Hydrangea Magic: Changing Bloom Colors
by Amanda
Hydrangeas: Color-changing Magic?
A common question we get from gardeners each year is: "Why are my blue Hydrangeas pink, or, Why are my pink Hydrangeas blue?" The answer is really quite simple (and no, it's not magic). The color of your Hydrangea blooms are directly linked to the PH levels of your soil.
Knowing this important information means you can easily (well, somewhat easily) change the color of your Hydrangea blooms! Alkaline soil produces pink blooms and acidic soil produces blue blooms. The first step in determining the PH of your soil is to do a soil PH test to determine the acidity of your soil.
Blue to Pink:
A test result below 7 means that your soil is acidic (blue blooms). To raise the PH of your soil (to turn blooms pink), try adding limestone – most packages will tell you how much to add to increase your PH to the correct levels.You can also try using a fertilizer with high levels of phosphorus in it. This helps keep the aluminum in your soil from entering the root system of your plant. If you can't seem to lower the acidity in your garden beds, consider planting in pots.
Pink to Blue:
A test result above 7 means that your soil is alkaline (pink blooms). To lower the pH of your soil (to turn blooms blue), you can add things such as sulfur, compost, pine needles, or pine bark. This will help to add some acidity to your soil. You can also try an organic fertilizer that is low in Phosphorus and high in Potassium.
![Snowball Hydrangea Annabelle, Hydrangea arborescens Annabelle]()
Annabelle‚ Hydrangea is famous for its huge, snow-white blooms and excellent cold hardiness. This shorter variety grows 3 - 5 ft tall and flowers reliably, even after severe wi...
Learn MoreAnnabelle Snowball Hydrangea Snowball Hydrangea Annabelle Hydrangea arborescens Annabelle$18.65Per Plant - 4" PotAnnabelle' Hydrangea is famous for its huge, snow-white blooms and excellent cold hardiness. This shorter variety grows 3 - 5 ft tall and flowers reliably, even after severe winters and intentional pruning. Its enormous 10" blooms and ability to adapt to both cold and heat have made 'Annabelle' one of the most popular hydrangeas in the country. (Hydrangea arborescens)![Ruby Slippers Hydrangea with close up of white-pink petals, Oak Leaf Hydrangea Ruby Slippers, photo by Dave Whitinger, National Gardening Association]()
‚Ruby Slippers‚ Oakleaf Hydrangea delivers oversized, cone-shaped blooms that arrive in white to light pink and deepen to a reddish-magenta as they age. A compact shrub, ...
Learn MoreRuby Slippers Oakleaf Hydrangea Oakleaf Hydrangea Ruby Slippers Hydrangea quercifolia Ruby Slippers$23.99Per Plant - 4" Pot'Ruby Slippers' Oakleaf Hydrangea delivers oversized, cone-shaped blooms that arrive in white to light pink and deepen to a reddish-magenta as they age. A compact shrub, 'Ruby Slippers' is a fine choice for small spaces and planting in containers, or training into a low hedge. Its lobed, oak-like leaves change to burgundy as fall appoaches, bringing another layer of vibrant color to the landscape. (Hydrangea quercifolia)![Mophead Hydrangea All Summer Beauty, Hydrangea macrophylla All Summer Beauty]()
‚All Summer Beauty‚ Hydrangea is a compact, long-blooming mophead variety that produces big, bouncy flowers on 4 ft shrubs. Because it blooms on both new growth and old w...
Learn MoreAll Summer Beauty Mophead Hydrangea Mophead Hydrangea All Summer Beauty Hydrangea macrophylla All Summer Beauty$18.65Per Plant - 4" Pot'All Summer Beauty' Hydrangea is a compact, long-blooming mophead variety that produces big, bouncy flowers on 4 ft shrubs. Because it blooms on both new growth and old wood, flowers will form throughout the season, even after a harsh winter - which can be the undoing of other hydrangeas. Known for its bright blue blooms in acid soils, expect to see shades of pink and purple where the ground is more alkaline. (Hydrangea macrophylla)![White Climbine Hydrangea Vine, Hydrangea anomala petiolaris]()
Climbing Hydrangea Vine pairs the blooms of white lacecap hydrangeas with the vertical coverage of a foliage-rich vine. Unlike other climbers, this flowering vine also produces horiz...
Learn MoreClimbing Hydrangea Vine Climbing Hydrangea Vine Hydrangea anomala petiolaris$17.32Per Plant - 3" PotClimbing Hydrangea Vine pairs the blooms of white lacecap hydrangeas with the vertical coverage of a foliage-rich vine. Unlike other climbers, this flowering vine also produces horizontal branches that showcase even more blooms and a thicker cover of glossy green leaves. Cinnamon-red bark is shaggy and textured, providing winter interest. A bit slow to start, but expect a growth spurt once established. (Hydrangea Anomala Petiolaris)
The best success rate comes from gardeners who grow their Hydrangeas in containers, which allows for them to completely control the acidity of the soil with no outside factors.
Also note that it is easier to change a pink Hydrangea to blue than blue to pink. Other colors of Hydrangea cannot change colors with soil acidity.
What experience do you have changing the colors of your Hydrangeas? Please post in the comments below or on our Facebook Page.
Happy Gardening!
