When you are starting out growing your own plants it can all seem like a lot to learn. But there are a few tricks that expert gardener’s don’t seem to share straight away. Mulch being one of them!
Applying a mulch can offer protection against extreme temperatures as well as aiding water retention in hotter months. Choosing the right mulch for your plant can also mean a boost of nutrients that will aid growth and flowering. Mulching acts as a weed suppressant helping younger plants get established.
Mulch is time saving and can really boost your plants chances of thriving.
What Does Mulch and Mulching Do
It is important to note that not all mulches are created equal and this is a good thing. In general terms this is what some mulches can do for your garden.
- A good mulch will provide protection against the heat of the Summer midday sun. It will also help to retain some of the absorbed heat of the day later into a possibly colder night. Very few plants like to have cold roots.
- Allows soil to retain moisture as it reduces surface evaporation. So this is not ideal if you have plants in a boggy, soggy location and you want it to dry out, but otherwise this is very helpful.
- Some pests are deterred by some mulches. I say this with caution as some pests are encouraged by mulches and you need a little bit more to work around this one. I will go into each mulch type below and work a warning into the suitable place!
- Mulch can lower the frequency with which you have to water your plants. Be sure to bear this in mind and check moisture levels before watering every night in Summer.
- Some mulches have the added bonus of encouraging beneficial soil organisms and giving them a place to live. If this encourages biodiveristy in your garden it will also mean that the soil is better aerated and beneficial bugs and pest are welcome into your garden.
- The right mulch can also provide nutrients for plants. However a word of warning here as certain fruit baring trees like persimmon do not respond well to nitrogen so a mulch like borage would not work well for your harvest!
- If applied after removing perennial weeds and their roots a good mulch can act as a weed suppressant. Plant up your chosen herb, veg or shrub and then lay a generous heap of mulch around each plant it will not allow for those pesky weeds to see the light of day.
- You can use a green manure as a mulch and it will rapidly improve a soils organic matter content, making it better with drainage. Dig it through at the end of the growing season and you will see a very quick improvement on drainage and therefore reduce your chances of root rot.
- Finally a good mulch could also tidy up the look of your garden. It just gives it a clean finish, you know those rose beds you visit at the weekend and really ponder how it looks so formal. I bet they are using a mulch to enhance that neatness.
Not all mulches will be able to achieve all of these qualities so it pays to know what each will do and how to maximize your efforts.
Shredded Or Chipped Bark & Wood As A Mulch
If you have a home chipping machine then make your chippings and then store for a few weeks in a cool dark shed before applying to your garden.
- Great As A Mulch For anywhere that needs tidying up. Bark chippings look formal and work well to keep the soil warm and are biodegradable after a while. So they will not need replacing each season. Bark chips add natural habitat for some beneficial pests in your garden, ones like ground beetles that will eat your aphids! It will regulate heat and protect roots from frosts but also help the soil to retain moisture as well.
- Problems As A Mulch only really if you pile it up around trees or the base of shrubs. This can cause issues as it is great at retaining water. If you want a mulch that will provide fertilizer there are better options.
- Great As A Mulch For anyone with a lawn that they mow regularly! This is a free source of mulch and you should just separate it for a few days before layering it around your garden. Layers should be no thinner than 2 inches and generally speaking the thicker the layer the better. It will regulate heat and protect roots from frosts but also help the soil to retain moisture as well. Biodegradable and a new layer will be required through the growing season. It will add nutrients back to the soil that it has taken when growing as a slow release feed.
- Problems As A Mulch is around if you have seed heads in your lawn this can transfer them to your garden. Dandelions will spread anyway but the mulch layer can then be thickened to prevent the ill effects of any transfer. Avoid clumping your grass cuttings as they are biodegradable and may cause damage to trees or shrubs. Not all plants want a mulch that is also a fertilizer. To balance this out mix in with brown matter like leaves to release carbon and get a more even feed.
- Great As A Mulch For It will regulate heat and protect roots from frosts but also help the soil to retain moisture as well. It is also a free resource and will put nutrients back into the soil as the leaves decay. Great to use around plants that are being overwintered and then harvested in Spring. This means that you can dig in the partially rotted leaves and improve your soil quality and drainage. Leaves are carbon releasing and will go well if mixed as a mulch with grass clippings or similar nitrogen releasing mulch. Leaves are great to cover roses that have been pruned in October with. You can clear them again in teh Spring.
- Problems As A Mulch No real issues with using leaves as a mulch as they are pretty easy to work with and can be worked into the soil once the season has passed. Many bugs will find it a nice home and slugs and snails will aim for leaves that are too fresh, so go for brown and crunchy ones.
Straw / Hay
- Great As A Mulch For It will regulate heat and protect roots from frosts but also help the soil to retain moisture as well. Perfect to deter slugs and snails as they resist crawling over the jagged edges of the straw and hay. Use around strawberries and other tender leafy plants like lettuce. It helps to keep the leaves of your tender plants off of the soil and therefore they are less prone to mold and sogginess. If you have used around annuals you can work into the soil to improve drainage and aeration as well. Cheap to get hold of at local farmers stores or even pet stores.
