Growing Together: Grow vegetables in raised beds and containers

Don Kinzler
Forum News Service

The Victory Garden is back.

Even before the current pandemic skyrocketed interest in vegetable gardening, millennials were rediscovering the term “Victory Garden” and its concepts. Victory Gardens were national movements during both world wars, and home gardeners grew tremendous quantities of vegetables for themselves and to share.

Fresh vegetables in the backyard garden or stored in the freezer or root cellar helps us become self-sustaining. When finances are tight, a vegetable garden greatly reduces the grocery bill.

Last week we discussed traditional gardening in a plot of ground. What if you can’t dig up the lawn, or your space is limited, or you live in an apartment or condo?

Raised gardens and container gardening make it possible for almost everyone to grow vegetables.

Raised gardens

Kits are available online and from garden centers, or you can make a raised garden yourself. The structures can sit flat on the ground or lawn, without a bottom structure, or raised on legs with a bottom installed.

To construct your own, use cedar or brown treated lumber, both safe for garden use, with dimensions 2 inches thick by 12 inches wide. One-inch-thick boards can be used, but aren’t as strong. Don’t use older, green-treated lumber, which contains unsafe compounds.

Raised gardens are most commonly constructed 4 feet by 4 feet, which lets you reach the center easily from each side. For a larger garden, build several of the 4-by-4-foot units, or an 8-by-4-foot raised garden. Locate where they’ll receive at least six to eight hours of direct sunshine.

A highly recommended successful innovation in raised gardening is called square foot gardening, made popular by author Mel Bartholomew. Square foot gardening maximizes the raised garden, producing the greatest amount of vegetables in the space available, while giving each vegetable type just the right amount of space to flourish. Production is amazing.

Raised gardens grow best when filled with materials other than “dirt” type of soil, which packs tightly in these structures. Instead, a blended mix is recommended, such as one-third each of peat moss, compost and vermiculite. You can also buy bagged mixes labeled for raised or square foot gardens.

For square foot gardening, begin by making a grid across the 4-by-4-foot frame. Pound a nail, or even a push pin, into the top edge of the lumber at 1-foot intervals around the frame’s perimeter. From each nail, stretch a string or twine firmly across the frame from one side to the corresponding nail on the opposite side.

When completed, the strings divide the garden into 16 squares, each measuring 1 square foot. These squares establish how much of each vegetable is planted in that square foot.

Next, decide which vegetables you’d like. You can plant combinations in each raised garden frame. Theoretically, you could plant a different type of vegetable in each of the 16 squares, but you’ll likely want more than one square of vegetables you prefer.

How many seeds or transplants to plant in each square depends on the type and how much room they need to grow. For carrot and radish, plant 16 seeds per square. For beet, pea, lettuce and string bean, plant nine seeds per square. For bulb-type onions and Swiss chard, plant four per square. For broccoli, cauliflower, cabbage, Brussels sprouts, cucumber, pepper, squash and potato, plant one per square.

Tomato plants are suggested as one per square if grown in a cage, but I’ve found a single tomato plant might require up to 4 four squares, unless side shoots are pruned off as they grow.

Devote as many squares as you wish to vegetables you prefer. Use trellises or cages for vining crops like cucumber and squash so they grow upward instead of spreading outward.

After planting, the guide strings can be left in place until seeded crops emerge, and then removed if desired.

Container gardening

For patios, decks and apartment balconies, vegetables can be grown in containers. The same principles of raised bed gardening apply, since a raised bed is basically a large container. Locate in full sunshine.

Begin with a high-quality potting mix in containers at least 12 inches or greater in diameter and depth. For tomatoes, use a container at least the size of a 5-gallon bucket for best production.

To decide how many plants each container can hold, follow the guidelines above for square foot gardening. For example, a 12-inch-diameter container could hold 16 carrot plants, or nine beets, or one broccoli plant.

Containers dry out more quickly than raised gardens, so water thoroughly when the top inch dries. Smaller containers require more frequent watering. Fertilize with a water-soluble fertilizer every two weeks.

Fielding questions

Q: The branches on the shrub in the photo were bent and buried in snow after the wet and heavy snowstorm last fall. As you can see, it has split. What should I do, saw it off below the split? Should I also cut back the branches that spent most of the winter laying on the ground? — Julie Henderson.

A: I love a good mystery, and I wasn’t certain what type of shrub this was until I saw a few remnants of past arborvitae foliage, and a little sprig of arborvitae’s evergreen foliage in the photo’s corner. And the bark fits globe arborvitae.

Identification is the first step in knowing what to do, because deciduous (leafy) shrubs are handled differently than evergreen shrubs when damage happens. If the splitting and collapsed branches in the photo happened to a deciduous shrub, the remedy is straightforward and successful: prune the shrub all the way back to 6 inches above ground level, and it will regenerate nicely.

Evergreens, however, don’t have the same ability to sprout from bare lower branches. Pruning should be limited to cutting back to areas that still have healthy evergreen foliage.

If you’d like to see what happens, cut the split branch below the damage, and lightly trim the other branches, hoping the reduction in weight might encourage the other branches to return to position. I’m normally optimistic, but I believe a replacement might be the end result in this case.

Q: As the snow is receding, I’m noticing gray, cottony mold on the grass. Is it too early to start raking it off? — Linda M., Fargo.

A: Snow mold on lawns is most prevalent when snow arrives early in the fall and leaves late, which are the conditions of the past several years. Snow mold can be mitigated easily by gently fluffing up the matted, moldy grass with a leaf rake. The mold usually disappears with this aeration without permanent damage.

Rake lightly as soon as possible. Vigorous raking of lawns should wait until you can kneel on the grass without getting a wet spot on your jeans. Raking too early while the lawn is moist can damage grass shoots.

Q: I recently read an online post saying we should resist the urge to clean up flower gardens until temperatures are consistently warm, because many butterflies and bees are currently overwintering in the hollowed stems of last year’s plants and if we clean the gardens now, we are throwing away this year’s beneficial pollinators. Is this true? — Cindy Klapperich, Oakes, N.D.

A: Several of us here at North Dakota State University Extension collaborated on an answer, and yes, this is true.

Extension Entomologist Janet Knodel says you can still clean up gardens but instead of putting the stems into the trash, she puts them on a new compost pile and leaves them for a year or more before starting the composting process of decomposition.

Extension Horticulturist Esther McGinnis likewise recommends waiting to cut down perennials until you start seeing native pollinators active in spring. Concern for pollinator nesting coincides well with our past recommendations to leave the tops of perennial flowers intact over winter, instead of clear-cutting in fall.

In the past, the main reason for delaying cleanup until spring was because perennials tend to survive winter better if tops are left on. Now we realize that the hollow stems of perennials are also important for winter survival of pollinating bees and butterflies.

When is the safe time to clean up the perennial bed in spring? The old tops generally need to be removed before new growth emerges from the base.

To save pollinators that might be nesting, remove the tops when needed, but instead of disposing of them, leave them in the vicinity. Most of us have areas around or to the rear of a perennial bed where a layer of perennial tops could be laid on the ground in a small pile and left until midsummer.

Raised beds can produce quantities of vegetables where a traditional garden isn’t possible.
A reader wonders what they can do to help this split shrub.