Raised Beds and Container Gardens

We all know how much kids love sandboxes. They can spend hours digging, sifting, pouring, and building as they create and recreate dynamic mini-environments. Within this small and defined space, children immerse themselves while nurturing their senses and imagination.

Raised beds and container gardens take the attraction of sandboxes to a whole new level. They offer an added quality of complexity and variation as children create microfarms to observe, cultivate, and reap the resulting harvest throughout the seasons.

What are Raised Beds and Container Gardens?

Raised beds and container gardens are above the ground in a defined space full of rich, healthy soil in which plants can thrive. While container gardens are enclosed in receptacles — which can be anything from a child’s outgrown wagon to an old bathtub — raised beds may or may not have sides. Sometimes raised beds are merely mounds of soil sitting on top of the original soil, and they can take many shapes. Others are framed by borders of wood, stone, or other rigid material and are often rectangular or square. Container gardens and raised beds are ideal for turning areas that appear unsuitable for gardening — such as narrow corridors, busy courtyards and playgrounds, and school building rooftops — into abundant and attractive spaces for children to experience gardening. These types of gardens can be custom-built or made from a kit and can be sized and shaped to fit the needs of the site and people who will use them. They are also relatively easy to take care of and can be both beautiful and bountiful.

Advantages

Works on Any Surface - You can create a lovely garden in an area where the soil or subsurface is not amenable to gardening, such as asphalt, concrete, compacted clay, rock, or where there is heavy-metal contamination.

Surface-Friendly - Wherever you have 4–6 hours of direct sunlight on most days, you can place a productive and inspirational garden, no matter how small the space.

Easily Accessible to All - Raised beds and containers are accessible to people of all ages and physical conditions. They can easily be wheelchair accessible.

A Good Size for Kids - They provide a manageable area for children to cultivate.

Won’t Get Stepped On - Raised beds prevent people from walking in the garden, which is beneficial when young children and large groups of students visit.

Controls the Pests - It’s easier to keep pests such as snails, slugs, gophers, or birds out of raised beds and containers.

Opportunity to Recycle - Container gardens in particular can be made from a variety of discarded and repurposed items, keeping them out of the landfill.

Year-Round Usage - If you live where there are cold winters, you can convert a raised bed into a cold frame or low-tunnel type garden for four-season production.

Mobile - Container gardens can easily be mounted onto casters or wheels and made into mobile gardens for bringing into classrooms and demonstrating how gardens grow with differing amounts of light.

Disadvantages

Needs Frequent Irrigation - The soil in a raised bed or container can dry out quickly and may need to be irrigated more frequently than in a traditional garden.

Can Be Expensive - While container gardens can be made out of a whole range of materials, enclosed raised beds can be expensive to build. If you are buying lumber or bricks for one large bed or many beds, the costs add up quickly.

More Difficult to Maintain - An unenclosed raised bed is easier to establish but may be more difficult to maintain in the long run. It is more vulnerable to people, animals, and wind that can disturb its borders. Even if you buy bagged soil that claims it’s nutritious, the only way to build and maintain healthy soil is by mulching, amending the soil with minerals and compost, and growing cover crops.

Possible Flooding - Raised beds and containers drain directly onto the surface on which they are placed, which can lead to flooding and a muddy mess. If your garden will be on an asphalt or concrete surface, make sure the beds and containers are near a drain or are uphill from an area that can absorb the runoff.

Isolated Environment - Enclosed raised beds and container gardens are a somewhat controlled environment within a physical boundary that separates them from the surrounding natural world, making it difficult for children to experience the myriad of complex interconnections among plants, animals, and the landscape.

Space Is Limited - They may not be large enough to engage more than a few kids at the same time.

Designing the Garden

1. Choosing a Location

• Before you settle on a place to develop your garden, take the children to visit potential sites at different times of day. Have them keep a record of their observations.

• The area will need at least 4–6 hours of sunlight on most days.

• Note if the area is windy at times and, if so, the direction that the wind tends to blow.

• Check whether buildings or trees shade some or all of the space. If the garden is next to a building, note the direction it is facing.

• Ask kids to observe the animals that visit the space and determine if any of them are “residents” that stay all year.

• Make sure there is a source of water nearby.

• Identify what will have to be removed if you convert this space to a garden.

• Brainstorm other elements you would like to include in the garden, such as a toolshed, a compost bin, a propagation area, or chickens or other farm animals.

• Determine the ideal size of your container garden or raised bed. Do you and the kids plan to create more than one, either now or in the future? If so, is there room to expand?

• Should there be walking paths or enough space for kids to push a wheelbarrow between the raised beds or containers?

• Will all sides of the container or bed be accessible? Will children be able to reach to at least the middle of the bed from one or more sides?

