Raised bed gardening is a fantastic way to grow herbs, vegetables, and flowers. Even though most of us don't grow our entire year's supply, contributing to our well-being by growing some of what we eat provides a connection to the land and a deeper appreciation for our food. Besides, it's fun!
For many people, raised bed gardening is the best fit due to reasons such as poor soil, drainage issues, small space, or even health. Especially for those limited in space, raised beds offer the possibility of higher yields in a given area. If you're wondering about the orientation or direction in which raised beds should be built for maximum yield, we'll provide some answers, as well as other considerations.
It's All About The Sun (mostly)
We all know as gardeners that sunlight is the energy driver for photosynthesis. Without adequate light, plant growth suffers. Light is the critical factor that allows plants to rearrange carbon dioxide and water into sugar molecules—plant food. Less light for the plant equals less plant food. Less plant food means smaller plants, fewer blooms, or less fruit.
Plants have different survival strategies, including how much light they need to survive, based on their natural habitat. A fern doesn't need much sunshine to thrive, but a birch tree does. Tomatoes, for example, need a lot of sun. Lettuce is a low-growing leafy plant that can make do with partial sun and does its best in the cooler temperatures of spring and fall when other plants are less likely to shade it out.
You’ll see these sun strategies on a seed packet or in the plant description, identifying if the plants need full sun, partial sun (also called partial shade), or shade. Most of our garden veggies want full sun, although some, like lettuce, will be fine with partial sun.
For most situations, exposure to sunlight is maximized when raised beds have a north-south orientation (the long side of a rectangular bed runs north to south). Since most of us plant following the long side of the bed, this will result in rows running north to south—if you are that orderly—and maximizing light for each plant. However, many other factors play a role in the amount of light a plant gets and where a raised bed should be located.
Since raised beds are more or less permanent once installed—if they are built with side walls and not just raised mounds of soil—siting them correctly is an important task. Moving the frames and yards of soil to relocate them isn’t an easy job. Spend some time exploring your potential site, and look for these factors to get the most out of your raised beds.
Placement for Sunlight
Unless you live near the equator, the sun's path in the sky changes with the seasons, and of course, what areas of your yard are in the sun or shade varies throughout the day. In the northern hemisphere, the sun will be at its highest point in the sky on the summer solstice, around June 21st.
Before and after that day, it will appear lower in the sky, changing which trees and buildings provide shade and for how far. The shed that appears to cast too much shade in your backyard in January may not be a problem by May when planting time rolls around.
While it sounds obvious, don't forget deciduous trees will cast more shade in the summer. It’s easy to overlook that simple fact when planning garden beds before the leaves are out in spring.
Drawing a map of your yard and sketching in the shadows from trees and buildings can help identify problem areas—areas without sufficient sun to grow a good crop of vegetables. Anticipate where the sunny areas will be in spring, summer, and early fall. You'll want to create this sun map for several different times of the day, morning, midday, and afternoon.
Tall Plants Cast Shade Too
In the same way that a tree or garage can cast shade, so can tall garden plants. Plan to grow crops like sunflowers, corn, or trellised beans on the north side of the garden bed in most situations. However, you can also use that shade to your advantage. Some crops do best in cooler weather and will bolt or quit under late summer's hot rays. Succession plantings of cool weather spring crops like kale or peas can take advantage of the growing shade provided by midsummer corn or pole beans, extending your harvest.
Vertical growing is a popular way to expand the production of a raised bed and provide a visually appealing upright structure. Cattle panel arches, trellises, and bean tripods are excellent ways to get vertical and show off some of the cucumbers, squash, or other vining crops you're growing, while also conserving space. If you're inspired to let your garden reach for the sky, consider the shading effect that vertical vegetation may cause on your beds and plan accordingly.
Wind Protection
We often don't consider the wind when planning a garden space, especially when finding a sunny spot. Strong winds can cause problems for garden plants like tomatoes, pole beans, or other tall crops. Even bushy varieties don't like to get blown around. While a bit of air circulation is a good thing to keep fungal disease down, too much wind can break stems, tip over your corn, or flop tall flowers.
Wind often gets channeled between buildings, like a garage and a house, creating an artificially higher wind speed. If you live in an area with frequent high winds or storms, consider using wind protection from fences, hedges, or buildings when choosing a site for raised beds.
Watering Considerations
You found a sunny spot out of the wind where you can build your new raised bed gardens. Great! Now, is there access to water? Running a hose across the driveway may not be ideal. Your raised beds will drain more quickly than in-ground gardens and will likely need supplemental watering in the summer heat. Easy access to the water source will make that more enjoyable.
While the beds will drain more quickly than a traditional garden, you'll still want to avoid placing them on ground that frequently ponds after a rain.
Not every yard has the perfect combination of factors for raised beds, but that's okay! Choose the best of what you have. As long as there is adequate sunshine, at least 4–6 hours per day, you can grow a veggie garden. Even sun-loving plants like tomatoes or potatoes will still produce when grown in less than full sunshine—they'll just fruit a little less.
If the space you have doesn't make sense for a north-south layout, that's okay, too. Planting strategies using the south side of the beds for shorter crops and the northern side for taller crops can help mitigate layout issues. Beds don't have to be perfectly aligned with the compass, either.
These same ideas can and should be applied to your container gardens. While the north-south layout isn't a big deal for a round pot, a sunny (or shady depending on the plants) location out of the wind and ease of watering are still factors for happy and successful gardening.
If your new raised beds will be in the yard, consider if you'll be mowing around and between them. Don't space them 18 inches apart if your mower is 21 inches wide. While maximizing use of a tight space is important, leave yourself room to access the beds from all sides.
All else being equal, beds aligned north to south will have the most even sunshine and the best production. However, drainage, ease of access, and wind are important factors when locating beds. Ultimately, the most important factor is creating a raised bed and enjoying it, whether or not the perfect site is achieved.
Read more on plants and light levels, why your lettuce bolts, and more in our Gardener’s Greenroom.
