How can you change the colour of hydrangeas from white to pink or blue?

I went to this site and it has tons of stuff about hydrageas! Check it out, it also has a lot of pictures. So, here's the copy/pasted info!:



Flower color in H. macrophylla is dependent on cultivar and aluminum availability. Aluminum is necessary to produce the blue pigment for which bigleaf hydrangea is noted. Most garden soils have adequate aluminum, but the aluminum will not be available to the plant if the soil pH is high. For most bigleaf hydrangea cultivars, blue flowers will be produced in acidic soil (pH 5.5 and lower), whereas neutral to alkaline soils (pH 6.5 and higher) will usually produce pink flowers. Between pH 5.5 and pH 6.5, the flowers will be purple (see image at left) or a mixture of blue and pink flowers will be found on the same plant.

There are a few cultivars that never produce blue flowers. In low pH soils, flowers of these "non-bluing" cultivars turn a dull reddish-purple. In higher pH soils, the flowers of these cultivars are a vivid deep pink color. Some non-bluing cultivars are 'Alpengluhen'

To change the color of a hydrangea planted in the garden, it is necessary to change the soil pH. To raise the pH, add lime. One way of lowering the pH of the soil is to add aluminum sulfate. Additions of acidic organic matter (peat, pine bark) can also help lower soil pH. Exact amounts of lime or aluminum sulfate necessary to get the desired flower color will vary depending on current soil pH and soil type.
How can you change the colour of hydrangeas from white to pink or blue?
Buy pink or blue.
Reply:You probably need to acidify your soil. You might want to inquire at your local nursery or County Extension Office about doing an inexpensive basic soil test. However, hydrangeas and a few other plants need a more acid soil, than say vegetables, to do well. The color of the flowers (on hydrangeas) have a direct correlation to the soil acidity.
Reply:Spray Paint, joking



White is the way it is. Blue or Pink is strictly the PH of the soil, change the PH and you change the color
Reply:If you want them white, do nothing. If you want them pink, cross breed with a pink peony. Blue, put old horseshoes or railroad nails, anything rusty in the ground around the plant. These are the "cheap" not cost remedy's I use. No $ for nurseries with gas at $4.00!! They work!
Reply:white does not change colors except to fade to a pinkish red as the flower ages..... sometimes to greenish yellow..... only blue and pink will change colors and the aluminum sulfate info is correct... along with the acidic soil for blue and alkaline soil for pink.... pink is easier if the plant is potted....



see 'color change' here... on the left side column...



http://www.hydrangeashydrangeas.com/
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