Nicole's Take: Before you buy a single board or order a single kit, there are three decisions that will determine whether your raised beds set you up for years of success or leave you wishing you'd done things differently — what you want to grow, how much space you have, and which material will last in your climate and budget.

By Nicole Johnsey Burke: Founder of Gardenary and Author of Kitchen Garden Revival

Why Raised Beds Are the Foundation of Every Successful Kitchen Garden

There are two types of gardeners in this world: those who believe that growing in raised garden beds is the number one key to their success and those who believe that raised beds are a big ol' waste of money.

I might have fallen in the second camp if my first in-ground gardening experience hadn't been such a disaster. Switching to growing the majority of my fruits and vegetables in raised beds was a real gardening game-changer for me. After seeing the same results for the better with so many of my Rooted Garden clients and my Gardenary students, I've come to consider raised garden beds to be absolutely essential to the kitchen garden.

Before setting up your own raised bed, it's important to consider:

• What you want to grow - This will determine the depth and dimensions of your bed.
• Naturalness — choose materials as close to their natural state as possible: untreated wood, food-safe steel, stone, brick; avoid chemically treated materials that could leach into your soil
• Durability — factor in your climate, rainfall, and temperature range; the most beautiful bed is worthless if it rots or warps in two seasons
• Beauty — choose a material that ties into your home's existing style; your garden should feel like an extension of your landscape, not an afterthought
• Sustainability — research how your material was produced; Nicole prioritizes locally sourced materials and companies that replant what they harvest
• Affordability — the most durable options cost more upfront but save money over time by not needing replacement

Raised beds have both a practical and an aesthetic purpose. Let's look at the practical purpose first.

The Practical Case for Raised Beds

Raised beds are more practical when it comes to the soil quality, soil temperature, drainage, and ease of tending components of your kitchen garden.

Raised beds allow you to start with the best soil for growing veggies

First and foremost, raised beds allow you to start completely fresh with the soil in your kitchen garden, meaning you don't have to worry about weeds popping up or face challenges with your existing soil. It's like a fresh coat of paint on the walls in your living room or brand-new hardwood floors.

Many of the veggies we grow in the kitchen garden are picky about their soil. You could spend years amending your native soil if you're gardening in ground before those plants will be happy.

Raised beds regulate the soil temperature

Raised beds stay warmer than the soil in the ground. That's important when it comes to extending your growing time—think, planting earlier in the spring and continuing later into the fall or even winter. When I lived in Chicago, I could plant in my raised beds months before I could even think about working the soil of my in-ground pollinator garden.

Raised beds provide good drainage

Raised beds drain more quickly than in-ground beds. Most edible plants hate having their roots stay wet. In-ground plants are more likely to sit in water for longer than plants in a raised bed structure because the soil allows for faster draining, even when there's heavy rain.

Raised beds add to ease of tending

I don't know if you've tried gardening directly in the ground, but it can be hard and dirty work. My pollinator garden is in the ground, and I find it so much more difficult to tend those plants and work the soil there than in my raised beds. Almost all of my plants in my raised beds are level with my knees or my hands, so I don't have to do a lot of bending and reaching. Comfort and ease are important factors to keep you coming out to tend and enjoy your garden regularly.

Raised beds are also much easier for children to tend without stepping on things or falling over obstacles. For older gardeners, raised beds can save your knees and your back.

Those are the main practical reasons for having raised bed gardens.

The Aesthetic Case for Raised Beds

Even without plants, raised beds are a beautiful fixture in your landscape in their own right. I can see my raised beds and beautiful arch trellises even in the middle of the winter, when my in-ground pollinator garden is buried under snow.

Lots of people think they need to hide their vegetable garden away because it will look unsightly and messy. Raised beds keep the garden space looking tidy and attractive. In a raised bed, the wilder the plant growth, the more charming the space.

Now let's explore the three key things to consider before settling on the design and building your raised beds. These considerations are designed to help you make good decisions now—before you even gather your material—so that you can enjoy your gardening space to the fullest.

Nicole's Three-Decision Framework for Building Raised Beds

After designing 300+ kitchen gardens, I've found that every raised bed decision comes down to three questions asked in this exact order:

1. Depth first — What do you want to grow? Your plant list determines your minimum bed height. Get this wrong and your plants will underperform no matter how beautiful your beds look.

2. Footprint second — How much space do you have? Your available area determines your width and length. Measure before you buy anything.

3. Material last — What will last in your climate and budget? Only after you know what you're building should you choose what to build it from.

Most gardeners make the mistake of starting with material — they fall in love with a cedar kit or a Corten steel bed and order it before they've thought through depth or size. Start with the plants. Everything else follows.

Decision 1: What Do You Want to Grow?

When it comes to building a garden that will accommodate the type of plants you want to grow (and eat), the depth will be of extreme importance. Basically, the answer to this question will help you determine the best height for your raised bed.

The minimum height for a raised bed is six inches, and the maximum we typically do is about two feet.

Let's look at some of the types of plants you want to grow and which standard raised bed height gives them plenty of room for strong root formation.

Herbs and small leafy greens

If herbs and things like lettuce, spinach, and arugula are your priority, you really only need a raised bed that's 6 inches tall. These plants have small, shallow root structures. While you'll be a limited with what you can comfortably grow, you could always add some larger containers to the space for growing your favorite deeper-rooted plants.

