How to Build a Raised Bed | Garden Topsoil Direct (2024)

FAQs

How to Build a Raised Bed | Garden Topsoil Direct? ›

Use good quality topsoil such as a mixture enriched with fertiliser and compost. Make sure to compact the soil with a spade as you fill up. Add the soil so it's level with the top of the frame. The soil will eventually drop as it settles.

Smaller raised beds can be filled with bags of topsoil purchased from DIY stores or garden centres. If possible, you should check the topsoil before you buy to ensure it doesn't contain any stones, fibrous roots, weeds or even contaminants such as glass or bricks.

Add a mixture of compost and purchased topsoil in a 1:2 or 1:1 ratio, to the top of the bed. There are vendors who sell topsoil mixed with compost. Alternatively, fill the bed with compost and a soilless growing mix in a 1:1 ratio.

For a 4x8-foot raised bed with a 6” height, using Mel's Mix: about 5 cubic feet each of compost, peat moss, and vermiculite is needed. It usually takes about two to three bags of purchased fertile mix (1.5 cubic feet each) to cover the bed surface to a depth of 2 inches.

For best results, there should be another 12″ or more of good soil below the bed. This gives your plants at least 18 – 20″ of soil. (The soil in raised beds is usually a few inches below the rim of the bed. This is because soil compresses after several waterings.

It's best to use it wherever you're lacking soil, for example, to fill in a low spot in your lawn, or as a base layer in a new garden that's missing a foundation of soil. If you use topsoil in a garden, you'd still have to add additional compost or manure to help your plants thrive.

If you are gardening, you will want to avoid thicker topsoils that retain water very well – it's true that all plants need water, but thicker topsoils will not allow for much air to reach the roots of the plant. Topsoils with a loamy texture are great for gardening because they are easy to till and promote airflow.

Use the Lasagna Garden Method

To start, lay down sheets of cardboard or newspaper for weed suppression and then fill the raised bed structure halfway up with alternating layers of nitrogen-rich materials (like kitchen scraps and grass clippings) and carbon-rich materials (like wood chips and dried autumn leaves).

Layer the bottom with cardboard or newspaper as a weed barrier, which will decompose over time. Then, use a mix of yard waste, leaves, grass clippings, and kitchen scraps layered with soil and compost.

Add in fertilizer: The best soil for raised beds contains nutrients that promote growth. Raised bed soil is nutrient rich and contains a higher percentage of organic material than garden soil. However, you should also add additional organic fertilizer throughout the growing season to ensure a productive harvest.

How often do you change soil in raised beds? ›

Ideally, we think it's best to consider replenishing the soil between each season i.e. after every Autumn/Winter and Spring/Summer harvest; however, if you can only do it once a year, that's alright too.

To fill a 3x6 bed with 10" sides, you will need 15 cubic feet of blended soil. To create the blend, use the following quantities: 9 cubic feet of topsoil (9 20-quart bags) 4.5 cubic feet of compost (4.5 20-quart bags)

Each 4'x8' bed will require 1 cubic yards of soil.

Can I fill new raised beds with topsoil? No, topsoil on its own does not provide an adequate environment for plants to thrive. For best results, in addition to topsoil, other organic matter and soil amendments should be added such as compost and/or composted manure. Are all garden soils the same?

Plant tomatoes deeply because they can form roots along the stems. Therefore, choose a bed at least 12 inches deep and dig a deep planting hole. The more roots will form along the length of the stem; the easier it will be for tomatoes to absorb moisture from the soil.

Tomato plants should have about 18 inches between them so the roots will have plenty of room to sprawl out. In a 4'x4' raised bed, putting one plant in each corner should allow plenty of space for four plants with plenty of growing space. Plant tomatoes deep as they form additional roots along the stem.

Loamy Soil: The gold standard for most gardeners, loamy soil has a balanced mix of sand, silt, and clay. It retains moisture while ensuring good drainage and is rich in nutrients and organic matter.

What is Garden Soil? Garden soil is topsoil that has been enriched to make it better suited for plant growth. Amendments may include compost or other organic matter, and some soils – like perennial potting mixes – have added ingredients to encourage growth of specific types of plants.

The best way to amend soil in an existing garden is by top-dressing the bed with an inch or two of compost each season. The compost will break down, improving the soil structure and fertility. Plus, you'll perk up your perennials.

So if the soil in your garden is very shallow, or you are making new garden beds, adding or replacing a lawn, or putting in raised beds and need to add new soil, top soil is what you need.