How to prune a young eucalyptus gunnii: complete guide to cider gum

Why prune a young eucalyptus gunnii?

Eucalyptus gunnii (cider gum) is an Australian tree that grows extremely fast: up to 1-1.5 meters per year. This sounds good, but without pruning your tree becomes floppy, one-sided, and breakable. The trunk does not build strength quickly enough. With deliberate pruning in the first year, you create a sturdy framework, stimulate denser branching, and prevent the characteristic "weak stick" that plagues many young eucalypts.

Eucalyptus gunnii is also special for its young, blue round leaves. Pruning keeps this juvenile form longer, which is visually attractive. Without pruning, the tree quickly switches to adult, elongated green leaves.

TL;DR: Young eucalyptus pruning in two steps

1. March-April: Cut the central leader back to 40-60 cm so side shoots develop.
2. July-August: Light summer thinning of conflicting branches.

Eucalyptus gunnii pruning: timing and techniques

Eucalyptus gunnii grows March through October. It has no real winter dormancy. Prune in March-April (main work). July-August for summer work. Never after September; new growth is frost-sensitive.

Step 1: Cut back the central stem (year 1)

This is the core work. In the first spring (March), cut the main stem hard. This forces the tree to produce side shoots instead of continuing upward.

Practice: Cut the stem back to roughly 40-60 cm above ground. This sounds drastic, but it works. The tree will now devote energy to side shoots.

Bud orientation: Always cut just above a bud facing outward (not toward the stem). This stimulates outward growth.

Step 2: Select primary skeleton branches (year 1)

After two weeks, side shoots will emerge where you cut. Once they are roughly 10-15 cm, select the four to six strongest. These become your primary branches.

Selection: Choose branches distributed evenly around the stem, growing at good angles (45-60 degrees). Remove all other side shoots.

Step 3: Cut back primary branches (year 2)

In year two (March again) cut the primary branches back to roughly 30 cm. This stimulates further branching. Your tree now becomes more bush-like instead of one weak stem.

Careful: Eucalyptus recovers quickly from pruning, but never remove more than one-third in one cut.

Step 4: Thin out for open structure

Eucalyptus gunnii produces many branches. Too-dense foliage creates moisture problems. Thin lightly so your tree does not become a "cloud", but retains open form.

Technique: Remove some conflicting branches. Do not thin heavily; eucalyptus recovers from heavy cuts, but lots of maintenance is labor-intensive.

Year-1 to Year-3: the build-up phase

• March year 1: Cut back to 40-60 cm. Select primary branches as they grow.
• July year 1: Light thinning if needed.
• March year 2: Cut primary branches back to 30 cm.
• March year 3: Less drastic pruning now. Maintenance work: remove dead branches and thin carefully.

The "floppy tree" problem

Many young eucalypts become floppy because they grow too vigorously upward without side shoots. They develop one long, thin stem that starts to sag under its own weight. This is prevented with early, heavy pruning. Do not wait until your tree is already 2 meters; prune when it is young (first year).

Frequently asked questions

When does eucalyptus gunnii lose those beautiful blue leaves?

Normally it switches to adult green leaves after roughly 2-3 years of growth. Regular pruning (especially cutting back branch tips) can slow the process slightly, but not stop it entirely. This is normal.

How fast does eucalyptus gunnii really grow?

1-1.5 meters per year in good conditions. This is indeed very fast. This is why early pruning is so important - you do not want this fast growth going every direction.

How large will eucalyptus gunnii be in 10 years?

This tree can reach 15-20 meters. In mild climates it can get larger. This is why structure from the start is critical - you are building for a large tree.

Can I keep eucalyptus gunnii as a shrub?

Yes, with regular heavy pruning. But this requires annual hard cutting (as described in the next article: coppicing). A natural tree is less labor.

My eucalyptus gunnii is already 2 meters, floppy, and one-sided. Can I fix it?

Yes, but it is tougher work. Cut hard back to older, stronger wood (it may look rough), so it regenerates from below. This costs some height, but you get much better form after.

Step-by-step

Step 1: Assess your tree current state

In March of year 1, note: How tall is the tree? Does it grow straight up or is it sagging? Are there any side shoots?

Step 2: Cut back to 40-60 cm

Cut the central stem back with one clean cut. Cut just above a bud facing outward.

Step 3: Wait for side shoots

Over the next 2-4 weeks, side shoots will emerge where you cut. Let them grow to 10-15 cm.

Step 4: Select the best side shoots

Choose four to six strong, evenly spaced side shoots. Remove all others.

Step 5: Support the growth

Young eucalypts can sag in windy conditions. Provide sturdy support and soft ties so the tree develops with stability.

Eucalyptus varieties: differences

Eucalyptus gunnii: Fastest grower, hardiest for cold climates. Blue juvenile leaves. This article.

Eucalyptus pauciflora: Slower, smaller tree, more cold-tolerant.

Eucalyptus nicholii: Narrow-leaf, vigorous, fine foliage, moderate grower.

Frequently asked questions

Should I water my young eucalyptus?

Yes, especially year one. Eucalyptus gunnii grows fast and needs lots of water when young. Water regularly the first two seasons.

Eucalyptus loses leaves after pruning. Normal?

Yes, sometimes. They can shock from heavy cuts. Water well and feed. The tree recovers.

My eucalyptus grows very floppy. What can I do?

Usually too much wind and insufficient support. Provide a sturdy stake (at least 2 meters tall). Also cut back to older wood so it builds stronger branches from below.

Can I use eucalyptus as a hedge?

Not really. They become far too large and fast-growing. Better for specimen use.

Discover your garden with young eucalyptus

At [gardenworld.app](https://gardenworld.app) you can see how a young eucalyptus gunnii fits in your front yard - with realistic growth shapes and surrounding plantings. Plan your structure before you reach for the secateurs.