Best Way to Fill Raised Garden Beds
A few weeks ago I built several raised garden beds, each of which cost me less than $50 a box to build. Now that they were all built and in place, reality hit and I knew I needed to fill them up if I actually wanted to have a garden this year!
So, I immediately went on a hunt for the best ways to fill raised garden bed without breaking the bank! But I also wanted to make sure I filled them with the best combination of materials to make sure we have a successful garden. I will have to report back on that second part as we just got everything planted.
So pull out some gardening gloves, grab a wheel barrel, and pretend worms and insects don’t live in any of this matter! Lastly! If you are like me and allergic to poison ivy, put on long clothes and get ready to sweat!
Layer One: Creating a Base and Weed Barrier
Okay, the last thing I want to do (or really have time to do!) is fight weeds throughout our garden! For the base layer I wanted to use something that would create a good weed barrier and hopefully limit the number of weeds that would pop up in between our fruit and vegetable plants.
There are a lot of products out there that you can purchase, such as a landscaping fabric which is designed to create a weed barrier.
However, for me I wanted to do this more cost efficiently! After some research, I settled on using cardboard and paper bags. Over a few weeks I just saved all my delivery box and paper grocery bags. So using these was FREE!
In addition to being a great option because carboard create a weed barrier and it is free; decomposing cardboard adds organic matter to the soil and will improve your garden’s drainage and boosting nutrient levels!
Layer Two: Bulk Filler - Wood Logs
If you have a deep bed, mine are 16 inches deep, you are going to want something that can take up some space! Could you imagine the cost if you were to fill up a 16 inch bed with all dirt!
Sticking with my goal to keep cost down while also creating a good base for our plants to grow, for my next layer I used wood logs. For me this was again free as we have had several trees fall on our property that my husband had chopped up to clear out of our yard or pathways through the woods.
If you have to purchase wood logs I would recommend searching on places like Craigslist or Facebook Marketplace. A lot of times you can find someone who had a tree go down and just want the wood cleared off their property. Otherwise you could search for local firewood sellers to purchase some logs to fill your beds.
Like the layer before, decomposing logs also provide nutrients to your beds. So initially, the logs provide you with a bulk filler but as they break down and decompose the wood releases water and nutrients into the soil and and the rotting logs will hold extra moisture to benefit your planting soil. Logs will also allow for good drainage in your beds.
Layer Three: Small Filler - Sticks and Brush
This layer can be relatively sparse as your next layer will do most of the fill in.
With all the larger log in place in the raised beds, I pick up some smaller sticks and brush that had accumulated over the winter months. I used this to fill in some of the larger gaps between the logs.
The benefits of using sticks and brush are the same as those for using wood logs.
Layer Four: More Filler - Leaves & Yard Waste
Leaves can be super beneficial in raised garden beds! Of course, the first benefit to you is this another free filler. For you garden, the leaves attract earthworms to the soil and as they decompose they create beneficial microbes.
Also, after moving all the logs and sticks and filling the beds this was such a nice light and fast filler for my beds!
Use the leaves to really fill in around the logs, sticks, and brush. Try to push the leaves down into the cracks and spaces.
If you do not have access to leaves and yard waste another cost efficient option for this layer would be to use straw bales. You can normally find straw bales for $3 – $6 each.
Layer Five: Top Soil - Soil & Compost Mix
This is your last layer and the layer you will plant your garden in! There are so many option for your top layer. For my 4′ x 8′ boxes I estimated that I need ~18 – 19 cu. ft. of soil.
First, you can just purchase raise garden bed soil – this sells for about $10 for 1.5 cu.ft. This is a premixed fertilizer soil blend. This is the most expensive option, costing $10 for only 1.5 cu.ft. At $180 per box this was not an option for me.
The next options is to buy a top soil and mix in a compost for fertilizer. A 1 cu.ft. bag of top soil is about $3/bag and 1.5 cu.ft. bag of compost is about $4 – $5/bag. This option will cost ~$8 per 3 cu.ft. This option would save me about $40 a box but was still a bit more than I wanted to spend.
The best option to get your top soil layer is to go to a local excavating or landscaping supply company. Generally these places will offer top soil and top soil mixes by the truck bed (1 ton). A 1 ton load equates to about 40 cubic feet. We found an excavating company that sold a top soil mix for $49 per ton. We got three loads to fill all our beds (four 4’x8′ beds and two 4’x4′ beds); so in total it cost us $29.40 to fill the large bed and $14.70 to fill the small beds! This was much more in the cost I was hoping to spend to fill our garden beds!
Things to Keep in Mind
- This was a labor intense process! Make sure you are prepared for the weight lifting and lots of walking and moving.
- The three layers of filler will decompose. Of course we want this to happen, but over time you will need to be prepared to add more soil to keep your boxes filled.
- Cost will vary depending on where you are located.
Best Way to Fill Raised Garden Beds
- Weed Barrier Landscaping Fabric or Cardboard
- Wood Logs
- Stick & Brush
- Composting Filler Leaves and Yard Waste or Straw
- Top Soil Mix Premixed soil, or top soil & compost
- Layer One: Creating a Base & Weed Barrier
- Layer Two: Bulk Filler - Wood Logs
- Layer Three: Small Filler - Sticks & Brush
- Layer Four: Leave & Yard Waste (or Straw Bales)
- Layer Five: Top Soil - Soil & Compost mix