How to Care for Hydrangeas

Expert tips, whether they’re in a vase, potted, or in the ground.

Photo by morrismedia/Getty Images

Hydrangeas are everywhere—whether they’re on your dining table, in a wedding bouquet, or the highlight of your garden, these beautiful, lush blooms are a classic. But like any other flower, hydrangeas can be a bit intimidating when it comes to growing and caring for them. We asked the experts for their best hydrangea care guidelines for any scenario—in a vase, potted, or in the ground.

In-Vase Hydrangeas

  1. Examine the Blooms
    When you’re choosing your hydrangeas at the store, look for healthy, bright green leaves with bouncy blooms. “Check for any browning spots on the petals, which would indicate sun damage,” says Callie Bladow, production director at BloomThat. “Also, due to cold storage of cut flowers, keep an eye on dark petals which could indicate the blooms have touched the side of a refrigerator. You want a flowering hydrangea that feels sturdy and not soft or spongy.” If you choose a healthy bouquet, it should last up to two weeks.
  2. Use Your Garden
    If you’re lucky to have garden hydrangeas, it’s easy to bring them indoors for a beautiful arrangement. Using a sharp floral knife or clean kitchen sheers, cut them on a bias (45-degree angle) and place them in a bowl of lukewarm water while you’re working outside. “The best time of the day to cut your hydrangea blooms is in the morning,” Bladow says. “Choose the most mature and full-looking blooms and leave the others to keep blooming. Fully-bloomed hydrangeas will look more ‘papery’ than the young-budded blooms.”
  3. Prep Them
    Hydrangeas produce a sap at the bottom of the stems that needs to be sealed off so they can soak up water. “After you cut the stem on a bias, dip the stem in alum powder, which is an onion powder that you can pick up at your local grocery store in the spice aisle,” Bladow says. “All it takes is a simple dip of the bottom of the stem and then straight into the vase.” If you don’t have alum powder, you can dip the stem in boiling water for about 10 seconds, which will produce the same effect. You’ll also want to remove the leaves from the stem, since they’ll hog all the water in the vase.
  4. Get Creative With Arranging
    You can go with a classic all-hydrangea arrangement, or experiment with mixing in different flowers or using unique vases. “I love using glass apothecary jars that have larger bases and small vase necks,” Bladow says. “The other way that we love designing with hydrangeas is to use them as grids for other flowers. There are multiple stems on the hydrangea head that keep other flowers secure, so just stick them into the flower head.” You can arrange with all types of flowers—she recommends roses, dahlias, and freesia, with some greenery like lemon leaf or variegated pittosporum.
  5. Provide Some TLC
    “Hydrangeas like cool water and it should be changed every other day with a fresh snip of the stems,” Bladow says. “You can use the boiling water trick again after you cut them to increase vase life, or add in a little flower food or simple cane sugar from your pantry in the vase.” Make sure to keep your arrangement out of direct sunlight. And if your flowers are looking sad, Bladow suggests soaking the entire hydrangea in cool water for about 45 minutes—then shake them off, cut the bottom of the stem, and place them in water with flower food. It might help revive your hydrangeas and increase their shelf life.