Dan L wrote:
gardengal wrote:
On Nov 11, 3:41 pm, Bud wrote:
Coffee frounds are great for alkaline soil. I put a lot around my
hydrangeas. I'm getting more redish blossoms.
--
Bud

Bud, you are getting reddish blossoms on your hydrangeas because the
soil IS more alkaline. Acidic soil is what is required to produce
blue hydrangea flowers. The UCG's are not going to have much of an
impact on existing soil pH - they are only just slightly acidic
(most of the acid is extracted with the liquid coffee from the
grounds during brewing) and it would take a huge amount of them to
effect any significant change. Generally, when an acidic based
material is used as a mulch - like the coffee grounds or pine straw
- there is no change to soil pH except a slight lowering at the soil
surface.

I was wondering about that myself. Unless he wanted red blossoms.
For blue hydrangeas blue spray paint works well also
Ok, I do not that, but I do know a local gardener that does paint the
blossoms.
Looks cool from a distance.

Many years ago my wife came home with a wonderful blue and white striped
carnation that she had bought at the railway station on the way home. In
the day when carnations were $2 a dozen she had paid $1 for one stem. It
was may sad duty to tell her it was a white carnation that had been stood in
blue ink for a while and it had sucked some up through its water transport
system. But it was very pretty.

David