Fertilizing hydrangeas – the best hydrangea fertilizers

The manufacturers offer hobby gardeners special hydrangea fertilizers that are precisely tailored to the requirements of the ornamental shrubs. It is not always clear from the product name at first glance that the fertilizer is suitable for hydrangeas. Experienced hobby gardeners know that rhododendron and azalea fertilizers can also be administered to hydrangeas without hesitation, as these types of plants differ minimally in terms of soil quality and nutrient supply.

Complete fertilizer

Substral Osmocot rhododendron and hydrangea fertilizer

With this resin-coated depot fertilizer in a stand-up pouch, Substral is breaking new ground. One application per season is enough to provide the hydrangeas with all the nutrients for over 6 months. Each of the fertilizer beads is surrounded by a layer of resin that ensures that the fertilizer is gradually released to the plants.

• Dosage: 60 g to 80 g per plant.
• Price for 750 g: from 10 euros.

Compo Rhododendron slow release fertilizer

The classic NPK fertilizer is equipped with extra nitrogen and reduced amount of phosphorus. The partially coated granulate works for a period of 3 months before it is possibly re-fertilized. 2% magnesium and iron have a beneficial effect on the development of leaf green.

• Dosage: 20 g to 120 g per m².
• Price for 1 kg: from 8 euros.

Beckmann rhododendron fertilizer

Organic-mineral agent for azaleas, heather and hydrangeas alike. Ensures a balanced supply of nutrients, promotes microorganisms and humus formation. One dose of the fertilizer lasts for up to 3 months.

• Dosage: 80 g to 120 g per m².
• Price for 4 kg: from 13 euros.

KEYZERS Rhododendron fertilizer for all bog plants

A high-quality product that enjoys consistently good reviews from users. The mineral-organic fertilizer with an NPK composition of 8 + 5 + 3, however, has its price compared to competitive products.

• Dosage: a handful of fertilizer per hydrangea in spring and summer.
• Price for 1 kg: from 19.90 euros.

Special fertilizers with a blue color

Mother nature doesn’t know blue hydrangeas. A hobby gardener can, however, color his white or pink hydrangea plants blue by influencing the composition of the soil. In acidic soil with a pH value of 4.0 to 4.5 and a sufficient content of aluminum, the transformation of the ornamental shrub begins and is completed after 1 to 2 years. The following fertilizer preparations contain a blue maker as an addition.

Cuxin hydrangea fertilizer with blue maker

The organic-mineral NPK fertilizer allows a dust-free, selected even distribution of the granulate. At the same time, the preparation contains 500 grams of alum for 1 kg of fertilizer to set the desired blue coloration of the flowers in motion and to stabilize them.

• Dosage: 150 g fertilizer in March / April per m² plus 15 g alum in autumn and just before flowering.
• Price for 1.5 kg: from 9 euros.

Norax hydrangea fertilizer ‘gardener quality’ with deep blue dye

With NPK in the composition 8 + 6 + 8 plus alum, this organic-mineral fertilizer is equipped with everything that is relevant for a splendid bloom. Thanks to the organic components, such as horn shavings, the agent also makes a valuable contribution to improving the soil.

• Dosage: 50 g to 100 g per plant once in spring.
• Price for 0.9 kg: from 8 euros.

Garden paradise hydrangea fertilizer plus hydrangea blue

With 6% nitrogen, 5% phosphorus and 10% potassium, this fertilizer focuses specifically on the bright flower color. As a blue dye, alum is contained in an extra bag so that hobby gardeners can selectively dye selected hydrangeas.

• Dosage: approx. 70 g fertilizer per plant.
• Price for 0.9 kg: from 8 euros.

Liquid fertilizer

Chrystal Azalene and Hydrangea Fertilizer

This NPK fertilizer with 6% nitrogen, 4% phosphorus and 7% potassium is also equipped with the Vitamin Plus system. Trace nutrients such as boron, iron, copper or magnesium are used to promote health in connection with a splendid bloom.

• Dosage: 1 cap for 1 liter of water.
• Price for 500 ml: from 5.50 euros.

Euflor Vital Hydrangea Blue Fertilizer

This agent scores with an additional brown algae extract to stimulate the resistance and growth of hydrangeas. Since the NPK fertilizer solution is well measured with 8 + 3 + 4 and 0.1% iron, the preparation fits seamlessly into the well-known branded products. The term ‘blue fertilizer’ is somewhat misleading, because it does not contain an extra portion of alum for the blue color of the flowers.

• Dosage: 1/2 cap to 2 liters of water.
• Price for 250 ml: from 5.30 euros.

Cuxin Rhododendron & Hydrangea Liquid Fertilizer

Mineral raw materials ensure a quick start effect, while organic ingredients are responsible for the long-term effect.

