How deep should bark mulch be?

For general decorative purposes, 50mm (2 inches) is sufficient. However, for effective weed suppression, we recommend a depth of at least 75mm to 100mm (3-4 inches).

How many litres are in a standard bag of bark?

Most large bags sold at UK garden centres (like B&Q or Homebase) are 70 litres. Smaller bags may be 50 litres.

What is the difference between bark mulch and woodchips?

Bark mulch is made from the outer layer of trees; it breaks down slowly and looks more natural. Woodchips are made from the inner wood; they are lighter in color and break down faster, often depleting nitrogen from the soil as they do so.

When is the best time to apply mulch?

Mid to late spring is ideal, when the soil is starting to warm up but still retains moisture from winter. This 'locks in' the moisture for the summer months.

How deep should bark mulch be?

For general decorative purposes, 50mm (2 inches) is sufficient. However, for effective weed suppression, we recommend a depth of at least 75mm to 100mm (3-4 inches).

How many litres are in a standard bag of bark?

Most large bags sold at UK garden centres (like B&Q or Homebase) are 70 litres. Smaller bags may be 50 litres.

What is the difference between bark mulch and woodchips?

Bark mulch is made from the outer layer of trees; it breaks down slowly and looks more natural. Woodchips are made from the inner wood; they are lighter in color and break down faster, often depleting nitrogen from the soil as they do so.

When is the best time to apply mulch?

Mid to late spring is ideal, when the soil is starting to warm up but still retains moisture from winter. This 'locks in' the moisture for the summer months.

Bark Mulch Estimator

Calculate exactly how many bags of mulch you need for your borders.

Coverage Area (m²)

Mulch Depth (mm)

50mm

Quantity Required

Gardening Tip: Always lay a **permeable weed membrane** before applying bark mulch. This prevents weeds from coming up through the soil while allowing water and nutrients to reach your plant roots.

The UK Guide to Mulching Borders

Healthy Soils

Mulching is one of the most beneficial things you can do for your garden. It suppresses weeds, retains moisture during dry spells, and improves the soil structure as it slowly breaks down over time.

Using our **bark mulch calculator** helps you avoid under-ordering, which leads to patchy coverage, or over-ordering, which results in unsightly piles of unused woodchip on your driveway.

Coverage Rates

1 x 70L Bag~1.4m² @ 50mm

1 x Bulk Bag~14m² @ 50mm

Weed ControlMin 75mm Depth

Best Practices

Before applying mulch, ensure you have removed all existing perennial weeds. Laying mulch over established weeds like dandelions or nettles will not stop them; it may even help them grow by keeping their roots moist.

Leave a small gap around the stems of woody plants and trees. Piling mulch directly against a trunk can cause the bark to rot and invite fungal infections.

Pro Tip: Decorative Finishes

If you are mulching for purely decorative reasons in a formal garden, consider using **Ornamental Bark** or **Slate Chippings**. If you are mulching a utility area or a woodland path, **Play Grade Bark** or **Woodchips** are more durable and cost-effective.

Mulch & Border FAQ

Ordering Guide

Bulk bags are almost always cheaper than individual 70L bags if you need more than 0.5m³. However, they are delivered on a pallet and usually dropped at the kerbside, so factor in the labor of wheelbarrowing it to your borders.