Japanese maple care guide: when & how to prune, fertilize and spray

When: 3–8 weeks before the last spring frost.

• zones 3–5: about Mar 15 – Apr 19
• zones 6–7: about Feb 18 – Mar 25
• zones 8–10: about Dec 31 – Feb 4

With the leaves off, you can see the branch structure clearly. Cut while dormant, before the sap starts flowing, to avoid heavy sap bleeding.

1. Remove dead, broken and crossing branches first.
2. Remove branches that grow straight up or straight back into the center.
3. Thin crowded areas so each horizontal layer is visible. Remove no more than 10–15% of the canopy in a year.
4. Cut back to a side branch or the trunk, just outside the branch collar. Don't leave stubs or flush cuts.
5. Remove green-leaved shoots from below the graft on grafted red varieties.

Tools: Bypass pruners, Small pruning saw

When: from the last spring frost to 3 weeks after.

• zones 3–5: about May 10–31
• zones 6–7: about Apr 15 – May 6
• zones 8–10: about Feb 25 – Mar 18

Japanese maples need little fertilizer. Too much nitrogen causes weak, floppy growth.

1. Top-dress with compost, or apply an organic tree fertilizer at half the label rate.

What to use: 🌿 Finished compost or composted manure · 🌿 Organic tree & shrub food (e.g. Espoma Tree-tone 6-3-2)

When: 2–6 weeks after the last spring frost.

• zones 3–5: about May 24 – Jun 21
• zones 6–7: about Apr 29 – May 27
• zones 8–10: about Mar 11 – Apr 8

Mulch keeps roots cool and moist, suppresses weeds and slowly feeds the soil. Applying it after the soil warms lets roots wake up first.

1. Spread 2–3 in (5–7 cm) of mulch over the root zone.
2. Keep mulch 2–3 in (5–7 cm) away from stems and trunks. Mulch piled against bark invites rot and rodents.
3. Don't go deeper than 3 in (7 cm) in total. Too much mulch suffocates roots.

What to use: 🌿 Shredded hardwood or pine bark mulch