Everyone’s talking about mulch, but why should you use it? What actually is it? And how should you apply it?

In a nutshell, mulch is a protective layer of material spread over the soil surface to conserve moisture, suppress weeds, regulate soil temperature, and improve soil structure. It's like a cosy blanket for your garden, and contributes to a healthy ecosystem.
Why should you mulch?
1. Temperature Regulation: Mulch serves as an insulator helping to maintain stable soil temperatures. This protects plant roots from extreme fluctuations that can damage their delicate structures. If you’ve got plants which are a little less hardy, a good layer of mulch overwinter can greatly increase their chances of pulling through, without you having to go to the trouble of lifting and storing them.
2. Weed Suppression: Mulch effectively hinders weed growth by blocking sunlight from reaching their seeds, preventing germination and growth. This reduces competition for nutrients and water, allowing your desired plants to thrive.
3. Soil Structure Enhancement: Mulch works its magic by breaking up compacted soil, improving aeration and drainage. This facilitates root penetration and nutrient uptake, promoting healthy plant growth.
4. Erosion Control: Mulch acts as a shield, protecting the soil surface from weather erosion. This prevents the loss of valuable topsoil and nutrients, preserving the fertility of your garden.
5. Nutrient Addition: As mulch decomposes, it releases organic matter and essential nutrients into the soil, enhancing fertility and providing a slow-release source of nourishment for plants.
6. Water Conservation: Perhaps more relevant in spring/summer, but mulch acts as a barrier, reducing evaporation and conserving soil moisture. This is particularly crucial during dry periods, ensuring that plants receive adequate hydration and preventing wilting.
Sounds good right? But what materials can you use as mulch?
The most suitable type for your garden will depend on your individual circumstances and preferences, as well as the needs of your garden. But here are a few of the usual suspects:
Leafmould: This rich, humus-like material excels in improving soil structure, water retention, and fertility. It is also a good choice for suppressing weeds. And it’s free! At least it is if you make your own.
Manure: A high-nutrient mulch, manure is excellent for water retention and weed suppression. Make sure you use well rotted manure as the fresh stuff can cause nutrient burn, spread weed seeds and tbh, doesn’t smell great!
Straw: A good choice for mulching around vegetable plants, straw provides organic matter and suppresses weeds. However, it breaks down quickly and requires frequent reapplication.
Bark Chip: A low-nutrient mulch, bark chip is not as effective at suppressing weeds. However, its durability makes it suitable for mulching around woody plants. Looks great in a woodland type setting, but I’m not a huge fan of the American-style all border bark mulching.
Compost: A versatile mulch, compost excels in water retention, weed suppression, and soil structure improvement. It provides a rich source of nutrients for plants. Cost-effective if you make your own, but obviously more expensive if you’re buying it in.
Cardboard: Effective at suppressing weeds, cardboard is not nutrient-rich and needs removal before planting new growth. Make sure you wet it and weigh it down. It’s a good one for creating new borders, but a bit trickier to lay around existing plants.
Finally once, you’ve chosen your mulch, how should you apply it?
Prep: Before applying mulch, make sure the soil is moist (shouldn’t be a problem at the moment!). This helps the mulch settle evenly and prevents it from absorbing moisture from the soil, which could dry out plant roots.
Depth: Apply a layer of mulch around 2-3 inches thick. Better to do a smaller area well than a larger area to thinly. That said excessive mulch can suffocate plants and restrict their growth.
Space: Don't mulch right up to the base of woody plants, leaving a gap of a few inches between the mulch and the trunk. This allows for air circulation and prevents the mulch from promoting fungal diseases that can harm the plant's bark.
Picture credit:
Image by Jenny Johansson from Pixabay