- Problems As A Mulch Heavy winds can take it and make the whole plot look untidy. We also have chickens and use hay in their bedding so it can genuinely encourage our girls to sit on our raised beds. Squashed strawberries all round!
- Great As A Mulch For once it has had a chance to break down. Around a year in a normal compost bin is usually enough. Mixed with all of the above named ingredients and more garden waste alongside egg shells, coffee grinds, tea bags and unprocessed meat free food scraps. We call it black gold but it works very well as a mulch once it has broken down a little, not quite enough to be soil to grow in. When spread over a top layer of your garden it can add nutrients and warmth. This is because it is still decomposing and releasing heat as it breaks down.
- Problems As A Mulch If it is too nitrogen rich it can kill off some fruit baring trees and care will be taken to look at each plant before spreading a thick layer. Monitor what goes into your compost bin carefully as some diseases will live on and are not biodegradable in that sense. This means you could be passing the disease on to your new planting area.
- Great As A Mulch For It will regulate heat and protect roots from frosts but also help the soil to retain moisture as well. Easy to come by and you can spread a nice thick layer. It will decompose and works well when added to soil for aeration and to aid drainage.
- Problems As A Mulch When the wind blows and your garden looks like it has been visited by a popcorn machine. Not great as it also harbors bugs and pests who will come back out of hiding in Spring to eat your garden.
Comfrey/ Borage & Green Manures
- Great As A Mulch For It will regulate heat and protect roots from frosts but also help the soil to retain moisture as well. It is going to add a big hit of nutrients to your soil as well. Used as a slow release feed it can help a plant all year round.
- Problems As A Mulch Leaves that are freshly dug through will be a great habitat for bugs, both the good kind and the kind who come out at night and eat all of your crops. Keep an eye on this and encourage natural predators as well. Also be aware that not all plants want or need a fertilizer. So if you know your plant would benefit from adequate soil conditions, maybe look at the alternatives.
- Great As A Mulch For It will regulate heat and protect roots from frosts but also help the soil to retain moisture as well. Slow release of nutrients and other beneficial micro organisms into your soil. Mix in with leaves and grass cuttings then put to one side for a few weeks for the perfect mulch for veggies or roses. We use chicken manure as our free rangers bedding gets added to the compost heap. This is another great way to incorporate animal manure.
- Problems As A Mulch Make sure that the manure is roughly a year or older. This is because some animals do not fully digest their food and it can mean you are introducing seeds to an area. Do not pile around tree or shrubs as the manure is still decomposing and it will potentially harm the bark.
Newspapers / Shredded Cardboard
- Great As A Mulch For those who want a quick fix. So cardboard is used in an almost upside down way as a mulch. Integral to the no dig method and used as a base for any raised bed. Then you add your well rotted manure as a growing medium to the top. It will suppress weeds and stop perennial roots becoming a problem.
- Problems As A Mulch Not ideal if you are growing plants that have a long tap root. These are basically vertical root systems as opposed to the more common horizontal root systems. So plants like Marsh Mallow or Borage would not thrive in a few inches of growing medium.
Wool / Fleece
- Great As A Mulch For .. Anywhere that you also want to look tidy. It will regulate heat and protect roots from frosts but also help the soil to retain moisture as well. Fleece is great for overwintering and is biodegradable but wont add much in terms of nutrients to your garden. It is more that it will help with aeration and aid drainage. It is also the ultimate in wildlife friendly products as the birds will steal some for their nests as well. We love watching them making off with little tufts in their beaks.
- Problems As A Mulch It can create a little micro system for bugs and pests to thrive in, some beneficial and some less so. Once you have removed your fleece in Spring, conduct a bit of a torchlight search for slugs and snails.
General Word Of Warning
Mulch is not the answer to all plants. Mediterranean herbs tend towards being drought tolerant and will thrive with dry and exposed base. This helps them to feel more at home in their settings. A mulch would mean a build up of moisture and could possibly start to rot the plant.
Some gardener’s use a water permeable sheet and then cut growing holes in. This can then be smartened up by adding wood chips or gravel to the top. We do not recommend this as you are holding problems for another year when the material eventually rips or is degraded. Then you will have real problems with weeds penetrating. I am saying this as someone who has inherited this issue and to make matters worse they didn’t even purchase water permeable so we get pools of water forming and the plants are dying of drought.
In pots colored glass pebbles or slate chippings can make very attractive layers that act as a form of mulch. Just be careful as dark colors and light colors can absorb or detract heat.
I have not included hops here as even though we grow our own hops, we compost the spent bines fully. This is because dogs are allergic to the leaves and we cannot promise that they won’t get hungry at some point!
What Next & Further Reading