Mulching Hydrangeas

When growing hydrangeas, home gardeners need to know the art and practice of mulching. By following these simple steps, hydrangea bushes can not only survive fluctuating seasonal temperatures, but also thrive.

Step #1: Mulching Hydrangeas Is Important

Mulching is important for 3 reasons: it helps hold in water around the roots of the plant, decaying organic mulch addes vital nutrients to the soil and mulching helps hydranges survive winter. Make mulching hydrangeas a part of the overall garden maintenance plan.

Step #2: When to Mulch for Winter Protection

For Bigleaf and Oakleaf varieties, which bloom on buds formed from old growth wood, mulch hydrangea plants in late fall after two hard freezes. Old-fashioned hydrangeas, with their classic pom-pom shape, the Hydrangea Macrophylla, are hardy to USDA zone 5.

There are two basic mulching methods. One process involves covering the plants with mulch with shredded or chopped and dried leaves. Cover the crown and canes to a depth of 8 to 12 inches. The other way is making a mulch cage of chicken wire around the plant. Fill the cage with the mulch, again to a depth of 8 to 12 inches. The chicken wire helps to keep the mulch around the plants throughout the winter. Remove the winter protective mulch from around the plants in the spring.

Step #3: Mulching Hydrangeas in Summer

Hydranges do not like heavy soil or wet conditions, but they do like moist and well-drained soils that are enriched with organic matter. In the summer, use sphagnum peat or well-aged compost and apply to a depth of 3 inches to keep the hydrangea roots moist and cooled in the heat.

Step #4: Different Types of Mulch

Shredded wood bark or compost are good choices for mulch around hydrangeas. Pine needles are good for acid-loving plants, such as hydrangeas. Homemade compost mulch, while it takes time to decompose and be ready to use, is full of beneficial nutrients. Once ready to use, it decomposes faster than other types of mulch.

If changing color is a consideration, try the addition of pine bark mulch, which can lower the soil pH slightly. Depending on the variety of hydrangeas, generally speaking, acidic soil produces blue blooms, while more alkaline soil results in pink blooms. Bigleaf hydrangeas especially like 3 to 5 inches of an organic mulch like pine bark, pinestraw or fall leaves to both conserve moisture and control weeds.

Step #5: Repeat Process As Needed

Mulch gets blown away by wind or lawn and garden tools, so replenish and repeat the mulching process as necessary throughout the growing season. Be sure that hydrangeas are adequately protected to survive winter months with appropriate mulch covering, with or without wire cages as the variety may require. The result will be beautiful plants with plenty of showy blooms the following year.