 × 250 ml) | 18.95 € Unit price ( 37.90 €/ l) | 250.0 l |
| 1 litre | 29.95 € Unit price ( 29.95 €/ l) | 500.0 l |
Yield at the labelled standard dilution; account for pack size and existing nutrients.
Fits your hydrangea care
For Hydrangea
For hydrangeas: mophead, lacecap, panicle and other Hydrangea species. Match position and pruning to species and cultivar.
During active growth
During active growth when additional nutrients are needed. Account for soil reserves, fresh compost and previous feeds.
Consider water and compost
Account for existing fertiliser after repotting. With our hydrangea compost, start additional feeding only after 6–8 weeks and as needed.
Beyond NPK · understand the formulation
Well mixed – available to leaves and roots
Water-soluble nutrients and coordinated formulation properties make feeding your hydrangea straightforward. Explore what the diluted mixture provides for leaves and roots.
Protected trace nutrients
Copper, iron, manganese and zinc are declared as EDTA chelates. This binding helps keep these trace nutrients available in solution.
pH buffering for the mixture
The buffer system helps regulate the pH of the finished watering or spraying solution. The source water also influences the resulting value.
Even coverage on the leaf
Good wetting and adherence help distribute the spray solution across the leaves. Dissolved nutrients are then available at the leaf surface for uptake.
Reduce hard-water effects
The formulation helps reduce adverse hard-water effects and deposits on the leaves. Low-lime water or rainwater provides a good starting point.
Feed with plant tolerance in mind
High plant compatibility when used correctly supports the development of leaves and flowering shoots. Balanced nutrition supports your hydrangea’s natural foliage quality.
Understand foliage quality and flower development
Nitrogen supports chlorophyll and protein formation, phosphorus energy transfer, and potassium water balance and substance transport. These functions work together. Leaf finish means even, well-kept foliage, not a glossy coating; flower number and colour also depend on species, pruning and position.
Chelation can reduce unwanted effects of hard water; it does not remove calcium and magnesium. The product pH of 6.4 describes the concentrate, not the soil. The pH of the diluted mixture also depends on the water used; no fixed target or soil-acidifying effect is promised.
Use clean, suitable watering or spraying equipment. Measure the water and calculated concentrate quantity carefully.
Products
Use other care products according to their own instructions. A product recommendation does not confirm tank mixing.
Do not mix undiluted concentrates. Follow each product’s own application method and dose.
Nutrient composition · NPKDeclared nutrients and their forms.
Declared nutrient percentages. Product pH: 6.4.
- 4.8% total nitrogen (N)
- 1.2% nitrate nitrogen
- 1.4% ammonium nitrogen
- 2.2% urea nitrogen
- 6% water-soluble phosphate (P₂O₅)
- 6.7% water-soluble potassium oxide (K₂O)
- 0.0075% boron (B)
- 0.003% copper (Cu) · water-soluble · EDTA chelate
- 0.015% iron (Fe) · EDTA chelate
- 0.009% manganese (Mn) · EDTA chelate
- 0.0008% molybdenum (Mo)
- 0.003% zinc (Zn) · water-soluble · EDTA chelate
GREEN24 · Plant knowledge
Broad leaves. Diverse flowerheads. A living garden space.
From fresh shoots to summer flowerheads, hydrangeas change the garden through the seasons. Mophead, lacecap and panicle forms create different effects; match position and care to your species and cultivar.
Broad foliage frames the flowers
Broad, mostly opposite leaves capture light and make sugars for growth. Leaf size and autumn colour vary between hydrangea species and cultivars.
Flowerheads with individual character
Large display florets shape many hydrangeas. Small fertile flowers are more visible in lacecap forms. A full flowerhead does not automatically mean many seeds or abundant food for insects.
New shoots, new possibilities
New shoots unfold leaves and extend the shrub. Many mopheads carry flower buds on the previous year’s wood; panicle and smooth hydrangeas flower on new wood. Identify the species before pruning.
Matching products
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GREEN24
Hydrangea Compost
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( 0.90 €/ l)
Ready to use for hydrangeas in beds and containers. Account for nutrients already included. The label specifies supplementary feeding after 6–8 weeks; consider season, growth and previous feeds.
10 litres
Delivery time: In stock · 1–3 days (DE)
Incl. VAT, plus shipping costs
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GREEN24
Kalk-Frei – Anti-Kalk concentrate for watering water
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For hard irrigation water, pretreat according to its instructions, settle for 5–6 hours and decant carefully. This is not approval for tank mixing.
250 ml · 1 litre · 5 litres
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BERGER
BERGER 5610 narrow planting trowel
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For adding growing medium and small planting jobs. Avoid damaging roots.
Delivery time: In stock · 1–3 days (DE)
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GREEN24
Garden & planting bag Pro, 140 L
10.90 €
For collecting clippings and plant debris during care and repotting.
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Incl. VAT, plus shipping costs
Growth & nutrient uptake
Leaves use light; roots take up water and mineral nutrients. The diagrams show how plant organs work together and how nutrients are absorbed.
