Raised beds can start to get tired and lose the productivity they once had. But worry not; there are plenty of ways to revitalise your raised beds.
Many of these methods are completely free but require some forward planning. So even if your beds aren’t yet screaming for help, it can be a good idea to start planning.
Compost
Adding a layer of compost to the top of your raised beds is a great way to add lots of nutrients back into depleted soil.
I personally add a layer to all of my beds every year. only a couple of centimetres deep.
This layer serves a dual purpose. It both adds soil life and nutrition to the bed and acts as a mulch to suppress weeds.
You can use shop-bought compost for this, but it will soon get expensive.
For that reason, I like to use my homemade compost. You can have a pile ready for next year if you start now. Even lazy composting works well when given enough time.
If you don’t want to get into the nitty gritty of compost science, then just chuck all your dead plant material in a big pile, give it a turn in 6 months and then by 12 months, it will be useable compost.
Leaf Mould
Leaf mould is a great free resource. When done correctly, it can be a fantastic material to spread on top of your tired raised beds to pump them back into shape.
But what is leaf mould exactly?
As the name suggests, it is made from leaves, ones that have rotted down well.
This forms a very light, loamy soil packed with nutrients. What’s more, you just need to collect leaves in the autumn, pile them together, and then wait.
I like to use a wire mesh box that I built to keep my leaves in. This allows for plenty of airflow which helps to stop the leaves from sticking into one big clump (a common problem).
Another really easy way is to collect your leaves into black bin bags. Punch a few holes in the bags and then store them out of sight somewhere.
Come back to the bags in a year or two, and they will be full of gardeners’ gold!
Rotted Manure
Manure is the allotment holder’s favourite. Usually made from horse waste, manure is packed full of nitrogen and is the original fertiliser.
Scatter some over your raised bed to boost everything growing in it. Also, as an added benefit, worms love it, so you will be increasing their number in your soil too, a win-win.
Ensure the manure is well-rotted, i.e. it has been decomposing in a pile for a year already. You don’t want fresh manure.
Fresh manure will be so packed full of nitrogen that it will be a detriment to your raised bed. It can lead to nitrogen burn in your plants, among other issues.
It also tends to clump together and form an impenetrable mat.
Biochar
Biochar is simpler than it sounds. It is essentially some plant material that has been burned and turned into ash.
This could be wood ash from a fire, but it also gets a lot more complicated than that. Commercial biochar is often made from rice husks, a by-product of rice production.
True biochar is made by burning the material with a lack of oxygen. This creates a very absorbent material that is great for heavy soils and is loved by soil microbes.
While this may sound complex, it is an ancient process that was heavily used in the Amazon rainforest. This process helped create a wonder soil that is still there today and more fertile than any modern-day soil.
The original amazonians achieved this, we believe, by layering all of their food waste onto the soil. This included fish bones and animal carcasses as well as veg scraps.
This would then be burned but never allowed to take off, instead kept at more of a smoulder.
This created the low oxygen burn that creates “true biochar”.
Food Scraps
Another really simple way to improve your raised beds is to bury some food scraps under the surface of your beds.
This will quickly break down in the soil and release lots of nutrients back into it.
Just make sure you don’t include any animal products or breads, these can attract rats. Stick to fruit and veg, and you will be fine.