Root crops and larger leafy greens

If you want to grow plants with deeper roots like carrots, celery, Swiss chard, and kale, it's best to double your materials and install a raised bed that's 12 inches tall. You can also grow smaller fruiting plants like beans and peppers. One foot is a pretty standard height for raised beds.

Larger fruiting plants

You need at least 18 inches to give plants like tomatoes and eggplants plenty of room to spread their roots down deep. With this height, of course, you can also grow herbs, leafy greens, and root crops quite comfortably.

While few kitchen garden plants need a full 24 inches of depth, I prefer raised beds that are just a little bit taller than what's required. I think 2 feet of building materials looks really stunning and also makes a big difference while tending your plants.

Raised Bed Depth by Plant Type:

• 6 inches — herbs and small leafy greens (lettuce, spinach, arugula, basil, thyme, oregano)
• 12 inches — root crops and larger leafy greens (carrots, kale, Swiss chard, chard, beans, peppers)
• 18 inches — large fruiting plants (tomatoes, eggplant, cucumbers, squash)
• 24 inches — Nicole's preference for any bed she's building; the extra height makes tending easier and the visual presence is significantly more beautiful

Decision 2: What Size Fits Your Space?

Unlike the height of your raised-bed garden, the ideal size can be limited by the outdoor space you have available. If you're still selecting the best location for your raised beds, read over our tips to pick the perfect spot. Then, measure the length and width of that area to determine what size of beds you can fit.

Here's the ideal width and length for building a raised bed.

What is the best width for a raised bed?

It's not really worth having a raised bed if you can't have one that's at least one and a half feet wide. Otherwise, you'll barely be able to fit any plants. (Don't worry though. You'll still be able to grow all the herbs and salad greens you could want in containers if you don't have room for a raised bed.)

The maximum width you would want for a raised bed is about four feet wide, and that would only be for beds that you're able to access from all surrounding sides. On average, our arms can only reach a little over two feet or so, meaning we can stand on one side of the bed and reach two feet inside, then move to the other side and reach two feet inside (unless you're Mrs. Incredible and can stretch your arms like elastic or something). If your bed is more than five feet wide, you'll have a hard time getting to the plants in the center without needing to step into the bed.

If you're planting against a wall or a fence and won't have access from one side of the bed, you want to have a more narrow bed. I'd say two feet wide max.

What is the best length for a raised bed?

There's definitely a sweet spot for raised bed length, and I'd say it's between 4 and 10 feet long.

If your beds are too long, the sides might start to bow. We've found that the best length for a bed maxes out around 10 to 12 feet long. I've installed beds as long as 25 feet, but we encountered issues with holding the bed structure together as all that soil was added. I recommend placing several raised beds side by side with a little 2-foot aisle in between them if you have a really long space.

If you're building raised beds out of wood, keep in mind that 8-foot-long boards are generally the most economic option. Many of the raised beds we design for clients are 8 feet long for this very reason.

Those are your general parameters for raised bed size.

Decision 3: What Material Should You Use?

There are many different options to choose from when selecting your raised bed material, so focus on these five characteristics to help guide your decision when selecting a raised bed material: naturalness, durability, beauty, sustainability, and affordability.

At Gardenary, we offer two materials we stand behind completely: untreated kiln-dried cedar and Corten steel. Both are food-safe, beautiful, and built to last decades.

Naturalness

You should select materials that are as close to those that occur in nature as possible: untreated wood, food-safe steel, stone, brick, or concrete. Avoid any chemicals used to treat your material that could then leach into your soil (and therefore into the food you're going to eat).

Durability

You're going to be putting a lot of time and money into this kitchen garden, so you definitely want to choose materials that will last as long as possible in your space, given your temperature ranges, humidity, and water intake that your bed will experience. If you're going with wood, here are ways to ensure your beds last longer.

Beauty

Ideally, choose a raised bed material that will tie into the rest of your home and landscape. Try to align the design decisions with your home's existing style and structure so that your garden will become an extension of what's already there, not an eyesore.

Sustainability

Do a little research to find out how your materials got to the lumber store or how the steel was created or where the stone was quarried. We prioritize materials that are locally produced when possible and companies that promise to renew their resources. If they're cutting down cedar trees, then they should be replanting cedar trees at the same time.

Affordability

You don't want to break the bank here. As you look through the different materials available to you, you'll have to determine which one best fits your budget.

Read more about the best materials for your raised beds.

Not only are raised beds more practical, but they add another layer of beauty as you step into your kitchen garden day after day. I'm confident that you're going to love having raised beds if you choose to install them in your outdoor space.

Going from an in-ground garden to a raised bed is like the difference between night and day. That's what I've found, that's what all of my Rooted Garden clients have said, and that's even what my mother confessed to me after she gardened in-ground for years. We gave her a raised-bed kitchen garden for Mother's Day a couple years ago, and she's been singing its praise ever since.

Keep these three considerations in mind as you're setting up your kitchen garden, and you'll love your raised beds as much as we do.

For more information on how to fill your raised beds with the best soil and plants, grab a copy of my book Kitchen Garden Revival, search our business directory for a garden coach near you, or enroll in Kitchen Garden Academy to learn how to be a successful kitchen gardener.

Happy growing!