Fertilizer and soil amendments are pretty powerful and can change the color of bigleaf or mountain hydrangea types.
If you have bigleaf hydrangeas,H.
Some common varieties are:
Organic vs. Inorganic Fertilizers: Which Is Best?
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Organic vs. inorganic fertilizer refers to using natural ingredients or introducing chemicals to the soil.
Both boost the plant’s health and encourage huge and beautiful blooms.
Phosphorus is the key ingredient that promotes bigger and more flowers.
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So the answer depends on what you prefer.
Consider a fertilizer with more phosphorus to increase the size and quantity of hydrangea blooms.
Phosphorus is the middle number, so a fertilizer labeled 10-20-10 will do.
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Liquid fertilizer is fast-release, granules can be both slower or fast-release, and spikes are timed or slow-release.
The rule of thumb is to stop applying all fertilizer after August.
A time-released fertilizer is an effective way to ensure you don’t overreach with fertilizer.
The Spruce / Letícia Almeida
serrata,or mountain hydrangea, is another species that can also change color.
Color morphing of these species depends on the soil pH.
Tochange the color of hydrangea flowers, add small amounts of sulfur or lime to the fertilizer.
The Spruce / Evgeniya Vlasova
Treat hydrangeas with sulfur, a soil acidifier, to lower the pH so flowers remain or become blue.
Certain commercial products are sold specifically to “turn hydrangeas blue.”
These products work by adding aluminum sulfate or acidifiers to the soil.
To shift their color to pink, raise the soil pH by treating bigleaf hydrangeas with lime.
While other colors of hydrangeas can be changed,white hydrangeasare not able to change color.
Hydrangeas thrive when fed a balanced or all-purpose fertilizer like 10-10-10 NPK or 12-4-8 NPK.
Fertilizers formulated for roses are another good choice.
Spring is the best time to start fertilizing hydrangeas.
Other natural fertilizer ingredients include bone meal, compost, and manure.
A Guide to Understanding Fertilizers.
General Care for Hydrangeas.
