Getting as many veggies into a raised bed—throughout the short Midwest growing season—is a quest for many gardeners. What goes where, when and why when stuffing raise beds with vegetables and herbs?
I set out to learn the best method of getting the most out of my two 4 foot by 8 foot wooden raised vegetable beds, and in my research I learned about companion, intercropping and succession planting. All of these ideas provide tricks to plant as many crops as possible that will grow from March through early winter. In talking to so many gardeners over the years, I know that you can cram a lot into a small raised bed. In the past I have planted herbs among my tomatoes to help keep down the weeds. But the real feat is creating a plan, getting the right timing of the crops and using effective trellising.
Therein lies the challenge: knowing what vegetables and herbs to plant, when, where and how.
Intercropping can be defined as planting fast-growing vegetables amidst slower-growing plants. It can also mean two compatible plants growing along side each other.
Companion planting is the art of planting vegetables that work together, either as insect deterrents, nitrogen fixators (such as beans), flavor enhancers or supports.
Successive planting can be defined as planting the same crop at different times to produce a supply throughout the season.
“The main idea for intensive vegetable beds is that plants should intermingle, you don’t want to plant in rows,” explains Tim Pollak, outdoor floriculturist at the Chicago Botanic Garden in Glencoe, Ill. “It should look like a patchwork quilt when it’s growing, with all of the spaces filled. Secondly, you’ll want to take advantage of the air space and sunshine above the beds—use trellises, poles or nearby fences to go upward.”
The second most important step to a productive, intensely planted raised bed, Pollak says, is to properly prepare the soil in early March. Till or spade in an amount of compost no more than one-quarter of the depth of the bed—for instance, 3 inches of compost in a bed that is 1 foot deep. Also add slow-release fertilizer according to package directions.
Pollak also notes that a little wintertime research on companion planting and succession planting will pay off later on. “Decide which vegetables you want to grow. Make a list. It might be mainly tomatoes or greens, or maybe you want a little of everything, including herbs. Then research their needs, timing, requirements and companions,” he says. “Whole books have been written on this subject. Plus, what works for one gardener might not work in your garden due to sunlight, soil or other microclimate factors.”
For example, there are good companions, such as anything from the mint family and tomatoes, and there are bad companions, such as fennel with a lot of different veggies, he notes. In addition, many herbs are very useful in an interplanting scheme. Basil and tomatoes are popular bedfellows.
Once you have chosen your desired vegetables, decide which vegetables can go vertical. Vining types of cucumbers, pole beans, squash, eggplant, tomatoes and peas can all climb up trellises, poles or even suspended netting. These vining plants take advantage of the unused vertical space, as well as add visual interest. A wall of blooming beans is pretty. Vertical plants, however, cast shadows—be aware of the shade patterns and site the trellises and poles accordingly. For example, in the summer a bit of shade might be good for lettuce, which is a cool-season crop, but bad for peppers, which need full sun.
Some plants, such as carrots, lettuce, mustards and greens, can be “relay planted” throughout the entire season, Pollak suggests. “You plant these every few weeks for successive crops. Tuck them into the planting where space allows.”
Michael Walkup, owner of Walkup Heritage Farms and Gardens in Crystal Lake, Ill., starts the season with beds of peas, radishes, beets, kale, arugula, spinach and chard. Then in the summer, his beds are changed over to the warm-season crops, including okra and beans. One of his favorite warm-weather threesomes is tomatoes, basil and parsley. “They all grow wonderfully together, and they enhance each other’s’ flavors,” he notes. “I also plant herb wormwood (Artimesia absinthium) around the perimeter of the bed to discourage insects.”
In late summer, Walkup starts his plants indoors for his fall vegetable beds, which he religiously plants on Labor Day. He raises kale, Brussels sprouts and cabbage as well as lettuce.
Like Walkup’s date with the garden on Labor Day, remember that timing is everything when it comes to intensive raised bed planting. Pollak says, “Make sure you stay on your planned course, even if things in the bed are still growing. You may need to generalize or make specific unbreakable appointments to keep the planting schedule on track. For instance, you might say, ‘On August 1 I am going to plant my fall greens,’ even though you might have to pull some of the green beans that are still going strong.”
And as you progress through your first year of intensely planted veggie beds, Pollak suggests keeping notes. “Write it all down so you’ll know what worked and what didn’t.”
As the snow flies, sit down with your vegetable books and seed catalogs and plan to cram.
If You Build It
Most experts recommend building boxed raised beds no wider than 4 feet—for example 4-by-8 ft. or 4-by-4 ft.--so that you can reach into the middle of the bed from both sides. Vegetable beds also need full sun, and the best soil you can obtain.