Q: Why mulch and feed, and what is the difference?
A: Read on!

What is mulch and why use it?

Mulch is a loose layer of material spread on the surface of cultivated soil in garden beds and borders and containers. It helps the soil hold moisture in hot and dry weather and protects plant roots from cold weather. It helps keep weeds down and out, and can deter some pests. Some mulches rot down to improve the soil and feed your plants. Some keep edible plants clean by adding a barrier between the plant and the soil. They can help your garden look very smart!

The who's who of mulches

1. Biodegradable mulch

Includes leaf mould, garden compost, old mushroom compost, seaweed, wood chippings and the processed bark from conifers (which can make your soil more acid), well rotted manure, straw (for strawberries) and used hops (BEWARE these are poisonous if eaten by dogs). All these break down gradually to improve your soil by adding texture and nutrients.

The snag? You need to add a layer each year or so. Seen another way that is a bonus. Think of the good it is doing your garden!


This store of well rotted garden compost at Montacute is larger than most gardens can hold - but it's great stuff. Read our blog on how to do it in your garden. Moira Stone.

2. Non-biodegradable mulch

Includes slate, shingle, pebbles, gravel, stone chippings and many other aggregates. These mulches don’t improve the fertility or structure of your soil, but do suppress weeds, help keep moisture in and the effects of cold out, and may look smarter than biodegradable mulches.

The snag? You need to keep them looking tidy and a top-up every few years often helps.

Sheets of woven weed suppressant fabric do a mulch job too. They are good for covering new beds or borders and protecting a lot of edible plants. You cut slits in the sheet and dig your plants into the soil beneath. If you don’t like the look - cover the sheet with another non biodegradable mulch.

The snag? Shreds of fabric can come loose and flap about – weigh them down or cut them off. As your plants spread you may want to remove the fabric and / or the extra layer of much. Not difficult, but a job to be done.

When and how to mulch?

Soon! As the ground warms up in spring and through the summer. Don’t add mulch when the soil is very cold. Weed your patch before you add mulch. Spread biodegradable mulches to a depth of at least 5cm (2in), and ideally 7.5cm (3in). Spread around plants, keeping off trunks and stems. For large shrubs and trees spread the mulch as far out as the widest area of their branches. New plants still need to be watered.

What does ‘feed your garden’ mean? And why should I do it?

Adding nutrients to your soil through compost or manure, or directly to your garden plants through a fertiliser, supports healthy growth and makes the best of your plants. Usually soil and plants in containers and the plants that give you flowers, fruit and veg. do better when you feed them. Sandy and chalky soils are likely to benefit more from manures that feed the soil than clay or loams.

garden fertiliser

Bewildered by fertlisers? Read the labels before you buy or use any. Sarah Buchanan.

How and when to feed your garden

As they rot, biodegradable mulches feed your soil. You may need to do more or different things to feed your garden. First choose a fertiliser to match your plant and its needs. There are four main groups.

Top dressing: add fertiliser to the soil surface around plants to stimulate good growth.

Base dressing: integrate fertiliser in soil before sowing or planting to support good growth. Some need to be added in the winter or early spring, others during the growing season.

Watering on: add feed to plant roots during the growing season, giving an instant boost.

Foliar feeding:  apply a dilute solution of feed to leaves, giving an instant boost.


Q: What next?
A: Sit back and enjoy the show!

feed mulch

Enjoy summer rewards from spring action to mulch and feed. Sarah Buchanan.