Many gardeners prefer raised garden beds over traditional in-ground gardens because they provide numerous advantages. They provide better drainage, soil quality, and allow for easier access to plants. However, before you start planting, it's essential to prepare the foundation of your raised garden bed.
In this blog post, we'll take a closer look at what should be placed at the base of a raised garden bed and why it's so important.
Why is the Base of a Raised Garden Bed Important?
The foundation of your raised garden bed is crucial for the health and productivity of your plants. Without a solid base, your garden bed could suffer from several issues, such as poor drainage, erosion, or soil compaction. This can lead to root rot, disease, and a decrease in plant growth.
Therefore, it's essential to create a strong, stable, and well-draining base for your raised garden bed. The materials you use will depend on the location, size, and design of your garden bed.
What Materials Can Be Used at the Base of a Raised Garden Bed?
1. Gravel or Rocks: A layer of gravel or rocks can provide excellent drainage for your raised garden bed. This will prevent water from sitting at the bottom of your garden bed, which can lead to root rot and other issues. Gravel or rocks can also help prevent erosion and soil compaction.
2. Landscape Fabric: A layer of landscape fabric can help prevent weeds from growing up into your raised garden bed. This is especially important if you're building your garden bed on top of grass or other vegetation. Landscape fabric will also help to prevent soil from washing away or becoming compacted.
3. Sand: A layer of sand can help improve drainage and prevent soil compaction. However, it's important to use the right type of sand. Avoid using beach sand, as it can contain salt and other minerals that can harm your plants. Instead, use horticultural sand, which is specially designed for gardening.
4. Compost: Adding a layer of compost to the bottom of your raised garden bed can help improve soil quality and provide nutrients for your plants. This is especially important if you're building your garden bed on top of poor-quality soil.
5. Cardboard: A layer of cardboard can help suppress weeds and prevent soil from washing away. It will also break down over time, providing additional organic matter for your plants.
6. Soil: If you're building your raised garden bed on top of poor-quality soil, you may want to add a layer of topsoil or other high-quality soil to the bottom. This will help improve soil quality and provide a good growing environment for your plants.
A strong and stable base is essential for the health and productivity of your raised garden bed. By using the right materials, such as gravel, landscape fabric, sand, compost, cardboard, or soil, you can create a well-draining and nutrient-rich foundation for your plants. Take the time to prepare the base of your garden bed correctly, and you'll be rewarded with a bountiful and healthy harvest.
FAQs
Cardboard or newspaper: Cardboard is a great option if you are on a budget. You can line the bottom of your raised garden bed with cardboard and newspaper to deter pests and weeds.
What should I put at the bottom of my raised garden bed? ›
Depending on your budget and gardening goals, you can line the bottom of your raised garden beds with wide-mesh hardware cloth, stainless steel mesh, landscape fabric, burlap sack, or newspaper/cardboard.
Should I put sand at the bottom of my raised bed? ›
Avoid using beach sand, as it can contain salt and other minerals that can harm your plants. Instead, use horticultural sand, which is specially designed for gardening. 4. Compost: Adding a layer of compost to the bottom of your raised garden bed can help improve soil quality and provide nutrients for your plants.
Should I put cardboard in the bottom of my raised bed? ›
It acts as a physical barrier to block out pernicious weeds. Usually, 2 – 3 layers of cardboard will suffice, though you may want layers in more weed-prone areas. The damp environment created by the cardboard is conducive to earthworms and other beneficial soil microorganisms.
Should I put landscape fabric under a raised bed? ›
Promotes water retention: For looser soils that cannot hold water well, adding landscape fabric as a liner helps retain moisture for longer. Although made from permeable material, the fabric delays the water flow because it's an added layer. Water doesn't gush out of the raised bed as quickly.
What are three mistakes to avoid when gardening with raised beds? ›
Seven Beginner Raised Bed Gardening Mistakes to Avoid
- Picking The Wrong Spot.
- Not Thinking About The Water Source.
- Raised Beds Placed Too Close Together.
Should a raised bed have a bottom? Despite lining the bottom of a raised bed, the raised bed itself should not have an enclosed bottom. Raised garden beds should be left open to the ground to allow plant roots to grow further into the ground for nutrients if needed.
What is the foundation for a raised bed? ›
Lay a concrete foundation 150mm deep using 1 part cement to 2½ parts sand, 3½ parts gravel. Lay three courses of bricks, two bricks wide, in the centre of the trench. The mortar mix is 1 part cement to 3 parts sand. You have now reached ground level.
Should you put rocks in the bottom of a raised bed? ›
Rocks are not essential for achieving proper drainage and can even hinder it. Limited soil depth. Placing rocks at the bottom of a garden bed reduces the available soil depth for plant roots to grow.
What is the best liner for raised beds? ›
You can line your raised bed to make it more durable and to prevent toxics from leaching into the soil. For lining, use landscape fabric found at garden supply stores or cloth fabric from clothing. Avoid non-porous plastic, as it can retain too much water and discourage beneficial insects and worms.
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.
Do you need to put anything under a raised garden bed? ›
If the raised garden bed is being placed in an area of bare ground with no weeds, grass or sod then you can put the raised garden bed frame directly on the ground. Or for a little added protection at no cost, add a layer of cardboard or newspaper underneath.
What to fill the bottom of a raised garden bed with? ›
Save Money by Adding Leaves to the Bottom of a Raised Garden Bed. Leaves can be super beneficial to a garden. They fill your beds with organic matter that will slowly build great soil, and they're free!
How deep should a raised bed be? ›
A raised bed does not need to be very deep to be effective, but the surface underneath your garden bed affects which depth is right. In general, eight inches is a good minimum depth for raised garden beds.
What is the best surface for a raised bed? ›
Timber is the most popular material for constructing raised beds and is very versatile. Pressure-treated softwood sleepers are an attractive and economical alternative to hardwoods like oak, and will last for many years.
How to fill a raised garden bed cheaply? ›
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).
What should you line raised beds with? ›
You can line your raised bed to make it more durable and to prevent toxics from leaching into the soil. For lining, use landscape fabric found at garden supply stores or cloth fabric from clothing. Avoid non-porous plastic, as it can retain too much water and discourage beneficial insects and worms.
What not to fill a raised garden bed with? ›
I've seen suggestions online to add plastic bottles or trash bags as filler to the bottom of raised beds to save money on soil. This not only defeats the purpose of installing a raised bed in order to give your plants' roots all the growing room they need, it also can negatively impact the drainage of your raised beds.
What do you put in the bottom of a planter for drainage? ›
One of the best things to put at the bottom of a planter for drainage is broken pieces of pot. You can use any unwanted plant pots or chipped crockery for this – simply smash them up into small to medium-sized pieces. Adding a layer of broken pieces of pot like this will prevent compost loss out of the drainage holes.
