When they're flowering, hydrangeas be one of the most beautiful and rewarding landscape plants, but they can also be one of the most frustrating when they refuse to bloom. Here are some simple but important tips to help your hydrangea perform it's best.
Hydrangeas do best in morning sun with afternoon or dappled shade. Too much sun and they'll need frequent watering, too little sun and they'll have fewer flowers. They prefer an organic, dark, loamy soil. Amend soil with a good quality compost planting mix to increase organic matter in the soil. Top dress with a 2-3 inch layer of mulch to insulate the roots an to help retain moisture in the soil. For more growth and more flowers, fertilize with a balanced fertilizer every spring.
- Any pruning of macrophylla hydrangeas should always be done by the end of July to prevent cutting off next years flower buds.
- To revitalize older plants, thin them out by cutting some of the older stems.
- To reduce the overall size, cut above a set of leaves.
The flower buds on both traditional and reblooming hydrangeasneed protection from winter and early-spring freezes. Mound straw, mulch or leaves around the base and stems. Remove this mound at the end of April.
There are very few plants that you, the gardener, can actually choose the color you want them to be in your garden. Hydrangeas happen to be one of them. With some simple amendments to your soil, you can choose between making the blooms blue or pink. And while it doesn't happen overnight, the magical blooms are well worth the wait!
The most important thing that influences the color of hydrangeas is soil pH—that's the level of soil acidity. That means you may want to start with a soil test. You can either get a soil test kit from your favorite garden center or you can send your soil to your local cooperative extension office.
In general, more acidity makes hydrangeas turn blue, less acidity (or more alkaline soil) promotes pink—that is, unless we're talking about white hydrangeas, which alas, are limited to white.
Take a look at our pH color guide to get closer to the color you prefer.
- For blue flowers, the soil needs to acidic. Aluminum Sulfate can be added to increase the acidity of the soil.
- For pink and red flowers, the soil needs to be alkaline. Lime can be added to decrease the acidity of the soil.
Okay, so how do you actually change soil pH?
To lower pH and turn hydrangeas blue, we recommend adding Espoma Soil Acidifier to the soil. It’s safe, long-lasting, and approved for organic gardening. Use 2 1/2 cups around the plant’s drip line every sixty days, until you reach the desired shade of blue.
Prefer pink? Then use Espoma Garden Lime. Sprinkle about 2½ to 5 lbs. per 100 sq. ft. in the Spring or the Fall.