How does a hydrangea use nutrients?
Roots · absorb and anchorFine roots explore evenly moist, aerated soil.
Active roots need water and oxygen. Humus-rich, free-draining compost and open drainage holes support the root zone in pots. More fertiliser cannot compensate for waterlogging or a dried-out root ball.
Shoots · support & connectWoody shoots form the framework for leaves and flowerheads.
Vascular tissue connects roots and above-ground parts. Potassium contributes to water balance and substance transport. Preserve healthy shoots and prune by species: do not indiscriminately remove flower buds on old wood.
Leaves · capture energyBroad leaf surfaces use light to make sugars.
Nitrogen contributes to chlorophyll and proteins; iron and manganese have roles in metabolism. Yellow leaves can still have several causes. Assess leaf age, moisture, soil reaction and roots together.
Flowers · development & diversityFlowerheads develop from buds whose formation depends on species and cultivar.
Phosphorus contributes to energy transfer but does not determine a specific flower count on its own. Showy display florets are often sterile. Pruning, bud retention, frost and water affect flowering alongside nutrition.
How nutrients enter your hydrangea
Select a point in the picture or choose a stage.
Stage 01 / 04
The solution reaches the hydrangea root ball
Apply the diluted mixture to the previously moistened root zone. Wet the root ball evenly without leaving water standing in an outer pot.
Good to knowAssess wilting through root-ball moisture and root health before increasing fertiliser.
A closer look
The first step is contact between dissolved nutrients and root regions capable of uptake. The diagram shows this function, not a species-specific tissue section. Assess wilting through root-ball moisture and root health before increasing fertiliser.
Stage 02 / 04
Uptake at the fine roots
Fine roots and root hairs contact the soil or growing medium. Dissolved nutrients enter root cells through regulated processes.
Good to knowFresh compost and existing soil reserves already contribute to your hydrangea's nutrition.
A closer look
Root hairs increase the contact area. Transport across cell membranes is distinct from water movement alone. Fresh compost and existing soil reserves already contribute to your hydrangea's nutrition.
Stage 03 / 04
Root cells regulate uptake
Cell membranes and transport proteins regulate the entry of dissolved nutrients. These processes are distinct from water moving through the plant.
Good to knowA stronger concentration cannot replace healthy roots or adequate rooting space.
A closer look
Controlled processes within living root cells lie between the surface and the conducting tissue. Functional blocks do not depict the entire root anatomy. A stronger concentration cannot replace healthy roots or adequate rooting space.
Stage 04 / 04
Onwards to shoots and hydrangea leaves
After uptake, water and nutrients can travel through the xylem into shoots and leaves. Growth and flower development still depend on species, cultivar and growing conditions.
Good to knowMophead and panicle hydrangeas do not follow the same pattern of flowering wood.
A closer look
Xylem transports water and dissolved substances. Root health and growing conditions also influence uptake and onward movement. Mophead and panicle hydrangeas do not follow the same pattern of flowering wood.
Stage 01 / 04
The solution wets the hydrangea leaves
Apply the fully diluted mixture as a fine spray to leaf surfaces. Avoid the showy flowerheads; they are not the target of foliar feeding.
Good to knowCount foliar applications within the shared feeding plan, not automatically on top of a full root application.
A closer look
The leaf surface must contact the diluted solution. Wetting is the first step, not evidence that nutrients have already been absorbed. Count foliar applications within the shared feeding plan, not automatically on top of a full root application.
Stage 02 / 04
Across the hydrangea leaf surface
The broad leaf blade has a protective surface. Dissolved nutrients can cross it; leaf age and application conditions affect how much is absorbed.
Good to knowA larger flowerhead is not a reason to increase spray concentration.
A closer look
Nutrients can cross the protective cuticle; routes through stomata may also contribute. Their contribution depends on species and conditions. A larger flowerhead is not a reason to increase spray concentration.
Stage 03 / 04
Use by living leaf cells
Nutrients that have entered the leaf can be absorbed by its cells and used in metabolism. A visible droplet alone is not evidence of uptake.
Good to knowYellowing leaves have several possible causes. Also check soil reaction, watering and roots.
A closer look
After crossing the surface, nutrients can be taken up by living leaf cells. Quantity also depends on the nutrient and surrounding conditions. Yellowing leaves have several possible causes. Also check soil reaction, watering and roots.
Stage 04 / 04
Use and possible redistribution
Movement out of the leaf depends on the nutrient and the hydrangea's condition. Foliar feeding does not promise a particular flower colour.
Good to knowBlue colour is cultivar-dependent and is influenced by soil reaction and available aluminium.
A closer look
Whether and how far nutrients move from a leaf to other parts varies among nutrients. Immediate supply to the whole plant cannot be inferred. Blue colour is cultivar-dependent and is influenced by soil reaction and available aluminium.
