We mulch to improve the soil and help retain water during the hot summer months, as well as protect the plants during cold winter frosts.
Everything in your garden will benefit from regular applications of mulch.
So when is the best time to mulch? Spring and fall are probably the best times but it very much depends on what is in your garden beds as well as your climate.
What Are The Benefits Of Mulch?
Why do we mulch our gardens? There are many benefits to mulching our gardens:
- suppresses weeds
- improves the fertility of the soil if using organic mulch
- helps to retain moisture so saves on watering
- regulates the soil temperature - cool in summer and warm in winter
- improves structure and soil drainage
- protects the soil against erosion
- mulching covers the ground when plants are spaced quite far apart
Is It Better To Mulch In Spring Or Fall?
That depends. Does your soil freeze in the winter? Do you have a large number of perennials that need cutting back in fall? Or perennials that need to protect the plant from frost until early spring? What type of mulch are you using?
There are merits to both seasons. I usually only use compost as a mulch as I make my own free compost in various ways. I mulch in both seasons and inbetween when needed, such as planting up a new bed.
Applying Mulch In Fall
- The extra layer of mulch will protect the plants in regions that have a harsh winter.
- Keeps the soil, microbes, earthworms and other beneficial soil creatures insulated.
- Roots that are near the surface are protected from freezing.
- Fall mulch keeps the soil warm while the weather is still warm and cools down more slowly when the cold arrives.
- Organic mulch is broken down by the micro-organisms living in the soil. However, in winter, most have gone dormant; therefore, woody material such as untreated wood chips spread thickly is an excellent mulch for the fall in regions where the soil will freeze.
- Mulching over fall-planted bulbs will help them get ready for their next season.
- Mulching in fall creates ideal conditions in the soil over winter for when plants spring to life again.
- If using shredded leaves, leave the leaf debris in the beds and add organic mulch on top. The mulch will hold the leaves in place, and it provides a second degree of insulation.
- Fall mulching will keep the soil moist and weed populations down.
Applying Mulch In Spring
- Mulch in spring when your garden is starting to wake up from winter and all chances of frost have passed.
- A layer of mulch in the spring over your landscaped beds will give your plants a great start to the growing season.
- Early spring mulch warms the soil and gives your bulbs, plants and seeds an excellent environment for the new growth.
- Mulch will moderate the temperature as they heat up.
- Sun and wind can suck the moisture out of the soil, and mulching in spring will eliminate this.
- Weeds will not be able to germinate under the mulch without sunlight.
- Mulch improves the soil, especially when it rains as the mulch will protect the soil from soil erosion.
How Often Should I Mulch?
Mulching does not have to be for fall or spring only. Mulching can and should be applied at any time of the year.
- Putting down a mulch layer in late winter (in areas that do not have snow) will suppress weed seeds from germinating in the early spring
- Some organic mulch, such as compost, weed-free straw and shredded leaves, decomposes quickly compared to others such as bark chips. Those that compost quickly will need to be topped up with a thin layer every 2-3 months.
- The rate the mulch decomposes will depend mainly on your climate. A temperate climate with moderate sun exposure will decompose quicker than a cold climate with low sun exposure.
When To Mulch A Vegetable Garden
In spring and fall, natural organic mulch is both ideal times to prepare your soil and add the vital nutrients for your upcoming veggie crops.
Reapplying Mulch To Your Vegetable Garden
Once the mulch has started to breakdown on your veggie garden, top up with an inch (2.5cm) of compost or have some leaf mold available just to build your soil and keep the benefits of mulching.
Another time to lightly apply more mulch is when you see weeds growing. Pull out the weeds and leave them lying on the mulch before replying mulch or use a thicker layer over the growing weeds to smoother them.
If using organic mulch, always use a good quality weed-free non-toxic mulch.
Most organic mulches that compost quickly will need to be added in fall and spring.
About 2-2.5 inches (5-7.5cm) is adequate for organic mulch, and about 1.5-2 inches (4-5cm) inorganic mulch is recommended. It is not necessary to overdo it.