This post may contain affiliate links. If you make a purchase through links on our site, we may earn a commission.
One of the major benefits of gardening in a raised bed is you get to control the soil that goes into it. This is especially advantageous for gardeners with a property that has hard-packed or clay soil, issues with tree roots, or concerns about pollutants. It also comes in handy if you want to place your raised bed on a patio or driveway. Since good soil is the foundation of a healthy garden, you want to make sure you’re setting your vegetables up for success. So, what is the best soil for a raised garden bed? In this article, I’m going to share some advice on figuring out how much soil you need, what to purchase, amending a soil delivery, and more.
Another raised bed benefit is that the soil will remain friable. In an in-ground garden, the soil can become hard-packed over time as you walk between the rows. We know there is a whole web of micro-activity happening in our soil, so it’s best not to disturb it. A raised bed allows you to reach in to weed and plant.
How much soil do you need?
Filling a raised bed will likely require more soil than you think. A soil delivery might make the most sense economically. For my gardens, I’ve put a tarp out on the driveway and had soil delivered in a giant pile that my husband and I work at diminishing over time with multiple wheelbarrow trips. There are some great soil calculators online that can help you figure out the amount you need so you don’t over or under order. Anytime I’ve ordered a bit too much, I’ve added the soil to my other garden beds.
Another option I’ve taken advantage of is a bulk soil delivery in one big bag. This is much better than purchasing multiple small bags of soil. I have simply marked where I want the soil to be delivered and a forklift has deposited it in place. This option is a bit less messy than a traditional soil delivery. The soil is covered and protected from the elements, and there when you need it.
How to save a bit of money on soil
There are some ways to fill in the bottom of a raised bed so you don’t need as much soil to fill it. For example, if you happened to cut out the sod underneath where your raised bed will go, flip the pieces, grass-side-down to fill the bottom. There is lots of soil attached and the grass will break down over time—especially after you cover it in fresh soil. You could also add yard waste, like leaves from a compost pile or big branches and sticks.
Another option is if you’ve moved soil around to create a garden, you can use that for the bottom, provided you amend the soil on top accordingly.
The best soil for a raised garden bed
When I built my raised beds, I called around and ordered what I thought would be a good-quality triple mix. In Ontario where I live, triple mix is generally top soil, compost, and peat moss or black loam. A 50/50 mix seems to be more common in the U.S., which is a blend of top soil and compost.
If you’re ordering a soil delivery, try to find out where your soil has come from. Topsoil is often taken from land being developed for new subdivisions. It might have sat for a long time and can be devoid of nutrients. Make sure what you’re getting is a blend that will nourish your plants.
If you’re purchasing bags of soil, look for labels like organic vegetable and herb mix or organic garden soil for vegetables and flowers.
Whatever soil you end up using, you want to make sure you amend it with compost. All that rich organic matter is an important component that will hold moisture and provide nutrients to your plants. Compost is an essential ingredient in the best soil for a raised garden bed, no matter which mix of ingredients you choose.
I filled my beds with about 3/4 triple mix, and even though it had compost in it, I top-dressed the garden with about ¼ compost. If you don’t have a compost pile, there are all sorts different types of compost on the market. Garden centers sell everything from mushroom or shrimp compost, to composted manure or bags labelled “organic vegetable compost.” Your municipality might even have free compost giveaway days in the spring.
Amending the soil in your raised bed
If you don’t have a compost pile, keep some compost on reserve throughout the gardening season. If you’re pulling out your spent pea plants mid-summer, for example, not only are you removing a bit of earth, but those plants will have depleted the soil of nutrients. Topping up your beds with compost will add nutrients back into the soil to prepare it for whatever you plant next.
I like to add chopped leaves into the soil in the fall. Run them over with your lawnmower and sprinkle them into your beds to break down over the winter. I have a compost pile where all the other leaves go. When they’re ready, I’ll use the leaf mold to spread in my gardens. To maintain the health of even the best soil for a raised garden bed, adding organic matter every year is essential.
In the springtime, I also will amend the soil with compost and/or composted manure. I find the soil levels in my raised beds are usually lower from the weight of the snow. A spring refresh fills them back up to the top, adding lots of fresh nutrients into the raised bed.
Additional soil advice
- Discover the various organic garden soil amendments you can add to your raised bed.
- It’s a good idea to do a soil pH test from time to time, so you can make the necessary amendments that will help your crops to flourish.
- If you have smaller containers to fill, check out Jessica’s recipes in her DIY potting soil article.
- Learn the difference between potting soil and garden soil.
- Growing cover crops is also a great way to add nutrients back into the soil.
- If you are growing berries, like strawberries and blueberries, which like a more acidic soil, you can purchase soil that’s been specially formulated to grow them, or adjust the level with elemental sulfur or aluminum sulfate.
Tips for building and planting raised beds
For more information about starting a raised bed project, check out my book Raised Bed Revolution, and my course, Raised Bed Basics for Savvy Gardening School. Both cover the importance of choosing good-quality soil, as well as lots of other advice.
You have to be careful with compost. It’s easy to think it’s a fix all wonder amendment. My local landfill sells compost made from grass clippings & leaves.. I added it the first year and the next year. I then had a soil test and my P&K levels were off the charts high! I only used nitrogen for the next several years because there was still enough P&K. I use cow manure compost now, once every 2 years. I get it from our university. About 2″ in my raised beds. Take it easy with compost! Raised bed and potting soil is a better bet for replenishing the lost soil in raised beds.
Hi Stacy, That’s a great point!
After years of in-ground veggie gardens I’m on to two standing raised beds approx 12” x 8′ x 2′. Not knowing better I loaded them with Espoma Organic Garden Soil and now see that it is not meant to be used that way by the stunted under-nourished seedlings. (I tried adding nitrogen but no change). Any suggestions to get me through this growing season and also what I should do for next growing season when the beds are empty? I’m ready to pull the seedlings, re-do the soil composition, and re-plant. Thanks so much!
Hi Martha, Was the garden soil meant for growing vegetables in containers? You may want to add some compost to the mix. In any container of mine that needs to be refilled, I use organic soil formulated for growing vegetables. I would leave the soil you have in there for next year and top-dress it with compost and more of the aforementioned vegetable potting soil. The other thing is, do your standing raised beds have good drainage?
Hi Tara,
I bought a large fabric garden bed from Amazon and want some advice on filling it on a budget. Any tips.
Hi Pamela, If it is deep, I’ve used some of the cheap bags of black earth that are usually just used to make a garden look aesthetically pleasing and are about $2/bag. If you’ve dug up grass, you can turn the sod over and use that to fill the bottom, as well. Then make sure all the good stuff is in the top layers where the plants will grow.
Hi. Last year we bought raised beds on legs and tried to grow veggies. For media we used compost and dirt. It didn’t go very well. When we watered it seemed to drain too quick. My wife thinks maybe the seeds were not so good.
This year we’re trying compost and Miracle Grow for veggies. Any other ideas? We live in the Detroit Michigan area
If your raised bed drains quickly I would recommend really giving it a good soak when you water. I would also recommend looking for container mixes formulated for vegetables. Often they’ll contain something that helps to retain the water. I bought an organic bag of ProMix on the weekend for some of my big pots.