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Vegetable Garden

  MG Manual Reference
Ch. 10, pp. 39 - 46

The purpose of an intensively grown garden is to harvest the most produce possible from a given space. More traditional gardens consist of long, single rows of vegetables spaced widely apart. Much of the garden area is taken by the space between the rows. An intensive garden reduces wasted space to a minimum. The practice of intensive gardening is not just for those with limited garden space; rather, an intensive garden concentrates work efforts to create an ideal plant environment, giving better yields with less labor.
Though its benefits are many, the intensive garden may not be for everyone. Some people enjoy the sight of long, straight rows in their gardens. Others prefer machine cultivation to hand weeding; though there is often less weeding to do in intensive plantings because of fewer pathways and closely spaced plants, the weeding that must be done is usually done by hand or with hand tools. Still other gardeners like to get their gardens planted in a very short period of time and have harvests come in all at once. The intensive ideal is to have something growing in every part of the garden at all times during the growing season.
A good intensive garden requires early, thorough planning to make the best use of time and space in the garden. Interrelationships of plants must be considered before planting, including nutrient needs, shade tolerance, above- and below-ground growth patterns, and preferred growing season. Using the techniques described below, anyone can develop a high-yielding intensive garden.
The raised bed
The raised bed Top
The raised bed or growing bed is the basic unit of an intensive garden. A system of beds allows the gardener to concentrate soil preparation in small areas, resulting in effective use of soil amendments and creating an ideal environment for vegetable growth. Raised beds warm-up more quickly in the spring. This is a major advantage when growing vegetables in the spring, giving them a head start. Because raised beds warm up faster and to a higher temperature by mid summer they dry out more quickly. In the hottest parts of Arizona raised beds may become too hot and use very high amounts of water. In the hot regions, gardeners should consider using lowered beds. With lowered beds, soil improvements are made below the natural grade rather than above and below but the other principles discussed are the same as for raised beds.
Beds are generally 3 to 4 feet wide and as long as desired. The gardener works from either side of the bed, reducing the incidence of compaction caused by walking on the soil.
Soil preparation is the key to successful intensive gardening. To grow so close together, plants must have adequate nutrients and water. Providing extra synthetic fertilizers and irrigation will help, but there is no substitute for deep, fertile soil high in organic matter. Humus-rich soil will hold extra nutrients, and existing elements that are "locked up" in the soil are released by the actions of earthworms, microorganisms and acids present in a life-filled soil, making them available for plant use.
If your soil is not deep, double-dig the beds for best results. Remove the top 12 inches of soil from the bed. Insert a spade or spading fork into the next 10 to 12 inches of soil and wiggle the handle back and forth to break up compacted layers. Do this every 6 to 8 inches in the bed. Mix the top soil with a generous amount of compost or manure, and return the mixture to the bed. It should be somewhat fluffy and may be raised slightly. To create a true raised bed, take topsoil from the neighboring pathways and mix it in as well.
This is a lot of work! Try it in one or two beds for some of your most valuable plants; if you like the results you can proceed to other beds as you have time. One nice thing about raised bed gardening is that it breaks work into units. Instead of gazing desperately at a garden full of weeds, thinking you'll never have time to clean it up, you can look at each bed and say, "I can do that in half an hour today!" Other chores are accomplished with the same ease.
By their nature, raised beds are a form of wide-bed gardening, a technique by which seeds and transplants are planted in wide bands of several rows or broadcast in a wide strip. In general, the goal is to space plants at equal distances from each other on all sides, such that leaves will touch at maturity. This saves space, and the close plantings reduce moisture loss from surrounding soil.

