How deep should a wildlife pond be?

A wildlife pond should have a maximum depth of at least 60cm (2ft) to prevent freezing solid in winter. Include shallow margins (10-20cm) for wildlife access and planting shelves at 20-30cm depth for marginal plants. Varied depths create the best habitat diversity.

What size liner do I need for a pond?

Liner size = pond length + (2 x max depth) + (2 x overlap). The overlap (usually 30cm each side) allows for securing the liner at the edges. Always round up and buy slightly more than calculated to allow for uneven ground.

Do I need a pump for a wildlife pond?

A dedicated wildlife pond does not strictly need a pump if it has a good balance of plants and receives some natural water circulation. However, a pump improves water quality and oxygenation. Size it to circulate half the pond volume per hour.

What is the best shape for a wildlife pond?

An irregular or kidney shape is most natural-looking and provides varied habitat zones. Include at least one gently sloping side for wildlife access, a shallow shelf for marginal plants, and a deeper central zone. Avoid steep sides.

How many plants does a wildlife pond need?

Aim for around two-thirds of the pond surface covered by plants. Include oxygenating plants (one bunch per square metre), marginal plants on the shelves, and a few floating plants. This creates a balanced, low-maintenance ecosystem.

GardenCalcs

Wildlife Pond Calculator — Volume, Liner & Pump Size

Calculate the volume, liner size, underlay, and pump requirements for a wildlife pond.

Pond Length

For circular ponds, enter diameter

Pond Width

Ignored for circular ponds

Maximum Depth

Maximum depth in m

Pond ShapePond shape

How We Calculate This

How The Calculations Work

Volume: Length x Width x Depth x shape factor (0.75 rectangular, 0.667 kidney/circular)
Liner: (Length + 2 x depth + 2 x overlap) x (Width + 2 x depth + 2 x overlap)
Pump size: Half the pond volume per hour (litres/hour)
Planting shelf: Perimeter x shelf width

Frequently Asked Questions

Related Calculators

Pond Pump Calculator

Calculate pump flow rate needed based on pond volume, head height, and feature type.

Last updated: March 2026

All calculations are estimates based on standard gardening guidelines. Results may vary with soil conditions, climate, and plant varieties.