Growing Home Ep. 13- Don't Be a "Strangea" to Hydrangeas

Why don't my hydrangeas bloom?
Having hydrangeas in your garden can remind you of vacations gone by, even in the middle of the workweek. Join Terry and Len as they talk about the different varieties of this plant, and caring for them through the year, so you too can enjoy these impressive flowers.

Macrophylla Hydrangea

Most kinds of hydrangea are easy to grow, but the macrophylla hydrangea are particularly hard to grow.

The flowers of the Macrophylla hydrangea can be shaped as ‘mopheads’ (which look ball-like) or ‘lace caps’ (which have a ring of flowers surrounding smaller flowers).

Macrophylla hydrangea prefer warmer climates. Here in CT, that means along the shore and the Connecticut River.  The climate is similar to the plant’s home of coastal Japan.

The color of its flowers can depend on the soil ph. Bellow 7, you get blue hydrangeas; above 7, you get pink hydrangeas. As a result, the color of the plant may change if the plant was grown in a different part of the country than where its planted.

Some of the newer macrophylla varieties are reblooming, meaning they’ll bloom at least twice in their season. The re-blooming behavior is achieved in plants that are bred to have shorter internodes, which is the stem growth between blooms. The shorter the internode, the shorter production cycle for the plants next set of blooms.

Serrated Leaf Hydrangea

Serrated leaf hydrangea originates from mountainous areas of Japan. These plants are hardier, so they can stand up to the temperatures of northern Connecticut. These plants are also smaller and have lace cap flowers.

Smooth Leaf Hydrangea

The smooth leaf hydrangea originates from the US. Also known as the Annabelle, its name comes from being found in Anna, Illinois.  It has a mophead flower and is known for attracting pollinators. These plants can have difficulty supporting their large flowers after a rain, but have been bred to strengthen their stems. They are also late bloomers from mid-summer to late fall.

Hydrangea Paniculata

Hydrangea Paniculata are later bloomers with cone shaped flowers. These flowers bloom very late, between August and October. These hydrangeas are hardy and tree-like. They can be pruned in late fall or early spring. Paniculata can grow 2 or 3 feet in a season, so be fine with cutting it back aggressively. Len recommends this plant as a beginner’s hydrangea.

Oak Leaf Hydrangea

 Oak Leaf Hydrangeas are Len’s favorite. A native plant, they have a “graceful” conical flower and the flowers grow at the end of the branch, so you can easily see all the flowers. The flower starts as a white pink, and eventually turns purple. The leaves also turn colors from a green to a deep red.

Climbing Hydrangea

Climbing hydrangeas can grow on arbors and up brick walls. The climbing hydrangeas have lace-capped flowers. They take time to get established and need a substantial structure for their heavy vines. The climbing hydrangea will start growing significantly after 3 years, then you need to start training the flower. Use a pergola, or a metal arbor to hold it.

Planting the Hydrangea

Hydrangeas like to have access to morning sun and shade.

Dig a hole twice as wide as the container for the plant.

Score the roots before planting and put it in the soil as deep it was in the pot.

Only water manually for the first year. Fertilize only after the plant is established, or if it’s absolutely necessary.

Regular fertilizing can make a plant too big in a matter of years, and can also make a plant “floppy.”

Hydrangeas need good drainage. Terry added peat moss and compost to his soil to help with drainage.

Caring for Hydrangeas

Keep the hydrangeas as warm as possible in the winter. Temperatures below 0 degrees Fahrenheit can kill the budding of Macrophylla hydrangeas that will flower in season.

You can wrap the hydrangea in burlap to protect it. Have a generous amount of material ready, and wrap the whole plant two or three times. Save the burlap so you can use it for years to come.

Pruning Hydrangeas

Prune back the new growth Hydrangeas (Paniculata, Smooth leaf) aggressively, as they can get out of hand. Use hand shears/loppers to keep them trim. Marcophylla hydrangeas should be pruned immediately after flowers pass bloom in the current season.