Vertical gardening Top
The use of trellises, nets, strings, cages, or poles to support growing plants constitutes vertical gardening. This technique is especially suited, but not limited, to gardeners with a small garden space. Vining and sprawling plants, such as cucumbers, tomatoes, melons, and pole beans are obvious candidates for this type of gardening. Some plants entwine themselves onto the support, while others may need to be tied. Remember that a vertical planting will cast a shadow, so beware of shading sun-loving crops, or take advantage of the shade by planting shade-tolerant crops near the vertical ones. Plants grown vertically take up much less space on the ground, and though the yield per plant may be (but is not always) less, the yield per square foot of garden space is much greater. Because vertically growing plants are more exposed, they dry out faster and may need to be watered more frequently than if they were allowed to spread over the ground. This fast drying is also an advantage to those plants susceptible to fungus diseases. A higher rate of fertilization may be needed, and soil should be deep and well-drained to allow roots to extend vertically rather than compete with others at a shallow level.
Interplanting Top
Growing two or more types of vegetables in the same place at the same time is known as interplanting. Proper planning is essential to obtain high production and increased quality of the crops planted. This technique has been practiced for thousands of years, but is just now gaining widespread support in this country. To successfully plan an interplanted garden the following factors must be taken into account for each plant: length of the plant's growth period, its growth pattern (tall, short, below or above ground), possible negative effects on other plants (such as the allelopathic effects of sunflowers and Jerusalem artichokes on nearby plants), preferred season, and light, nutrient and moisture requirements. Interplanting can be accomplished by alternating rows within a bed (plant a row of peppers next to a row of onions), by mixing plants within a row, or by distributing various species throughout the bed. For the beginner, alternating rows may be the easiest to manage at first.
Long-season (slow to mature) and short-season (quick to mature) plants like carrots and radishes, respectively, can be planted at the same time. The radishes are harvested before they begin to crowd the carrots. An example of combining growth patterns is planting smaller plants close to larger plants, radishes at the base of beans or broccoli. Shade tolerant species like lettuce, spinach, and celery may be planted in the shadow of taller crops. Heavy feeders, such as cabbage family crops, should be interplanted with less gluttonous plants.
Interplanting can help keep insect and disease problems under control. Pests are usually fairly crop-specific; that is, they prefer vegetables of one type or family. Mixing families of plants helps to break up large expanses of the pest-preferred crop, helping to contain early pest damage within a small area, thus giving the gardener a little more time to deal with the problem. One disadvantage is that when it does come time to spray for pests, it's hard to be sure that all plants are protected.
Individual plants are closely spaced in a raised bed or interplanted garden. An equidistant spacing pattern calls for plants to be the same distance from each other within the bed; that is, plant so that the center of one plant is the same distance from plants on all sides of it. In beds of more than two rows, this means that the rows should be staggered so that plants in every other row are between the plants in adjacent rows. The distance recommended for plants within the row on a seed packet is the distance from the center of one plant to the center of the next. This results in an efficient use of space and leaves less area to weed and mulch. The close spacing tends to create a nearly solid leaf canopy, acting as a living mulch, decreasing water loss, and keeping weed problems down. However, plants should not be crowded to the point at which disease problems arise or competition causes stunting. Refer to Table 10.12 for recommended spacing in intensive gardens.
Succession and relay planting Top
Succession planting is an excellent way to make the most of an intensive garden. To obtain a succession of crops, plant something new in spots vacated by spent plants. Corn after peas is a type of succession.
Planting a spring, summer, and fall garden is another form of succession planting. Cool season crops (broccoli, lettuce, peas) are followed by warm season crops (beans, tomatoes, peppers), and where possible, these may be followed by more cool-season plants, or even a winter cover crop.
Relaying is another common practice, consisting of overlapping plantings of one type of crop. The new planting is made before the old one is removed. For instance, sweet corn may be planted at 2-week intervals for a continuous harvest. This requires some care, though; crops planted very early are likely to get a slower start because of low temperatures. In the case of corn, it can be disastrous to have two varieties pollinating at the same time, as the quality of the kernels may be affected. Give early planted corn extra time to get started, for best results.
Another way to achieve the same result is to plant, at once, various varieties of the same vegetable; for example, you can plant an early-season, a mid-season, and a late-season corn at the same time and have a lengthy harvest.
Starting seeds indoors for transplanting is an important aspect of intensive gardening. To get the most from the garden plot, a new crop should be ready to take the place of the crop being removed. Several weeks may be gained by having 6-inch transplants ready to go into vacated areas. Don't forget to recondition the soil for the new plants.
Intensive Garden
Planning an intensive garden Top
Begin planning your garden early, pull out last-year's garden records and dig into the new seed catalogs. As with any garden, you must decide what crops you want to grow based on your own likes and dislikes, as well as how much of each you will need. An account of which cultivars were most successful or tasted best is helpful in making crop choices. Use the charts below, and your own experience, to determine which crops are likely combinations.
Good gardening practices such as watering, fertilizing, crop rotation, composting, and sanitation are especially important in an intensive garden. An intensive garden does require more detailed planning, but the time saved in working the garden and the increased yields make it well worthwhile. Use your imagination and have fun!
Table 10.12