• How will people travel to, from, and around your container or bed? Is it easily accessible, yet not a barrier to traffic flow?

2. Selecting Materials

Container Garden

• When choosing a container, select something that has the potential to be attractive and is made to last for many years, such as an old enameled bathtub or sink or a repurposed galvanized animal-watering trough. You and the children can brainstorm ideas and choose from your list.

• If you plan to cultivate a variety of plants, your container or bed should be at least 3 feet deep so you can grow plants with moderate root extension. The deeper your container, the more options you have. Keep in mind that the children will want to help construct the garden, so choose a design that will allow for them to be involved. (See sidebar “Children and Tools” in this chapter.) And, of course, make sure the material is safe for children and other living things, with no sharp edges, protruding nails or splinters, or rust.

• Make sure that you can move the container when it’s empty. Using a wagon or some other container on wheels is an innovative solution to that problem.

• Wine or whiskey barrels, cut in half, are some of the best containers for gardening. They are a recycled material, a good size for children to work in, and are made out of oak, which is a long-lasting hardwood.

• Make sure there is a way to allow water — but not soil — to drain out of the container.

Raised Bed

• Raised beds can be made from many different materials, including wood, broken concrete (“urbanite”), brick, stone, or recycled plastic lumber. Think about what is accessible, attractive, economical, and easy to work with.

• Raised beds are most often made out of redwood because it is resistant to rot. However, unless the redwood has been salvaged from another structure, it is not considered a renewable resource, so consider using something else.

• Other woods, such as pine and fir, come from forests that renew quickly. Therefore, they are considered to be more renewable than redwood. They are also often less expensive. Unfortunately, they break down faster than other building materials and must be replaced within 5–10 years, depending on the climate.

• Pressure-treated wood, including railroad ties, should be avoided even if free of arsenic, because it contains harsh chemicals.

3. Selecting Soil

• For container gardens and raised beds, it is easiest to use an organic soil mix from a nursery, local topsoil, or a combination of the two.

• Regardless of the source, mix in some compost or apply an organic fertilizer that is appropriate for the types of plants you plan to grow. If the soil is dense, add some sand or rice hulls to improve drainage.

• Kids love to pour water through jars of soil and compare the rates at which they drain. This is a way to involve students in selecting the best soil for their garden.

4. Choosing Plants for the Garden

• Do you plan to grow food in your garden, or perhaps flowers to attract hummingbirds, or create a mini-garden of plants that are native to your area? Regardless of what kind of garden you want to create, the plants that will grow successfully are determined by the size of your container or raised bed.

• Also, remember that some plants have deep root systems and may not have enough room to expand downward in their search for water and nutrients. If your container is at least 1½–2 feet deep, you can grow vegetables like radishes, lettuce greens, and herbs. If your container is at least 2–5 feet deep, you can add beans, cucumbers, and peas. If you want to include tomatoes, asparagus, pumpkins, or other plants with deep root systems, your container or bed should be at least 3 feet deep.

• Younger kids will enjoy tasting various fruits and vegetables that grow well in your area and deciding which ones they want to grow. Older students can research various plants to determine their space requirements and practice their measuring skills to determine which plants have the potential to thrive.

5. Maintaining a Raised Bed or Container Garden

Maintaining your container garden or raised bed is similar to maintaining any garden. Just remember, you and your kids will need to add nutrients and water more frequently than with a traditional, in-the-ground garden, because the nutrients leach out as the soil drains and the water dries up more rapidly. Compost is an ideal source of nutrients and can be periodically mixed in with the first few inches of topsoil. Depending on the type of plants, you can also use fish emulsion, powdered eggshells, or organic powdered fertilizers. Kids enjoy vermicomposting, so consider setting up a worm bin. (See “Composting” sidebar in this chapter.)

Checklist of Materials for Container Garden or Raised Bed

You will need at least one of these:

• A receptacle to convert into a container garden that will allow water to drain

• A large box or other structure that will hold an enclosed raised bed and will allow soil to drain. To build one, you will need:

  • Recycled lumber, urbanite, bricks, or other material to frame the bed

  • Electric saw

  • Drill and drill bit to make drainage holes Gopher wire

  • Corner supports

  • Tools to construct the enclosed raised bed

For either type of garden you will need:

• Nutrient-rich soil that drains well

• Drainage rocks (especially important in a container)

• Water

• A system for getting water from a faucet to the garden container or bed

• Compost or other substances that replenish the nutrients in soil

• Plants selected for the space of your container and your geographic region

• Simple gardening tools, such as gardening gloves, trowels, a hand weeder, a watering can, a hose, a hose nozzle, and a wheelbarrow or wagon