How to Cut Hydrangeas in Your Garden So They Last Longer in Floral Arrangements

Growing hydrangeas in your garden isn't just a way to enhance your home's curb appeal—the perennial flower looks great inside your house, too. Whether you display the cut blooms on their own in a vase or use them as a textural component in flower arrangements, the beloved florals will add a pop of color to any room.

Despite their beauty, hydrangeas can wilt quickly if they're cut incorrectly. Luckily, there are some things you can do to make these flowers last longer—and it all starts with knowing how and when to snip them from your garden. 

When to Cut Hydrangeas

Cutting your hydrangeas at the right time is key. "First and foremost, flower heads are not ready for harvesting until mid-summer," says AIFD floral designer Jane Godshalk, an instructor at Longwood Gardens. "Check to make sure your flower head is open and the color is developed." Avoid cutting during the hottest part of the day; harvesting in the morning or evening is ideal. 

How to Cut Hydrangeas 

Regardless of the type of hydrangeas you're growing—and whether it blooms on old or new wood—the cutting process is the same. Start by using clean, sharp shears, then make your cut. "Cut stems above a node, and include at least two leaf groups on the cut stem," says Godshalk. 

How to Make Cut Hydrangeas Last Longer

After cutting your blooms, there are a few tips to follow when using hydrangeas in your flower arrangements. 

Recut the Stems

After the initial cut in the garden, your hydrangea stems will need one more trim. "Once indoors, recut the stem above a leaf node at a sharp angle and split the stem up the middle about 1 to 2 inches to allow for maximum hydration," says Godshalk.  

Dip Stems in Alum Powder

Dipping the cut stems into a 1/2 inch of potassium aluminum sulfate, or alum powder—a pickling ingredient often available at the grocery store—can increase the stem's ability to absorb water. 

Remove Excess Leaves

Cut off any foliage that sits below the water line. "If you don't need the leaves above the water line either, removing those will help the stem push all water to the blooms instead of diverting to the leaves," says Rachel Bridgwood, co-owner of Sweet Root Village.

Put Them in Water Quickly 

Don't cut your hydrangeas and then leave them to sit around before making making your arrangement. "Place your stems immediately in water after cutting to promote healthy absorption of water versus giving them time to intake too much air," says Bridgwood. "The stems also release a sap to help the plant seal off any loss of moisture, but this sap will also inhibit new intake of water—so getting that stem directly into water as fast as possible will mean less sap being released by the plant."

Refresh Water Regularly 

Every two days, refresh the water in your vase to keep the buildup of bacteria to a minimum. "Hydrangeas like to be in fresh water," says Godshalk. If you need to support your flowers in situ, use chicken wire instead of floral foam, which will help keep the stems submerged in water.