When it comes to growing healthy, productive vegetables and flowers in raised beds – success all begins with filling your raised beds with the perfect mix of soil!
Raised beds are becoming more and more popular every year – and it’s easy to see why. Not only does gardening at a raised level make it easier to maintain your plants, elevated beds also have the advantage of having far less weeds to deal with.
But one thing is for sure, whether you are growing flowers, vegetables or herbs, the soil you put into your raised beds matters. To grow great plants it needs to be lightweight, full of nutrients – and also drain well. Which is exactly why how you fill them up matters!
The simple fact is, what you use to fill your beds – and how you fill them up will have a tremendous impact on how successful the plants you grow in them will be. Not just for the coming year, but for years to come.
With that in mind, here is a look at the best method for filling up your beds, and why simply loading them full of just plain soil is not good for your plants – or your raised beds life and longevity either.
Filling Raised Beds For Big Success
It’s important to think of raised beds just as you would a container or potted plant. This is because they both have limited soil capacity. To be successful, a potted plant needs to have great drainage as well as be loose and lightweight. In addition, it also needs to packed with nutrients.
That is exactly the same formula for success when growing in raised beds. The soil has to drain excess water away in quick fashion. If it doesn’t, plants will struggle to grow and can easily rot out in the soil.
Furthermore, if the soil is not loose and lightweight, the plants will have a hard time establishing roots. Heavier soil makes it hard for roots to expand. Even worse, it also makes it hard for them to absorb nutrients. Heavier soils also tend to have far less nutrients than lighter soils with added ingredients.
Last but not least, heavy soil can bow out, bend and even break the sides of raised beds. Especially if the beds are made from weak plastic, thin metal or wood.
What Soil To Avoid When Filling Raised Beds
To work effectively, raised beds need to have at least 12 to 18 inches of workable soil. If your beds sit on the ground, as long as the soil underneath is workable, the sides of your beds can be a bit smaller – but having at least 12 inches to grow in is a must. 18 inches is even better!
As for filling them, it’s a must to avoid using only basic topsoil or even soil from your garden. It’s not that you can’t use some regular soil in the process, but as you will see next, layering in organic materials and other soil boosters is the real key to growing success in raised beds.
So what about using potting soil? Although you could fill your beds entirely with a fertile, loose potting soil, not only would it be quite expensive, it also doesn’t help create the best drainage situation at the bottom of the bed. Potting soil alone tends to pack down tightly – especially when it large quantities.
Instead, it’s far better to fill the bottom 1/3rd of your bed with larger organic material. This will allow excess moisture to drain through easily. In addition, as the larger material breaks down over time, it adds even more humus and nutrients to the soil.
The Best Organic Materials To Use At The Bottom
One of the best materials to use for this are small logs, sticks and twigs. They can all often be found for free – and help fill your bed with excellent organic matter. Even better, they also provide great drainage at the bottom by keeping the soil from compacting down.
For larger, deeper beds, use large bark pieces, wood chunks and tree limbs to layer in the bottom 1/3rd. Don’t worry about stacking them neatly. In fact, tossing them randomly will create air channels that can help as the soil and other materials are added later.
For smaller and less deep beds, small sticks and twigs are best to fill the bottom 1/3rd. This will still allow enough soil depth for growing the first year. When selecting wood species, maple, pine, oak, beech, fruit trees and most non-nut trees are fine to use. Avoid nut trees such as walnut and chestnut as they can prohibit plant growth.
If you do not have access to wood scraps, you can substitute hardwood mulch for the bottom area. The larger the mulch the better. Finely shredded mulch will be heavy much like topsoil would be. It also will not provide good drainage.
Filling Your Raised Beds With Energy
Once the organic layer of sticks, wood and bark is in place, it’s time to add even more long-term power. This can be accomplished with a combination of materials. Compost, straw, grass clippings and even aged manure are all excellent for this layer.
If you only have access to one of two of these, that is more than fine. The real key is to add more organic material to this layer before putting in the final layer of soil.
This layer should make up another third of your total height. It’s important that this layer of organic material is small enough to work down in between the hardwood layer. Together, they will allow for incredible drainage as well as a long term source of nutrients for plants as they break down.
Adding The Soil
Now it’s finally time for the soil! For this layer, you need to be adding a lightweight, power-filled potting soil mix. Remember that your beds are in a confined space, so they need to have all of the energy possible right from the start.
There are many great potting soils that are available for purchase. The key when selecting a good potting mix is to make sure it is lightweight and filled with organic power. Look for potting soils that contain compost, perlite, worm castings and other organic powerhouses. Affiliate Product Link : Espoma Organic Raised Bed Mix – All Natural and Organic Potting Soil Mix
The good news is that by filling 2/3rds of your bed with organic material – and the other third with great potting soil – it can save big on the cost of adding a quality nutrient filled soil. But make no mistake, skimping on this step will severely impact your growing ability if it is a poor quality soil.
You can also create your own incredible potting soil mix by mixing compost, pulverized top soil, worm castings, perlite and coffee grounds. See our article: How To Make The Best Potting Soil Mix Around
Last but not least, never fill your beds completely to the top. Leave a few inches for mulch that can protect plants and help insulate the soil temperature.
Here is to filling your raised beds for success, and enjoying years of fruitful growing for years to come!
Simple Garden Life
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