Pruning Siberian Bugloss
When and how — Brunnera macrophylla
Prune your siberian Bugloss in March and November — the optimal month is usually November.
The next pruning window is November.
When to prune?
The perennial siberian Bugloss is pruned in March and November.
With perennials, pruning is really seasonal management.
You don't prune perennials the way you prune shrubs. The work happens at three moments: (1) deadheading spent flower stems during the season to encourage repeat bloom, (2) optionally cutting back to about 10–15 cm above ground in late autumn, and (3) clearing all the old foliage in March before the new shoots emerge. Many gardeners now deliberately leave the old growth standing through winter — it protects the crown and shelters overwintering insects. Which approach to choose depends on taste and species: evergreen perennials (hellebore, bergenia) look better left alone, while wet-rotting species (hosta) need to come down after the first frost.
How to prune siberian Bugloss
Siberian bugloss requires very little pruning, which is part of its appeal as a low-maintenance perennial. The main pruning windows are March and November, but the tasks are light and straightforward. In November, after the first frosts have blackened the foliage, cut back the old leaves to ground level. This tidies the plant for winter and removes any tatty or slug-damaged foliage that can harbour pests and diseases over the dormant months. Use secateurs or garden shears and clear away the debris to keep the border clean. If your garden is particularly tidy or you prefer a neater winter appearance, this autumn cut-back is worthwhile. However, if you garden more informally, you can leave the foliage in place to provide some shelter for overwintering insects and tidy up in early spring instead. In March, before new growth emerges strongly, remove any remaining dead or damaged leaves if you didn't cut back in autumn. This is also the time to check for any winter damage and clear away old stems. If the plant has self-seeded and you don't want seedlings spreading, remove spent flower stems before seed dispersal, though many gardeners appreciate the gentle self-sowing habit. Siberian bugloss doesn't require deadheading to prolong flowering, and the blue spring blooms fade naturally without detracting from the plant's appearance. The real ornamental value lies in the bold, heart-shaped leaves that remain attractive all season. Focus your efforts on removing tired foliage rather than fussing with flowers, and your brunnera will reward you with healthy, lush growth year after year.
Common mistakes
✗ Cutting back too early in spring
Late frost can still strike and the old foliage protects the crown. Wait until the first new shoots are visible (usually mid-March) — then you know the season has actually started.
✗ Skipping deadheading
Hardy geranium, salvia, lupin and delphinium will give a second flush if you cut spent stems back to just above a pair of healthy leaves as soon as the first flowers fade.
✗ Cutting ornamental grasses down in autumn
The dry stems are the whole point of winter interest, AND they protect the crown from frost and waterlogging. Cut down to a fist's height only in late February.
Combine with feeding
In March you can combine pruning with feeding — efficient, and you only disturb the plant once. Read the full care guide for siberian Bugloss →
Hold off on pruning
Better to wait than prune at the wrong moment. The next optimal window is November. Until then: leave the plant alone — only remove dead or diseased wood (which you can do year-round).
