Eliminate weak or spindly shoots.

Sep 21, Prune your"Diablo" ninebark shrub in the early to mid-spring after the last hard frost has passed but before new shoots Follow the natural form of the shrub, and place cuts 1/4-inch above a leaf node to encourage regrowth and branching. How do I prune Diablo ninebark? Cut back long, leggy twigs that stick out from the top, sides and bottom of the ninebark. Use pruning shears to cut twigs 1/4 inch above an exterior bud, or a bud facing the outside of the shrub.

Ninebark – Pruning, Winter Care and Fertilizing. This shrub is often used in mass plantings or as a hedge. The same pruning technique can be used if they are planted as a specimen.

If you cut a branch on 1 side of the shrub, make sure that the opposite side has a similar angle to it.

For these plants, pruning should be done in the early spring, before they leaf out. Shear or prune the outer branch tips to shape and reduce the size of the plant.

How to prune: If you just need to shape your ninebark a bit, you can give it a light shearing during the active growing season, after it flowers. This can be done with bypass pruners or with power shears. Just be aware that this can reduce the amount of potential showy fruit you will see in summer and treegrind.barted Reading Time: 2 mins. Jan 29, I have considered pruning Ninebark ‘Diablo’ back hard to within a foot of the ground to get nice fresh and vivid foliage this spring.

Of course, that would mean sacrificing any blooms and subsequent red seedheads.