When I first bought a piece of property to build a house several years ago, a must-have was a designated spot for a vegetable garden. My parents and grandparents had a big one where I grew up, so having one myself was a ritual of our summertime lifestyle. Besides, I had just taken the position as the new horticulture Extension agent, and I had to have and know how to grow a garden. What would the neighbors or my clients think if I didn’t?
So, I picked out a sunny spot that had recently been cleared; got me a little tiller, and away I went preparing the soil to plant. Come spring, I followed my own Extension advice and planted the right varieties at the right time. I was proud of my accomplishment. What a harvest we were going to have. Paw Paw would have said, ‘Good job, son.’
The spring garden was planted, and we waited. Some seeds sprouted, and things started coming up. The tomato transplants looked good. The waiting continued. Nothing grew. More waiting. Still, nothing really grew. Weeks passed, and the garden was not doing so well.
Mayday! Houston, we have a problem.
Come to find out, the new area designated as my vegetable garden had bad soil. Actually, it was dirt – heavy, red clay that held water and would not drain well. My tomatoes were alive but would not grow higher than 24 inches. Most of the plants suffered from poor root growth. There I was, a horticulturist, and I couldn’t even grow a tomato plant.
Something had to be done if we were going to have a successful vegetable garden. Even if it was just to save my reputation.
I tell this story to get to the solution of what is my very successful vegetable garden today: raised bed gardening. Many people struggle with poor soil, rocky ground, lack of time or even lack of equipment. The best solution for that might be to grow home vegetables in raised beds.
Raised bed gardening is quite popular and is a convenient and easy way to produce homegrown vegetables. Unlike traditional in-ground gardening where lots of space is usually required, raised bed gardening is a perfect alternative for people that cannot garden due to limited garden space, poor or rocky soil, inadequate soil drainage or physical limitations.
The idea of raised bed gardening is nothing new. Many farmers and gardeners have mounded up soil to grow plants for centuries. This form of gardening is unique in that the soil level is raised above the surrounding soil – from 6 inches up to waist high – and enclosed with frame materials to prevent soil from spilling out. The contained soil is formed into 3- to 4-foot wide planting beds, small enough to be maintained without gardeners actually stepping onto and disturbing the planting area.
Raised bed gardens offer several advantages and some disadvantages over conventional garden plots.
■ Raised bed gardens can help maximize available space and are typically smaller than traditional gardens, making them a more convenient option in areas with limited space.
■ Higher soil levels and improved soil quality provides a means for better access, less maintenance and easier harvest.
■ They can be utilized as solutions for areas with poor and rocky soil or sloped terrains.
■ Beds are usually filled with high-quality soil mixes that have large amounts of organic matter, which improves drainage and may increase yields.
■ Soil raised above ground level tends to drain better and warms up much quicker in the spring, allowing for faster seed germination and transplant growth.
■ Dense planting techniques result in higher production per square foot of garden and help reduce weed seed germination.
■ Raised bed gardens can be entered and maintained soon after rain or irrigation without compacting soil.
■ No expensive power cultivation equipment is needed.
■ The formal orderliness and arrangement of a raised bed garden can be extremely attractive and a prized addition to the home landscape.
■ Elevated beds tend to dry out more quickly in the hot summer months, increasing the need for supplemental watering. Mulching helps maintain moisture.
■ Frame and soil materials for establishing a raised bed are an added expense.
■ Limited rotation of crop families may lead to increased soil borne disease pressure and nematode problems.
■ Increased plant density may increase some pest concerns, especially foliar diseases.
■ They are not well suited to sprawling vegetables, such as watermelons and cucumbers.
Raised beds could be made just from mounded soil, but these require a lot of maintenance. Most gardeners prefer to use some sort of framing materials to contain the new soil. Old railroad ties, landscape timbers, wooden board planks, rocks, concrete blocks or decorative bricks are commonly used for constructing raised beds. If wood products are used, they should be treated with wood preservative to increase life of the structures.
The size of a raised bed depends on the gardener. Frames ranging from 4 feet by 4 feet to 4 feet by 12 feet are ideal. The 4-foot width is preferred because it allows for an easy reach from either side without stepping into the bed, keeping soil compaction to a minimum. Length of the bed can also vary depending on type of construction materials used and the space available. A soil depth of 10 inches to 12 inches is desirable, as this will allow for improved drainage and adequate root development to produce healthy plants.
With raised bed gardening, do not use the native soil since the heavy red clay is typically the problem. That would just be putting the problem in a nice box. Gardeners must get new and better soil. There are numerous growing media options available when creating a raised bed. Any combination of purchased topsoil, compost, fine pine bark mulch or soil conditioner and/or peat will do well for growing vegetables in a raised bed.
Many places offer growing media by the truckload that can be very inexpensive. Commercially pre-packaged growing mixes that contain such items also are available and popular, but they are much more expensive than buying in bulk. There is no research to prove soil mixes by the bag are better and grow bigger plants compared to buying basic soil mixes in bulk. Do invest in a good soil mix since the correct soil media is the most important element of having a prosperous raised bed garden.
Lastly, growing vegetables in raised beds is different, so the gardener must re-learn many aspects of planting techniques. Gone are the long, straight rows with wide spaces in between. Raised bed gardens use all space to more efficiently maximize production.
Block planting is used with proper spacing between plants to optimize yields. More plants per square foot means more production and ultimately a larger harvest.
If you run into trouble like I did on my first go-around – or just want to grow a few veggies in a smaller space – try raised bed gardening. For a publication and more guidelines on raised bed gardening, visit www.aces.edu.
~ Shane Harris is the Tallapoosa County Extension Coordinator for the Alabama Cooperative Extension.