Growing and caring for hydrangeas

Question: Dear Master Gardeners, I am a novice grower of hydrangeas, can you give me more information on growing and caring for them. Do I need to deadhead the old blooms? My mom says no, my neighbor says yes.

Answer: Sure, first there are two main varieties of hydrangeas. One variety flower on old growth, while the other variety flowers on new growth. If you have the old growth variety then the hydrangea will grow from the ground up and usually start blooming when they reach a certain height, approximately one to two years after planting. These are great plants but require a lot of patience. If your hydrangea is of the new growth variety it will bloom on the previous year’s growth, when new shoots grow from their root system this kicks off the flowering process. Hydrangeas come in colors of blues, reds, purples, pinks and whites. They can be kind of magical by changing colors depending on your soils acidity level.

Hydrangeas grow best in a finely mulched, well-drained soil with a slight acidic pH. If your plant is not thriving or wilting, even after adequate water, check the pH level in your soil. If needed, add lime if it’s too acidic, and add sulfur if it’s too alkaline. It is a good practice to monitor the soil of your hydrangeas to ensure that the level of pH does not fall below five or over nine, at these levels plant damage will occur.

Most hydrangeas require a minimum of six to eight hours of sunlight a day. Do not crowd the plants, allow air flow all around. Water your hydrangeas one to two inches per week during growing season. Too little water blooms will dry up and too much water, the blooms will become limp and droopy. Invest in a soaker hose if you don’t’ have one already and place at the roots directly for effectiveness. When fertilizing use a slow release type every 6 weeks from spring to fall. Do not fertilize after blooming period unless you want to encourage new growth for the next coming year, use an organic fertilizer at this stage.

Now, to answer your question on deadheading. Prune your hydrangeas in fall or early spring to remove dead blooms and stems, any crossing stems and branches that seem to be growing in odd angles. This goes for both types of hydrangea, old growth and new growth varieties. Thank you for your question. Happy Gardening!

Send questions to rheacomg@gmail.com or write to Rhea County Extension Office, c/o Master Gardeners, 125 Court Street, Suite 3, Dayton, TN, 37321.