Photo: USDA-NRCS PLANTS Database / Herman, D.E. et al. 1996. North Dakota tree handbook. USDA NRCS ND State, Public domain · source
Pruning guide · Conifer
Colorado blue spruce: when and how to prune
Picea pungens
Colorado blue spruce is best pruned in May–June.
| Pruning months | May–June |
|---|---|
| Nesting season (15 March–15 August) | Take care in May–June |
| Good for bees, butterflies and birds | Yes, for birds |
| Native to Belgium | No, planted |
Colorado blue spruce: when to prune it?
Dead, diseased and broken branches can be removed at any time of year. To keep it compact, shorten the new shoots in May–June.
Colorado blue spruce: how to prune it?
- Never cut back into bare branches: a spruce won’t regrow there.
- A spruce that has lost its top will grow a new one if you tie a side branch upright.
How much to cut, and how often?
- One pruning period a year: May–June.
- Grows best when left alone. Only remove dead, diseased or awkward branches.
- Most conifers do not regrow from old, bare wood. So never cut back into the brown part (exception: yew).
What does it mean for wildlife?
- Pruning in May–June can fall in the nesting season (15 March–15 August). Check carefully for nesting birds first: disturbing an active nest is against the law.
- Prunings can go on a dead hedge or brash pile in a corner of the garden: shelter for hedgehogs, wrens and insects.
Common mistakes
- Clipping without first checking for nesting birds.
- Cutting back into bare brown wood: it will not regrow from there.
- Pruning too much: it grows best when left alone.
- Leaving a stub or sawing flush with the trunk: cut just outside the branch collar.
Caution: Susceptible to green spruce aphid: in spring, brown needles drop from the inside of the tree.
Nearby: related pruning guides
Similar to: Difference from Norway spruce
Plant profile: Colorado blue spruce · Pruning calendar and basic rules
This guide is compiled from the Bladwijzer plant profile and pruning calendar.