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Advice

DCM ALUIN for deep blue hydrangeas

The colour of hydrangeas depends on the acidity level of the soil and the amount of free aluminium and iron. For a deep blue colour, sufficient iron and aluminium ions are needed as well as an acidic soil. This is why the application of DCM ALUIN is recommended.

DCM ALUIN (ALUM), aluminium in the form of potassium alum, is a product specially designed to turn hydrangeas blue. By applying DCM ALUIN (ALUM), your flowers will quickly turn blue and maintain this blue colour.

Instructions for use

For optimal results, apply DCM ALUIN (ALUM) in spring (just before flowering) and in autumn. When planting a hydrangea in spring, the full dose (fall and spring) can be applied at once. Weigh the correct amount of alum and dissolve it in lukewarm water (10 g in at least 100 ml of water). Stir well to break up any clumps. Pour around the plant, without touching the leaves. For better distribution, you can also dissolve the alum in a larger amount of water.

DCM ALUIN (ALUM) thumbnail
DCM ALUIN (ALUM)

To turn hydrangeas blue

Dosage:

In open field - single hydrangeas

  • diameter 50 cm: 2 – 3 g/plantt

  • diameter 100 cm: 8 – 12 g/plant

  • diameter 200 cm: 32 – 48 g/plant

In flower beds

10 - 15 g/m2

In pots

5 – 10 g/L potting soil

You will find a measuring spoon in each bucket: 1 level spoonful weighs 10 grams!

Extra tips for hydrangeas

Keep in mind that some pink varieties will turn lilac at best after applying DCM ALUIN (ALUM) and that white hydrangeas, such as Annabelle, will maintain their white colour. When planting hydrangeas, acidify and improve the soil with DCM VIVIMUS® FOR HEATHER/RHODO (soil improver for heather, rhododendrons and all acid-loving plants). Use DCM MESTSTOF RHODO, HORTENSIA & AZALEA (FERTILISER RHODO, HYDRANGEA & AZALEA) to fertilize your hydrangeas. This fertilizer is adapted to the needs of acid-loving plants. It is rich in potassium and magnesium for abundant flowering and shiny green leaves.