   Intensive Gardening - January 23, 2002 Jeff Schalau, County Director, Agent, Agriculture & Natural Resources Arizona Cooperative Extension, Yavapai County As the seed catalogs begin to arrive, we begin to dream of spring planting and summer harvests. If you are like me, you want to plant new crops or varieties while still growing the standby crops that have been successful in the past. This will require planning to maximize the available growing area. Maximizing your growing space not only allows you to grow more, it also cuts down on the space where weeds can grow. The book, "Square Foot Gardening" by Mel Bartholomew (1981) is the benchmark reference for gardening in limited space. Bartholomew's book is useful in learning this technique and provides those with limited experience the knowledge to succeed. However, anyone can practice the "square foot" philosophy by knowing the above and below-ground space requirements, shade tolerance, nutrient needs, and growing season for each crop being planted. Square foot gardening is really just another name for intensive gardening. The foundation of successful intensive gardening is in soil preparation and creating raised beds. Raised beds warm up faster in spring and create a deeper soil environment. Plan your beds so that they are 3-4 feet wide and leave space for walking between them so that soil compaction is minimized. Double dig the beds by removing the upper 10-12 inches of soil from a small area placing it on the adjacent soil surface. Use a spading fork to loosen the soil at the bottom of the hole to an addition 10-12 inch depth. Place copious quantities of compost in the hole, replace soil from the adjacent area, and mix well. The bed should be fluffy and slightly raised. Organic nitrogen fertilizer can also be added at this time. Phosphorus should be placed directly in the root zone (6-8 inches deep under planted area). Another way to maximize garden space is the use of trellises, strings, cages, or poles to provide vertical support to growing plants. Cucumbers, tomatoes, some melons, and pole beans are well suited to this practice. Vertically supported plants will cast a shadow, so plant shade tolerant plants (e.g. lettuce, spinach, celery) in the resulting shade. This practice can also increase irrigation requirements due to greater exposure and subsequent increases in transpiration rates. Vertical support can also decrease the incidence of fungal diseases due to increased air circulation. Interplanting or companion planting can be used to maximize space and enhance the growth of some plants. Native Americans planted the "three sisters": squash, beans and corn. Beans fix nitrogen to augment the relatively high nitrogen requirements of corn. Squash grows as a ground cover to shade out weeds. Companion planting is a major topic unto itself and this column cannot get into the minute details. If you want more information now, there are some good books available on this topic including "Companion Planting" by Richard Bird and "Rodale's Successful Organic Gardening Companion Planting" by Susan McClure and Sally Roth. Be aware that the research base is limited for this topic and much of the published information, no matter how well it works in individual situations, is anecdotal. I know of a useful web site: Appropriate Technology Transfer for Rural Areas at www.attra.org. This site has some of the most reliable, unbiased information that I am aware of. Spacing is the most critical decision made when maximizing use of garden space. When planting in rows, stagger the plants in adjacent rows so they are equidistant from each other. Rows need not be used. Planting can be freeform and spacing determined by individual plant size. Use graph paper and draw your garden to scale. Map the area needed for each crop. For crops like lettuce and spinach, leave some openings for successive plantings. Keep this in a notebook to record your successes and potential for improvement. The Arizona Master Gardener Manual has a list of crops and their space requirements. It is available on the web (ag.arizona.edu/pubs/garden/mg/) or by request from the Cooperative Extension office. The best use of small garden spaces is to plant higher value crops. These include: leaf lettuce, turnips, summer squash, edible pod peas, green beans, carrots, cucumbers, peppers, broccoli, head lettuce, chard, tomatoes, beets, bunching onions, and onion storage bulbs. Asparagus, rhubarb, horseradish, and other perennial crops also have significant value. Relatively low value crops include: corn, melons, winter squash, and pumpkins. If space is limited, you may be better off buying these crops from a local stand or farmer's market. For most of us, intensive gardening is the best way to use our limited garden space. It also allows us to create aesthetically unique and artful gardens. If plants grow too close together, simply thin out your least favorite crop. Don't be afraid to plant flowers in your vegetable garden. They add color and can provide some pest repelling qualities (i.e. marigolds). Your vegetable garden should be fun and attractive. This will entice you to stay there to weed, water, and enjoy yourself. So, start dreaming, make some drawings, make compost, and be ready for spring planting. The University of Arizona Cooperative Extension has publications and information on gardening and pest control. If you have other gardening questions, call the Master Gardener line in the Cottonwood office at 646-9113 or E-mail us at mgardener@verdeonline.com and be sure to include your address and phone number. Find past Backyard Gardener columns or submit column ideas at the Backyard Gardener web site: http://ag.arizona.edu/yavapai/anr/hort/byg/. |