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Aug 102012

Vegetable gardening systems fall into three major categories, 1) low-intensity victory gardens planted in wide rows or hills,  2) intensive gardening systems planted in beds, or 3) container gardens.

Victory Garden Designs

The victory garden is especially good for growing plants that are needed in large quantities, such as corn, peas, beans, potatoes, and broccoli. There are many adaptations to the single row planting design typical of the victory garden. Here are descriptions and pointers on managing common planting arrangements:

Garden row layoutRow Planting: This arrangement consists of long, straight rows, usually two or more feet apart, with a single line of plants growing down each row.

Broadcast Row Planting: Broadcast planting usually involves placing seed in rows arranged as wide bands rather than single-width rows. Many crops, especially root crops such as carrots, radishes, and beets will produce higher quality vegetables when planted this way

Hill Planting: Larger vegetables, such as melons, squash, corn, and cucumbers, may be planted in hills. The hills can be arranged as extra wide rows to facilitate cultivation with distance between hills based on recommendations for individual crops.

Intensive Garden Designs

Intensive garden designs require considerable effort to plan and install, but are thereafter relatively easy to maintain. Proven intensive garden designs include raised beds and vertical gardens. When combined with production techniques that include interplanting, succession planting, relay planting, and edible landscaping, these garden designs will help maximize the use of limited space.

Raised bedsRaised Beds: The typical design of the “raised bed” garden includes a defined border filled with heavily amended soil to a level above the surrounding ground. Typical beds are raised six to eight inches but they may be as much as three feet above grade. Borders may be made from concrete, masonry, or wood. Wood landscape timbers are commonly used for borders and should be made of redwood or cedar to minimize deterioration due to constant exposure to moisture. Although there is no evidence that the new generation of treated timbers is toxic or harmful to plants or consumers, it may be wise to exercise caution and use only untreated wood.

Soil preparation is an important aspect of raised beds. The final soil mix commonly consists of one part native soil and one part compost or aged organic matter. Many other choices for soil components exist and include manures, peat, sand, vermiculite, or perlite added in various quantities. The simplest method for preparing the soil is to remove the top 12 inches of soil from the completed bed, place it in a pile, mix the pile with an equal amount of organic matter, and shovel it back into the bed

Plant arrangement within a raised bed should optimize the use of the limited space. The goal is to space plants equidistant from each other on all sides, so that, at maturity, plant leaves touch or slightly overlap.. The use of dwarf or bush type varieties will help minimize space needed for producing many crops, such as beans, cucumbers, tomatoes, and squash.

To learn more about gardening in raised beds, see the Colorado State University publication: Block Style Layout in Raised Bed Vegetable Gardens.

Vertical gardeningVertical Gardening: The use of trellises, nets, strings, cages, or poles to hold plants upright and limit horizontal spread constitutes vertical gardening. Vining and sprawling plants, such as cucumbers, tomatoes, melons, and pole beans, are obvious candidates for this type of gardening.

Structures for supporting plants can take advantage of existing structures, such as buildings or fences, or can stand as an isolated structure. The height of the support apparatus will depend on the crop being grown. Shorter plants such as tomatoes, cucumbers, and pole beans will grow to a height five to six feet. Squash may need fifteen to twenty feet of vertical space or a structure that will allow some horizontal growth at the top such as a high tunnel

Vertical gardening saves considerable space but is labor-intensive. This is mostly due to the need for staking, tying, and pruning associated with the process of training new growth upward.

Container Gardens

A window sill, patio, balcony, or doorstep can provide sufficient space for a productive container garden. Gardening in containers requires more attention to detail than any other gardening method. The plants have only a small amount soil available for root growth, meaning limited water and nutrient availability. Also, the plants are subject to heat and other stresses. As a result, care requirements are more stringent and often unique in comparison with a traditional garden.

Choosing Containers: Containers can be made of clay, wood, plastic, or metal. Most importantly, they should be the proper size and provide good drainage.

Container gardenSelecting the proper container size is a balance between supplying adequate soil volume and making sure they can be moved in cases of inclement weather or for winter storage. Choose the largest containers you can feasibly manage. Container depth is important because most plants need at least 6 to 8 inches of soil for proper rooting.

Choosing Soil Media: The best soil media for container gardens are ironically are called ‘soilless mixes”. These contain combinations of peat moss, perlite, and sand. Some include wood chips or bark. Native garden soil alone does not make good potting soil because it does not provide adequate drainage or air exchange. Soilless mixes are sterile and contain few nutrients. Manufacturers usually add major plant nutrients to mixes they sell, but may not add trace elements that are necessary for good plant growth. This problem can be solved by using the soilless mix as a base and adding compost (about 25% by volume).

Placing the Containers: Position containers where plants will receive sun during the entirety of daytime hours. If this is not possible, choose crops that can withstand some shade. Generally leaf crops can tolerate some shade while vegetables grown for their roots or fruits need a minimum of 8 to 10 hours of full, direct sunlight each day. Available light can be concentrated somewhat by providing reflective materials around the plants (e.g., aluminum foil, white-painted surfaces, marble chips on the soil surface).

Choosing Vegetable Crops and Varieties for Containers: The best container crops are those that allow best use of the available space. This includes many herbs, carrots, radishes and lettuce, or crops that bear fruits over a period of time such as tomatoes, peppers, or cucumbers. Dwarf or miniature varieties of many crops are available.

Tips for Growing Vegetables in Containers: If you can move or protect your container garden from frost, plant two to three weeks earlier than you would an outside garden. Avoid planting too many plants in one container. If cages, stakes, or other supports are needed, install them just after planting or thinning to avoid root damage later.

Vegetables suitable for container gardening,
recommended pot size, and spacing between plants
Vegetable Minimum container size Spacing (in) between plants in containers*
Bean 2 gallon 2 to 3
Beet 1/2 gallon 2 to 3
Cabbage 5 gallon 1 plant
Carrot 1 gallon 2 to 3
Cucumber 5 gallon 1 plant
Eggplant 5 gallon 1 plant
Kale 5 gallon 10 to 15
Lettuce 1/2 gallon 4 to 6
Mustard greens 1/2 gallon 4 to 5
Onion 1/2 gallon 2 to 3
Pepper 2 gallon 8 to 12
Spinach 1 gallon 4 to 6
Squash 5 gallon 1 plant
Swiss chard 1/2 gallon 4 to 6
Tomato 5 gallon 1 plant
Turnip 3 gallon 2 to 3

*Any vegetables that produce large plants should have only one plant per container.

Water only when the plants and soil indicate a need. Check containers at least once a day to determine if the soil is damp (but not sopping wet) below a depth of about one inch and water if the soil feels dry.

There are some tricks to conserve water in containers:

  1. grouping containers together provides shades for the pots and slows evaporation;
  2. placing something impermeable, such as a plastic or rubber mat, under a pot prevents moisture from moving out of the pot and into cement or masonry surfaces;
  3. mulching and windbreaks can also help reduce water requirements for containers.

If plants are grown for longer than 8-10 weeks, add water-soluble fertilizer every 2 to 3 weeks. Use dry fertilizer (slow release), well-aged manure, or compost at the recommended rate (information provided on the product label).Inspect plants periodically for the presence of foliage-feeding and fruit-feeding insects as well as the occurrence of diseases. Treat as needed.

To learn more about container gardening, see the following publications:

Texas A&M University: Vegetable Gardening in Containers No.545
Ohio State University: Container Vegetable Gardening No. 1647
Iowa State University: Container Vegetable Gardening No. 870

 August 10, 2012