The Candy Corn Spirea, a popular cultivar of Spiraea japonica, is a low-maintenance deciduous shrub known for its unique, multi-season foliage that shifts through shades of orange, yellow, and red. It naturally maintains a compact, mounded shape, typically reaching a height and spread of two to three feet. Proper pruning is necessary to maintain its tidy form and maximize the striking display of its colorful foliage. Understanding the correct timing and technique for pruning this summer-blooming shrub will ensure a vibrant, healthy plant year after year.
The Best Time for Structural Pruning
The most impactful pruning of the Candy Corn Spirea should be performed during its dormant period, specifically in late winter or very early spring. This timing is selected because, like all Japanese Spireas, this cultivar blooms on new wood, meaning the flowers develop on the growth produced in the current growing season. Pruning before the plant breaks dormancy prevents the removal of developing flower buds, which would happen if the shrub was pruned later in the spring.
Structural pruning involves the heaviest cuts aimed at reducing the overall size and correcting the shrub’s form. Pruning while the plant is dormant signals it to direct maximum energy toward producing new, vigorous shoots when the weather warms. This late winter or early spring window also minimizes the risk of disease transmission and avoids stimulating tender new growth that could be damaged by a late frost. All major size reductions should be completed before the new leaf buds begin to swell and open.
Essential Pruning Techniques
Structural cuts focus on removing the oldest, woodiest stems back to the ground line, which is known as a thinning cut. This technique opens the center of the shrub, allowing better light penetration and air circulation to the inner branches, which discourages fungal issues. Removing about one-third of the oldest stems each year helps maintain the plant’s youthful vigor and promotes continuous regeneration.
For general shaping, you can use hedge shears to lightly trim the entire shrub, but thinning cuts are preferred for overall shrub health. Overgrown or neglected Spireas benefit from rejuvenation pruning, which involves cutting the entire shrub back severely. This hard cut should reduce all stems to a height of approximately six to twelve inches above the soil line. While this technique sacrifices the current year’s flowers, it forces the shrub to regrow completely, resetting the plant for several years of dense, healthy growth.
Encouraging the Vibrant Foliage Color
The characteristic coloring of ‘Candy Corn’ Spirea is most intense on the newest foliage. To ensure a continuous display of this bright coloration, light pruning can be performed later in the season. This maintenance trimming should occur immediately after the shrub’s first flush of pink or purple flowers fades, typically in late spring or early summer.
Shearing off the spent flower heads, often called deadheading, stimulates the plant to produce a second flush of new growth. This secondary growth emerges with the brilliant color that defines the cultivar, extending the vibrant foliage display well into the fall months. This light, post-bloom trimming only involves removing the tips of the branches to encourage new shoot development.