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Annuals/Hydrangeas - color


I have Hydrangeas in my garden which are normally pink but this year one or two are growing some blue flowers. Why?. Can you please tell me how to make others turn blue?
Thanks Jack

Your soil is turning acid.  That's a natural trend, caused by metabolism of good soil bacteria.  Note it is a slow trend -- it does not happen overnight, although ads for fertilizers and general advice seems to give people the impression that last week's pink flowers will turn blue if you just change the pH of the soil or add Miracid. Nope.

If you prefer the blue, get started now.  Don't go crazy.  Blue flowers come to those who wait.

Acidify the soil with top dressings of peat moss, humus, aged compost and coffee grounds.  Avoid alkaline exposure -- wood ashes, grass-pleasing lime you may have added to your lawn -- and don't expect overnight results.  A watched pot never boils.

If you can't stand it, run out and get a simple soil testing kit to use weekly.  This is like losing weight.  We don't go on a diet and lose 10 lbs a week without surgery.  Think of it the same way.  Test once a month in the growing season and write it down so you can see progress.  Pouring vinegar in the soil and then testing the pH is like taking off your shoes and weighing yourself to see how many pounds you've lost.  Remember: Slow and steady wins the race.


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Decisions, decisions... If you can't make up your mind which Annuals to grow, you're not alone. Problem with your new flowering Annuals flats? I`ve been there, done that. Petunias, Sweet Alyssum, Larkspur, Marine Blue Lobelia -- they all grow here at my house on Garden Street on Long Island, N.Y.. Cutting and Cottage Gardens, Sun and Shade Gardens, White Gardens and Night Gardens, I`ve done them all. Annuals are the perfect summer flower, bursting with color June through fall's first frost. I can`t speak on Cactus or tender Tropical Plants -- they don`t grow outside in my Zone 7. I`m no Farmer, so I cannot guide you on Fruits and Vegetables. But whether it`s an Annual you want to start from seed, mail-order or pick up at your local garden center, I can help you grow amazing blooms this Summer. Yes, together, we can turn your neighbors green with envy.


I have a lifetime of gardening behind me here on the North Shore of Long Island. While I have degrees in related fields, there's nothing like hands-on work to build real knowledge. I stay on top of current science -- there's a boom in research, and Kingdom Plantae is filled with surprises. By the way, I really do live on Garden Street.

Gannett newspapers, The New York Times, and hundreds of others - but not on Annuals.

B.A., botany; graduate credits in European Intellectual History and Political Science; minor coursework in related fields, docent training at our local botanical gardens (required for volunteers). I'm currently working on an advanced biochemistry degree.

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