How To Prune Limelight Hydrangeas

Limelight hydrangeas are a cultivar with a longer blooming season than most hydrangea plants. Limelights differ from bigleaf and oakleaf hydrangeas in that they have smaller leaves and larger blossoms. The blossoms start out as a white-chartreuse and change to a lime-green throughout the bloom season. The shrub is hardy from zones 3 through 9 and grows up to 8 feet tall. Pruning should be done with an eye toward the size of blossom and shrub that you want.

Step 1

Time pruning for late fall or early spring. Limelight hydrangeas grow on new growth, and should be pruned between growing seasons.

Step 2

Determine whether you want smaller, more numerous blooms or larger, fewer blooms. The more you prune, the fewer blooms you will have. But the larger these blooms will be.

Step 3

Sharpen your pruning shears before you prune a Limelight hydrangea. This will prevent injury to the plant and help it to recover faster.

Step 4

Mix a solution of nine parts bleach and one part water. Saturate a cloth with this solution and wipe the blades of your shears with the solution between pruning Limelight hydrangeas to prevent the spread of disease.

Step 5

Remove any dead, diseased or broken stems.

Step 6

Remove 1/3 of the oldest plant stems at ground level once the plant turns 4 years old.

Step 7

Cut back the top 1/3 to 1/2 of the remaining stems just above a healthy bud. This process is called heading back.

Limelight hydrangeas (Hydrangea paniculata 'Limelight') stand out from other varieties of hydrangea with their late summer display of pointed, greenish-white flower panicles. Limelight hydrangeas only bloom on new wood, so any heavy pruning or cutting back must be done in late winter or early spring before new growth emerges, since pruning at any other time of the year will disrupt their normally abundant flower display. Rinse and dry them well before using them. Snip off a single stem at the 18 inch mark to use as a guideline for cutting back the rest of the shrub. Make the cuts angled to keep water from collecting on the wound. Water the hydrangea to a depth of 4 inches after cutting it back. Avoid early feeding since the shrub will produce weak, spindly growth.