Everything you need to know about Bark & Mulching
Why and how you should be adding mulch to your garden
The importance of soil and the issue of soil erosion is something that is hitting the headlines more and more. As frequencies of rainfall shift, localised floods develop new patterns and severe storm events become something we all have to grapple with. But are you aware that the soil quality in your garden can be impacted in much the same way?
The best way to protect and improve the quality of your soil and to maintain plant health is to add mulch. Available in a variety of materials, adding mulch not only protects and enriches the soil with useful elements, but helps retain moisture in the soil, reduces weeds and encourages the growth of roots, which in turn helps prevent localised soil erosion.
Mid to late spring and autumn are usually the best times for mulch application
Adding more mulch later in the year will help protect the soil in your garden from weathering, leaching and freezing, which will all help plant development for the coming year.
Mulch comes in several forms
You can use raked leaves and even grass clippings as organic mulch material or you can buy bark mulch, wood chips or even add stone chips; each brings its own aesthetic to your garden. Mulch material can change the visual geometry of a garden, and the ‘right’ mulch can create decorative visual sweet spots in different zones of your garden. You might use decorative stone ships to the front but add grass clippings to the vegetable patch in the back garden, for example.
If you are focused on organic gardening, mulching helps preserve the natural nutrition of your soil layer. Far from being a job left incomplete, it can be an advantage to leave some autumn leaves and root material after an autumn harvest. But do loosen the soil, add compost and then put a layer of mulch 6-8cm deep for maximum protection of your topsoil throughout the winter frosts.
Pay particular attention around the roots of fruit trees and berry bushes. In winter they can suffer from frost, especially in cold, snowless winters. Therefore, add mulch to the perimeter of the crown. The same is true for perennial ornamental plants.
4 ways bark will help alleviate the impact of extreme weather?
- Bark spreads rainwater so that it can permeate the soil more evenly, and also reduces evaporation significantly.
- It acts as a layer of insulation, protecting any plant roots from extreme weather temperatures throughout the year.
- Bark shades weed seeds from the sunlight they need to grow. The coarser the bark the bark, the greater its weed suppression capacity. It’s important to note that any established plants with strong shoots or bulbs, such as crocuses and snowdrops, will grow through as normal.
- It releases a range of nutrients as it decomposes which will enhance your soil’s fertility.
Frequently asked questions
1) How long does bark last?
Bark breaks down slowly and will not need replenished often – some mulches can still be effective years after they were added. However, routine top ups when soil shows through, and a replenishment of bark mulch every 2-3 years, will maintain its full benefits.
Be careful not to lay too thickly as this can deprive the soil and plant roots of oxygen; or too thinly, as this will increase the soil’s exposure to sunlight and may hinder weed control.
2) Can I plant bedding plants amongst mulch?
Bedding plants thrive in soil that’s protected by mulch from severe weather fluctuations.
3) Can the soil still breathe below bark?
A soil with good structure will have a soil atmosphere – air space between soil particles – and this isn’t adversely affected by adding mulch; but do break up the soil before you add the mulch.
4) Does a bark mulch help combat plant disease?
Experiments show a number of plant root diseases are inhibited using bark as mulch – including Rhizoctonia, Pythium, Phytophthora, Tomato Root Knot and Forsythia Parasitic Nematodes.
5) Does adding bark make the ground acidic?
Because bark lies on the soil surface, it allows for the passage of rainwater and air into the soil, and therefore has no harmful effect on the soil’s pH.