• Dosage of the concentrate: weekly 3-5 ml to 1 liter of irrigation water
• Price for 800 ml: from 7.10 euros.

Liquid fertilizer with Blaumacher

Manna Lin H blue hydrangea fertilizer

The practical solution for hydrangeas in the tub, which should turn blue or should keep their bright blue tone. For this purpose, an appropriate dose of alum was added to the NPK fertilizer.

• Dosage: 1 cap for 10 liters of water
• Price for 500 ml: from 6 euros.

frux ClassicLine hydrangea fertilizer blue

The special fertilizer for bargain hunters, which with an NPK content of 8 + 3 + 4 and aluminum contains everything that healthy hydrangeas could wish for. Hobby gardeners who do not attach particular importance to the long-term effect of the fertilizer are best advised with this product at a good price / performance ratio.

• Dosage: every 2 weeks 1 cap for 3 liters of irrigation water
• Price for 1 l: from 5.95 euros

terrasan hydrangea fertilizer blue liquid

The traditional manufacturer of specialty fertilizers attaches great importance to convincing customers with the best quality at an affordable price, instead of costly advertising. Experienced hobby gardeners are familiar with the hydrangea fertilizer with the NPK dosage 7 + 3 + 5.

• Dosage: every 1 to 2 weeks 1 cap for 3 liters of water.
• Price for 1 l: from 5.29 euros.

Organic fertilizer

A growing number of hobby gardeners strive for an exemplary ecological balance in their own green realm. This includes not only natural planting with bee pastures and bird protection trees, but also the consistent use of purely organic fertilizers. Since the relatively high nitrogen requirement must be taken into account in the context of the nutrient supply to hydrangeas, the following biological agents are particularly suitable.

Deciduous compost

As compost, oak leaves make an excellent natural fertilizer for hydrangeas because they have a strong acidic effect. True, it takes up to 2 years to complete the rotten; Of course, from this point on, the leaf compost saves any mineral fertilizer. There is nothing wrong with adding other leaves, such as the foliage of birch or alder, as long as the flowers are not turned blue. The addition of lime to accelerate composting should be avoided.

• Dosage: Work in a 2 cm layer of compost every 14 days from March to the end of August.
• Cost: none

Needle compost

In its influence on hydrangeas, similar to foliage, the production of coniferous compost can take up to 3 years. Spruce and larch needles rot a little faster than the thicker pine needles. Experienced hobby gardeners layer the needles alternately with lawn clippings and garden soil.

• Dosage: Spread around the hydrangeas every 2 to 4 weeks in spring and summer.
• Cost: none

Hornspäne / Hornmehl

Horn shavings are the crushed hooves and horns of cattle for slaughter. Processed into fine horn meal, the effectiveness is accelerated. The nitrogen-rich material is very popular as an organic fertilizer because it is active throughout the season after a single dose in the spring.

• Dosage: In spring, work a handful of each hydrangea flat into the soil.
• Costs per kg: from 1.80 euros.

Neudorf Azet hydrangea fertilizer

A purely organic fertilizer, consisting of vegetable and animal ingredients as well as microorganisms. An advantageous solution for biologically oriented hobby gardeners who do not have the option of composting themselves.

• Dosage: Spread 40 g to 75 g per m² in March and July.
• Price for 2 kg: from 8 euros.

Coffee grounds

Thanks to the high nitrogen content, this home remedy is ideal as a hydrangea fertilizer, especially since it also contains some phosphorus, potassium and magnesium. Since, at the same time, coffee grounds have a reducing effect on the pH value of the soil, loosen up the soil and even drive away the snails, environmentally conscious gardening enthusiasts no longer want to do without the product.

• Dosage: Sprinkle a thin layer of coffee grounds over and over again as it grows.
• Cost: none

COMPO natural fertilizer for rhododendrons with guano

This organic fertilizer for hydrangeas and other bog plants contains 100% natural components, including guano, one of the best natural fertilizers around. In addition to the supply of nutrients, the preparation activates soil life and humus formation.

• Dosage: 40 g to 90 g per m² every 4 weeks from March to August / September.
• Price for 1 kg: from 6 euros.

Conclusion
Since hydrangeas have different requirements in terms of nutrient supply and soil quality than the vast majority of ornamental plants in the garden, specialist retailers offer separate fertilizers. Here the focus is on a higher nitrogen content in unison with the reduction of the pH value below 5. The best hydrangea fertilizers go one step further in the direction of specialization. These preparations contain aluminum or alum as an additive so that they act on white or pink flowers in such a way that they turn blue over time. Of course, the environmentally conscious hobby gardener is not dependent on the use of mineral or organic-mineral products. With deciduous or coniferous compost, coffee grounds and horn shavings, he has the best hydrangea fertilizers that mother nature has to offer,