How Many Plants Do You Need for a Hedge?
Planning a hedge and wondering how many plants to buy? The answer comes down to one variable: spacing. Enter your total hedge length and choose a plant species — the calculator applies the correct spacing for that species and gives you the exact quantity to purchase, already rounded up so you never run short.
To calculate hedge plants, divide the total length (in meters) by the spacing between plants: plants = meters ÷ spacing. Thuja needs 1 plant every 0.8 m (≈1.25 plants/m), privet 1 every 0.4 m (2.5 plants/m), and bamboo 1 every 1 m. For a 10 m hedge with thuja, you need 13 plants (always round up).
When to use this calculator
- Residential privacy hedge projects
- Professional landscapers pricing a job
- Verify quantity before visiting the nursery
- Compare species by total plant count and cost
- Budget planning for hedge installation
- School or community garden hedge projects
Worked Example: 10 m Thuja Hedge
- Hedge length: 10 m
- Thuja spacing: 0.8 m between plants
- 10 ÷ 0.8 = 12.5 → round up → 13 plants
How it works
1 min readHow to Calculate the Number of Hedge Plants
The formula is straightforward:
> plants = ⌈ length (m) ÷ spacing (m) ⌉
Always round up (ceiling) — you need a whole plant at the last position even if it lands short of the endpoint.
Species Spacing Reference Table
| Species | Spacing | Plants per metre | Plants for 10 m | Plants for 20 m | Plants for 50 m |
|---|---|---|---|---|---|
| Thuja | 0.8 m | 1.25 | 13 | 25 | 63 |
| Privet | 0.4 m | 2.5 | 25 | 50 | 125 |
| Bamboo | 1.0 m | 1.0 | 10 | 20 | 50 |
Why Spacing Matters
Thuja (Thuja occidentalis / western red cedar): slow-growing, dense evergreen. Space 0.8 m apart so crowns eventually touch and form a solid wall. Standard for tall privacy screens (2–5 m). One annual trim keeps it tidy.
Privet (Ligustrum vulgare): fast-growing, semi-evergreen. Close 0.4 m spacing allows the dense interlocking canopy that makes privet famous for impenetrable hedges. Requires trimming every 4–6 months.
Bamboo (Phyllostachys / clumping types): fastest growing of the three. Space 1 m apart — clumps spread to fill gaps within 2–3 seasons. Always use a physical rhizome barrier (40–60 cm deep) to prevent runners spreading beyond the intended line.
Practical Tips
Frequently asked questions
How many plants do I need per metre of hedge?
It depends on the species. Privet: 2.5 plants/m (0.4 m spacing). Thuja: 1.25 plants/m (0.8 m spacing). Bamboo: 1 plant/m (1.0 m spacing). Multiply your hedge length by the plants-per-metre figure and always round up.
What spacing should I use between hedge plants?
Standard landscape spacing: Thuja 0.8 m, Privet 0.4 m, Bamboo 1.0 m. Tighter spacing fills in faster but increases cost. Looser spacing saves money but leaves visible gaps for 1–2 extra seasons.
How many thuja plants do I need for a 10-metre hedge?
13 thuja plants. The calculation: 10 m ÷ 0.8 m spacing = 12.5, rounded up to 13. For 20 m you need 25, for 50 m you need 63.
How many privet plants for a 10-metre hedge?
25 privet plants. Privet is spaced at 0.4 m: 10 ÷ 0.4 = 25 exactly. For 20 m: 50 plants. For 50 m: 125 plants.
Do I need to round up or down when calculating hedge plants?
Always round UP (ceiling). If the formula gives 12.5, buy 13 plants — you need a plant at that last position even if it falls a bit before the endpoint, or the hedge will have a gap.
Should I plant a single or double row of hedge plants?
Single rows work for most privacy hedges. Double rows create a thicker, more windproof barrier. For a double row, increase your single-row plant count by about 50 % and offset the second row by half a spacing interval.
Does bamboo need a root barrier when planted as a hedge?
Yes, for running bamboo (Phyllostachys species). Install an HDPE root barrier at least 40–60 cm deep along both sides of the planting strip before planting. Clumping bamboo (Fargesia) spreads much more slowly and may not need one.
When is the best time to plant a hedge?
Autumn (September–November in the northern hemisphere) is ideal: cooler temperatures reduce transplant stress and roots establish over winter. Early spring (March–April) is the second-best window. Avoid planting in summer heat or hard winter frost.
How do I plan a hedge around a corner?
Calculate each straight section separately, then add one extra plant per corner. The corner plant anchors both sides of the turn and ensures the hedge closes neatly at the angle.
Can I use this calculator for other plant species?
The built-in options cover the three most common hedge species. For other plants, use the general formula: plants = ⌈ length ÷ recommended spacing ⌉. Check the nursery tag or supplier guide for the correct spacing for your specific species.