I have written about Limelight (Paniculata) hydrangeas before, but because I continue to receive questions concerning them, I have decided to write about them again. If you grow, or plan to grow, this lovely flowering shrub, this column may be useful to you.
We have seven lovely Limelight hydrangeas in our landscape. The majority are planted on the right side of our driveway, down the hill. One large shrub is planted on the left side, near the bottom of the hill. Right now, all of the shrubs are in full bloom and are quite lovely.
The soil in these planting beds drains well, which these plants love. In addition, they flourish in lots of sun. The hydrangeas on the right side of the driveway are planted near a large sweet gum tree that provides some shade for the shrubs. The Limelight hydrangea on the left is stationed in full sun and is thriving, although most gardening experts recommend some afternoon shade.
If allowed, these plants will grow up to 10 feet tall and equally as wide, producing, large cone-shaped panicles that point straight up. The panicles start out as creamy white blossoms, maturing into a shade of lime green. In the fall, as the panicles begin to fade, they take on a reddish hue.
A question I have often received about Limelight hydrangeas is how and when to prune them. They bloom on new growth; therefore, they should be pruned in late winter, before any new growth appears. When Limelight hydrangeas are planted as a foundation plant, they work better as a smaller shrub and should be pruned each year. Out in the landscape, where space is unlimited, the shrubs may be allowed to grow as tall and full as possible. Our Limelight hydrangeas are planted where they can grow large, in limitless space; therefore, the only pruning they receive each year is to remove the old blossoms. There have been years when I did no pruning at all and, even then, the plants displayed abundant blossoms.
The Limelight hydrangea flowers in the summer; therefore, in early spring, when the flowers are forming, apply a handful of fast-release fertilizer. Reapply the fertilizer in May and July. Be sure to spread the fertilizer on the ground under the drip line of the branches and not just the base. Work into the soil surface and apply water.
Carol (Bonnie) Link is an Etowah County Master Gardener and an experienced garden writer. Her weekly column is designed to help and encourage others in their gardening endeavors. Send questions or comments to firstname.lastname@example.org.