In this step-by-step guide we’ll not only show you how to mulch but explain the different kinds and what will work best for your plants and garden. Mulches are a thin layer of organic or inorganic material placed over a bed or the soil surrounding plants. The more attractive ones may grab your attention and look like a great addition to formal landscaping, but the practical uses are vast.
Mulches are used primarily to improve the soil around plants, reduce weeds, increase fertility, help the retention of moisture and during winter can protect the roots of the plant from damaging frosts. Using the right mulch for your plants can help eliminate the need for chemical pesticides and fertilisers which is fantastic for your garden’s biodiversity. This all contributes to a healthy, great looking garden you can be proud of.
Now that Autumn is approaching it is the perfect time to start planning!
You can roughly separate the different types of mulch into two categories; organic and inorganic.
Organic mulches are best for improving the fertility and overall structure of the soil. Over time the mulch will degrade and replenish the soils nutrients including nitrogen, potassium and phosphorus. Organic material also promotes biodiversity and encourages insects such as worms and spiders which will actually keep pests at bay while further enriching the quality of your soil.
For this reason an organic mulch is fantastic for plants try to establish themselves or are just generally hungry. Roses for example love a good organic mulch of well-rotted manure. More on this to follow.
Inorganic mulches are used to protect the soil around the plant and can also have an aesthetic edge to them. The benefits include locking in water to the soil, keeping weeds at bay and unlike some organic mulches it won’t wash away which is brilliant if you are planting on a slope.
Bark and Wood-Chippings
Here is a mulch which is attractive but also helps improve your soil’s nutrients and structure as it rots down. It also allows water to flow through it without binding throughout the year and really is a fantastic for pretty much all plants and circumstances. The only issue with it is that it is difficult to move or work around and so is best for around trees where you won’t be doing any more planting. Bark and wood-chippings will last you through the year and maybe even two depending on the grade, see how far it has broken down and replace if necessary.
Leaf-mould is arguably the most nutritious and nature-friendly mulch you can apply. Pretty much every plant loves it and what’s more it can be completely free! It may not look like the most attractive mulch but apply in Autumn and by spring it will have blended in with and really enriched your soil. The only major drawback is that leaves do take some while to decompose and if you plan to DIY this is something you plan for a year in advance.
Collect as many leaves as possible in black bags and cut some small holes to let the air in. Ensure the leaves are thoroughly wet as leaves break down through fungi. Come next Autumn you’ll have some of the finest and richest mulch money can buy… not that you have to spend a penny! Of course, leaf mould is available to purchase in fairly substantial bulks.
There are two main reasons why compost can make a great mulch: 1) It is packed full of nutrients ready to leach down into the soil and 2) It is something you can make yourself free of charge. Additionally it helps with keeping the soil moist and fending off weeds. One thing to look out for however is that no weeds have made their way into the compost as these will simply sprout up from the compost and steal your plants nutrients.
As I’ve briefly mentioned before, when it comes to roses and other phosphate hungry plants nothing compares to some well-rotted manure. Like a compost that has gone through a far more strenuous decomposition process it is packed full of nutrients and its dense texture protects the roots and keeps the water locked in. It is also a really great mulch for trees and shrubs although to prevent waterlogging it may be worth mixing with some sand to allow for greater drainage.
Gravel, Slate and Stone Chippings
There really isn’t a great difference here between them as you will want roughly the same thickness of layers. Stone mulches are fantastic for drainage and keep the soil underneath moist. It is also brilliant for retaining heat and so should be used for plants that are used to very hot conditions and can be worked into a Mediterranean themed garden well. Overall many stone mulches look fantastic and can maintain a pristine look for formal garden structures. They do not however add any nutrients to the soil and can become too hot during summer for more tender plants and young trees.
When to Mulch
The best time to apply a mulch is in Autumn, as you come into bare-root season, and spring. You will need to apply the mulch when the ground is relatively warm and moist, avoid periods when it is frozen or waterlogged. When the ground is good to dig and plant, it will be good to mulch which is very handy!
How to Mulch
- Before you apply your mulch first you have to prepare the soil. Clear the ground of any weeds and give it a watering if the soil appears too dry.
- If you are reapplying a mulch now is a good time to break up any old layers which may have matted to allow better water penetration.
- Then cover the ground in a layer of mulch roughly 2 inches thick. Avoid mulching right up to the stems of plants and trees as this can cause them to become soft and rot.
- Level out with a rake to an even finish. This is imperative, some people mulch little mounds, especially around trees. This will cause the bottom of the trunk to grow soft and rot while also drawing water away from the roots.
- If you noticed that your mulch has matted over the year and become a hard layer, simply break and fluff up a bit.
You can apply a fertiliser on top of the mulch through the year if you wish. Follow these rules and you should be all set!
Liam works in the buying team at Primrose. He is passionate about studying other cultures, especially their history. A lover of sports his favourite pass-time is football, either playing or watching it! In the garden Liam is particularly interested in growing your own food.