How to prune hedge in first year: forming and basic structure

Why first-year pruning is critical

Many gardeners look at their new hedge and think: "Let it grow, I'll trim next year." This is a mistake. Year 1 determines everything. The pruning steps you take now define whether your hedge in 20 years is tight and compact, or wide and uneven.

A young hedge (newly planted, or 1 year old) grows wild. All energy goes up and sideways. Without pruning you get:

• Bare gaps at bottom (sparse-base effect)
• Irregular width (wider top)
• Poor interior density
• Difficult to fix later

With strategic first-year pruning you build a "skeleton" that carries forward for life.

First-year timing: when do you start?

This depends on planting timing:

Spring planted (March-April):

• Wait until June to start pruning (tree needs time to settle)
• June: first trim
• August: light trim
• Stop pruning after September (tree must build strength for winter)

Autumn planted (September-October):

• NO pruning in autumn/winter
• Wait until March next spring
• Then start first-year pruning

Summer planted (July-August):

• Very cautious in August only
• Prefer waiting until March next year

Golden rule: Prune young hedge minimally the first season. You want to stimulate growth, not slow it.

Step 1: inspection and goal setting

Before you start, decide: what shape do you want?

Rectangular profile (most formal):

• Vertical sides, flat top
• Requires more maintenance, very tight
• Work: annual trim needed

Trapezoid/tapered (wide bottom, narrow top):

• More light at bottom
• More rustic look
• Less intense maintenance
• RECOMMENDED for year 1

Triangle/pointed (peaked top):

• Water drains perfectly
• Classic look
• Much work to maintain point

For year 1: trapezoid shape is best choice. It gives you the most stable base and least work.

Step 2: determine desired dimensions

Measure and note:

• Desired final height: (e.g. 1.8 m, 2 m, 2.5 m)
• Desired width bottom: (e.g. 80 cm, 1 m, 1.2 m)
• Desired width top: (20-30 cm narrower than bottom)

This depends on your garden, neighbors, views. Fix this. You will work toward this over next years.

Example:

• Final height: 1.8 m (eye level)
• Width bottom: 1 m
• Width top: 40 cm (tapers upward)

Step 3: first pruning (June, year 1)

For thuja or mixed hedge (usually cautious):

1. Inspect sides: where does growth look strangest?
2. Gently trim drooping branches far from profile
3. Depth: only 2-3 cm (shallow!)
4. Top: let it grow, do not trim

This is mainly making space and correcting irregularities, not hard forming.

For thuja/Smaragd (columnar):

• Is your top already shaped well? Let it grow
• Sides gently trimmed, but not cut hard back
• Goal: only very protruding branches off

For Brabant or wider type:

• Sides can be trimmed more cautiously
• Width can grow, we mostly trim height and symmetry
• June: cautious, August can be slightly more

Step 4: August second touch (optional, fast-growing types only)

If your thuja or cypress grows very fast (30+ cm in two months):

1. Light side trim
2. Front check for symmetry
3. No hard pruning
4. Remove drooping branches
5. STOP after August, no September pruning

This gives your hedge more shape mid-season. Not mandatory.

Step 5: late-summer monitoring (September-October)

Look at your hedge:

• Growing evenly on both sides?
• Top still reasonable?
• Drooping branches?
• Gaps at bottom visible?

No pruning, but make notes. These are your takeaways for next March.

Preventing bottom gaps: critical rule

Many young hedges have bare bottoms by year 2. This is caused by:

1. Insufficient bottom-branch selection: You trim top only, bottom branches grow wild
2. Poor light at bottom: Not enough light reaches below - leaves drop
3. Back-to-front growth: Branches grow one layer dense behind another, no horizontal spread at bottom

Prevention in year 1:

• Ensure bottom 30 cm always stays wider than top
• Never cut sides vertically; always angled (wider below)
• Let bottom branches grow more than top branches
• Ensure trapezoid shape

This is the secret of full hedges from bottom to top.

Thuja vs. Leyland cypress: form difference year 1

Thuja (Smaragd, Brabant):

• Grows more vertical, less sideways
• Can be cut more cautiously
• Trapezoid shape requires more side trimming
• August trim is OK

Leyland cypress:

• Grows aggressively sideways
• Very shallow trimming (3-5 mm only)
• Trapezoid shape forms faster naturally (you do less)
• NO August trim, June only

Juniper (juniperus):

• Slow grower
• Minimal first-year pruning
• Let almost everything grow, shape follows
• Second-year forming better

First-year frequently asked questions

My hedge grows lopsided - one side wider. What now?

This is normal. Side may get more sun, or variation in soil quality. Trim the wider side slightly more (1-2 cm deeper). Next year it will even out.

Can I prune my hedge in May?

Better not. Too early in season. June is safer - tree has built more strength. May pruning can slow growth.

Must I make my hedge neat for guests? It looks untidy in June.

No. Year 1 can look messy. This is investment phase. Neat hedges are year 3+ work. Be patient.

My hedge looks thinner after June pruning. Is that normal?

Yes. You removed volume. It looks thinner, but it regrows fast. June-July-August: heavy growth. Early September: full again.

How young is "young" really? When does first-year phase end?

Usually:

• Year 1: foundational forming
• Year 2: further refinement
• Year 3+: maintenance phase (annual trim)

But a small hedge plant can be year 1-2, a large one maybe only first few months. Use: height determines. < 1 m tall = mainly first-year phase.

My hedge is already 1.5 m when planted. Is this still first year?

Yes. Regardless of size: first 12 months after planting = year 1 forming. Same rules apply.

Step-by-step first-year hedge forming

Step 1: Plan shape and dimensions

Choose trapezoid. Note: final height, width bottom, width top.

Step 2: Inspection (June)

Look at growth. Symmetry? Drooping branches?

Step 3: First pruning (June, minimal)

Sides carefully; drooping branches off. 2-3 cm depth max. Let top grow.

Step 4: August check (optional)

Fast-growing hedges: light trim. Others: wait.

Step 5: September-October monitoring

No pruning. Take notes for next March.

Step 6: October-December growth

Let growth continue. Tree builds energy reserves for winter.

Cultivar preferences

Thuja Smaragd:

• Very upright. Trapezoid shape requires attention.
• Year 1: very shallow trimming.

Thuja Brabant:

• Naturally wider. Trapezoid forms more easily.
• Year 1: sides can be cut more (cautiously).

Leyland cypress:

• Grows wild, lots of sideways.
• Year 1: very cautious, only drooping branches.
• NO August pruning.

Boxwood/Yew (fine woodwork):

• Slow. Year 1: minimal pruning.
• Forming starts year 2.

Privet:

• Fast-growing. Year 1: can be cut more.
• Trapezoid requires attention but forms fast.

Conclusion: patience wins

First-year hedge forming is patience. You do little, you wait much. This goes against instinct (you want immediate neat shape). But this patience pays off: by year 3-5 you have a hedge that is tight, full and healthy without constant work.

The foundation built in year 1 determines decades. Do it right now, and your hedge thanks you later.

Discover your garden design

At [gardenworld.app](https://gardenworld.app) you can upload your front yard and see how your young hedge grows into it. Plan your hedge shape, see plant combinations, and visualise your front yard's future.

First-year pruning: minimal work, maximum impact.