Plant Inches Plant Inches
Asparagus 15 - 18 Lettuce, head 10 - 12
Beans, lima 4 - 6 Lettuce, leaf 4 - 6
Beans, pole 6 - 12 Melons 18 - 24
Beans, bush 4 - 6 Mustard 6 - 9
Beets 2 - 4 Okra 12 - 18
Broccoli 12 - 18 Onion 2 - 4
Brussels sprouts 15 - 18 Peas 2 - 4
Cabbage 15 - 18 Peppers 12 - 15
Cabbage, Chinese 10 - 12 Potatoes 10 - 12
Carrots 2 - 3 Pumpkins 24 - 36
Cauliflower 15 - 18 Radishes 2 - 3
Cucumber 12 - 18 Rutabaga 4 - 6
Chard, Swiss 6 - 9 Southern pea 3 - 4
Collards 12 - 15 Spinach 4 - 6
Endive 15 - 18 Squash, summer 18 - 24
Eggplant 18 - 24 Squash, winter 24 - 36
Kale 15 - 18 Sweet corn 15 - 18
Kohlrabi 6 - 9 Tomatoes 18 - 24
Leeks 3 - 6 Turnip 4 - 6

Note: To determine spacing for interplanting, add the inches for the two crops to be planted together, and divide the sum by 2. For example, if radishes are planted next to beans, add 2 inches + 4 inches = 6 inches, then divide 6 inches by 2 inches = 3 inches. The radishes should be planted 3 inches from the beans.
Economic value of crops
It is difficult to evaluate the economic value of crops grown in the vegetable garden due to the different lengths of time they require for maturity and harvest, the availability of varieties and vegetables types not generally found in the marketplace, and the lack of comparison values for vegetables that are not acceptable by commercial standards (cracked tomatoes, crooked cucumbers, etc.), but which are perfectly usable by the gardener. Nevertheless, several studies have attempted to determine which crops bring the most value per square foot of garden space, partly to aid small-space gardeners in making decisions about what to plant. Of course, if no one in the family likes beets, there is no point in growing them just because they are economically valuable, but this list may help you determine which vegetables to plant and which to buy. Perennial crops are not on the list below because each of the studies was on a one-season basis. Asparagus, rhubarb, horseradish, and other perennial crops do also have considerable economic worth. Fruit trees and shrubs are also valuable producers, especially considering the long-term.
Top 15 Vegetables in Economic Value:

Tomatoes Beets
Green bunching onions Carrots
Leaf lettuce Cucumbers
Turnip (green + roots) Peppers
Summer squash Broccoli
Edible pod peas Head lettuce
Onion storage bulbs Swiss chard
Beans (pole, bush)  
Values based on pounds produced per square foot, retail value per pound at harvest time, and length of time in the garden.
Low-Value Crops (not recommended for small spaces):

Corn Squash
Melons Pumpkins
Miniature varieties or trellising may increase value per square foot.

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