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Aug 13, 2023

How to build a cost

I’ve wanted to grow a small herb garden for the past couple of years, but I just

I’ve wanted to grow a small herb garden for the past couple of years, but I just couldn't work out the right spot for it. The perfect location would be sunny, with nutrient-rich soil and able to contain members of the mint family, which can spread rapidly and overtake gardening spaces. It finally dawned on me that a raised bed herb garden might be the answer.

Raised bed gardens have many benefits and can provide opportunities for gardeners that lack ideal growing conditions for herbs, vegetables and even flowers. They can solve drainage problems in yards with heavy clay or sandy soils. They are the solution to nutrient deficiency problems in yards with infertile soil. They provide a safe alternative in areas with contaminated soil. They can be built on top of the pavement, in vacant lots and in other urban spaces. Hand tools are all that's required to maintain a raised bed. They can be built to a size and scale that fits your lifestyle. They are more accessible for individuals with limited mobility. Some raised beds are built to waist height to make gardening from a seated position possible. They can even make it easier to contain prolific growers like spearmint, lemon balm, basil, oregano, rosemary, thyme and parsley.

Building your own raised bed garden can be relatively inexpensive or it can get pricey. The key to building a cost-effective raised bed garden is figuring out how much space you need in advance and maximizing the use of the soil you’ll have to buy to fill it.

Determining how much space you need starts with adding up the mature sizes of the plants you want to grow.

For example, most mature herbs require about 1-4 square feet of space to grow to maturity. Basil, cilantro, mint, lemon balm and lavender are on the larger size, requiring 4 square feet of space. Thyme and parsley are on the smaller side requiring just 1 square foot of space.

Herbs are also nice because maturity can be a little more subjective. Mint leaves that are harvested when the plant is smaller are generally sweeter. You could likely get away with planting eight different types of herbs in a 4×2-foot raised bed if you stuck with smaller varieties and harvested them before full maturity.

Many garden vegetables are not as flexible with space. One mature tomato or pepper plant will take up about 4 square feet of space. In a 4×8-foot raised bed, you’ll be able to grow about eight tomato and pepper plants with a row of root vegetables or leafy greens in the middle.

Like herbs, root vegetables and leafy greens require less space and it's up to the gardener to determine the ideal time to harvest them. Additionally, the growing season is long enough for these cold hardy vegetables to plant a spring crop and a fall crop.

Large raised beds are more expensive because they require more soil to fill them up. However, with the same amount of lumber and fewer screws, you can double the amount of space you have for plants. And if you try the hugelkultur gardening technique, you can cut the cost of your initial soil investment.

With two 2x8x12 treated boards, you can build two 4×2-foot raised beds or one 4×8-foot raised bed. If you decide to construct two smaller beds, you’ll have 16 square feet of growing space. If you decide to build just one large raised bed, you’ll have 32 square feet of gardening space. In the same scenario, the two smaller beds will require 10 cubic feet of gardening soil and the larger bed will require 21 cubic feet of gardening soil.

The larger bed has the benefit of being able to grow twice as many plants without requiring any additional hardware and using half as many screws as the two smaller beds. However, you’ll need to spend twice as much on garden soil to fill it up, and your investment in fertilizer and organic matter will be greater over time.

In order to save money, you need to first determine the space you need and then maximize your materials. Although the larger bed in the scenario above costs more, you’re able to double the size of your garden and it's the better value long-term. However, if you’re never going to grow enough plants to fill it up, the smaller is the more cost-effective option.

Materials for two 4×2-foot raised beds

Materials for a 4×8-foot raised bed

Tools

Directions

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