Development influences requirements
Distinguish establishment, growth and dormancy
Establishment & young hydrangeas
After planting, first ensure even root-ball moisture and free drainage. Fresh compost may already contain fertiliser. Base the start of feeding on root condition and existing nutrition, not plant height alone.
Leaf, shoot and flower development
Feed at the stated interval during active growth when additional nutrients are needed. Do not use a stronger concentration to compensate for missing flowers: pruning or frost may have removed flower buds on mophead hydrangeas.
Dormancy & bud protection
Pause feeding during dormancy. Autumn leaf fall is normal in deciduous hydrangeas. Species and cultivar determine winter protection; new shoots and existing flower buds can be vulnerable to late frost.
Consider species, growth stage, root condition and existing nutrients together. Height or flower count alone does not justify changing the dilution.
Application & calculator →Growing conditions & care problems
Adapt care to the growing conditions and stage of growth. If you notice changes, check light, water and roots first — then take targeted action.
How does your hydrangea grow at its site?
Pots · moisture and rooting space
Use a sufficiently large pot with free drainage. Check root-ball moisture regularly during warm weather and flowering. Keep compost evenly moist without waterlogging; do not leave water standing in an outer pot.
Borders · account for soil reserves
Humus-rich, free-draining soil and even moisture provide the foundation. Established garden hydrangeas with adequate nutrients do not automatically need extra fertiliser. A soil test can help when the nutrient supply is unclear.
Winter · roots and flower buds
Distinguish winter hardiness and bud sensitivity by species and cultivar. Protect container roots from severe freezing without blocking drainage. Watch new shoots during late frosts. Do not feed during dormancy.
Repotting & pruning · match the species
Provide appropriate root space when a pot becomes densely rooted; retain the previous root-ball level. Account for fertiliser in fresh compost. Identify the species before pruning: mophead and lacecap hydrangeas need a different approach from panicle and smooth hydrangeas.
What is changing on your hydrangea?
Aphids and mites
Inspect new shoots and leaf undersides before choosing treatment.
Mildew and leaf spots
Identify coatings or recurring spots; provide airflow and targeted watering.
Wilting or missing flowers
Check moisture and roots; late frost or incorrect pruning can also prevent flowering.
Advice for your hydrangea
These details help assess growing conditions, root problems or a possible infestation:
- Photos of the whole shrub, both sides of affected leaves, stems and any flower buds.
- Species or cultivar, garden or container, light conditions, growing medium and planting or repotting date.
- When changes began, root-ball moisture, frost history, last pruning and previous fertiliser or plant-care products.
Leaf colour alone does not prove iron deficiency. Root condition and soil reaction also affect nutrient supply. Identify coatings, webbing or recurring spots before choosing a suitable treatment.
PLANTS A–Z
Hydrangea Fertiliser in the plant guide
Explore position, root space and care for the actual plant species.
View the plant guide
PRACTICAL ADVICE
What limits plant growth
Consider light, water, root space and nutrients together. More fertiliser cannot solve every care problem.
Read the guide
Quality products
Horticultural expertise
Our own production
Made in GermanyGREEN24's own products
Quick answers before you buy (FAQ)
How much solution do the three packs make?
At the stated dilution, 250 ml of concentrate makes 125 litres of fertiliser solution, the twin pack of 2 × 250 ml makes 250 litres and the 1 litre bottle makes 500 litres. Both bottle sizes have the same declared composition and dilution.
How often should I feed my hydrangea?
The label specifies every 1–2 weeks during the growing season. Consider active growth, existing nutrients and previous feeds. Garden plants that are already well supplied do not necessarily need additional fertiliser; pause during dormancy.
Will this turn pink hydrangeas blue?
The declaration lists no added aluminium, so a particular blue colour is not a guaranteed effect of this fertiliser. For colour-changing mophead and lacecap hydrangeas, cultivar, acidic rooting conditions and available aluminium matter. White flowers cannot simply be turned blue this way.
Can I feed straight after repotting?
Fresh compost may already contain fertiliser. Plan additional feeds according to the compost label, season and plant requirements. There is no single waiting period for every growing medium.
Why is my hydrangea producing few flowers?
Check the species, previous pruning, frost damage to buds and watering first. Hard pruning can remove flower buds from many mophead hydrangeas. Extra fertiliser alone does not resolve those causes.
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.
Official advisory recommendations take precedence.
Wash your face and hands thoroughly. Use diluted fertiliser promptly and keep it out of water bodies and wastewater.
Product GPSR safety information
The original leaflet explains safe mixing and use. Follow this Hydrangea Fertiliser’s product-specific dilution in the calculator. Assess roots and existing nutrition before feeding young, newly planted or damaged plants.
Storage
Storage & product quality
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.
Keep tightly closed in the original container, separate from food and animal feed.
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.
Do not allow fertiliser residues or rinsing water to enter waterways or wastewater. Follow the disposal instructions on the packaging.
Measure concentrate accurately and apply only after dilution. More fertiliser does not compensate for insufficient light, drought or damaged roots.
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