When Should Big Leaf Hydrangeas Be Fertilized?

Bigleaf hydrangeas are known for their vibrant blooms in shades of pink, blue, and white. They are best grown in colder climates, especially after late July, to encourage consistent growth and the formation of new wood flowers later in the season. Fertilizing them monthly from early spring through late July is recommended for reblooming bigleaf hydrangeas, as it helps them maintain their health and color.

For hydrangeas planted in pots, the frequency of fertilization depends on whether they are planted in the ground or in pots. For optimal growth, apply a balanced slow-release fertilizer with a ratio of nitrogen (N), phosphorus (P), and potassium (K) that is balanced.

For hydrangeas planted in ground, fertilization should be done once a year, either in late fall after leaf drop or in early spring before bud break. A general-purpose fertilizer, such as 8-8-8 or 10-10-10, should be applied at a rate of 1 pound (2 cups) per 100 square feet in March, May, and July. Avoid fertilizing in late summer or fall.

Container plants can be fertilized in early spring and again in May. For overwintered hydrangeas, give them fertilizer in early spring and again in May. There’s no need to fertilize again during summer. For blue cultivars of bigleaf and mountain hydrangea, fertilize once in spring with a formulation for acid-loving plants.

In summary, bigleaf hydrangeas are a beautiful plant that requires regular care and fertilization to ensure their continued growth and health.