(no subject)

[mamculuna]

Garden question: Have any of you ever tried getting pink hydrangeas to turn blue? I know you do it by adding aluminum sulfate to the soil, but I'm wondering how hard that is to manage. Does it hurt other plants near them?

Most hydrangeas I see around here are blue and we have very acid soil, generally, so maybe it will happen naturally in the next few years, but I planted one I thought was going to be blue and the blossoms are beginning to open and turn pink. Hmm, I'm just realizing that they're planted next to the room we added on a few years ago, and the builder dumped a lot of cement water around there. May not be so acidic right there, after all.

Purple wouldn't be bad, either...but blue is what I really want.

Comments

[oursin.livejournal.com]

My own understanding is that people used to bury rusty nails underneath the hydrangeas and that turned them blue, but this may be complete urban myth.

[londonkds.livejournal.com]

Not necessarily. Rust is iron (III) oxide and that's quite acidic when it hits water.

[ann1962]

When we lived in CT where hydrangeas grew very easily, people would just buy aluminum sulfate in some form (I am not sure) and add it. People talked about manipulating the colour fairly easily, so I bet you can have success.

[mamculuna.livejournal.com]

Can't hurt, if I can find some. Just threw some away, unfortunately.

[mamculuna.livejournal.com]

That's what I've heard, too, and will try. I have pine straw mulch so the soil should get more acid pretty quickly.