Down to Earth - by Madison Co. Master Gardeners
A No Digging, Tilling, Plowing, or Turf-Killing Garden—Almost Instantly
To any good cynic, this sounds like pure snake oil. But it’s not. It’s also a wonderful kid-friendly family project. Here’s what you need:
- Select a full sun site close to a water source. Size is up to you, but will range from about 4’x6’ at a minimum, to as big as you can handle. Soil on the site can be pure bedrock, clay, sand, or wonderful loam. It just shouldn’t be contaminated with petroleum or pesticides.
- Lay hardware wire on the garden site if you fear digging critters. Otherwise, arrange straw (not hay) bales, strings to the outside, to form a tight perimeter. Straw bales that have gotten wet will be fine as long as they remain intact.
- Fill the center area that the bales surround with good quality compost, soil, well rotted manure, or a combination thereof. The cleaner your soil, the fewer weeds to worry about. Put 3” or so of the soil mixture over the tops of the bales, as well. The center, all-soil portion should be reachable from all sides and will allow root vegetables like beets, potatoes, radishes, carrots, etc. to thrive.
- Water the straw daily with a weak organic fertilizer solution to start the degrading process. Fish emulsion or plant-based fertilizers work well in a hose-end sprayer. Insert you hand into the straw occasionally to monitor the temperature. When it falls, after about 10 days, the garden is ready for planting.
- Plant vegetable plants, seeds, or bulbs as you prefer. Plant roots can be placed directly into the straw and the covering of soil. Seeds can go directly into the soil. Pre-soaked seeds sprout more quickly. Follow label directions for planting times and density.
- Plan your watering strategy. The one downside to this design is that it needs regular watering. You want low pressure spray delivered to all plants often enough to keep them growing. Black weeping soaker hoses wound throughout the garden work relatively well, but the newer fabric-covered soaker hose variety eliminates the occasional more powerful spurt that the older version allows. Hoses can be regulated by a timer for greater convenience.
- Extend the growing season by doing successive plantings as space becomes available.
- Find a use after frost for your resulting pile of high quality compost. It’s black gold, completely void of snake oil!!
Gardening in Iowa Zones
“A man who works with nature has a strong ally. A man who works against nature has a formidable foe.” E. A. Anderson. This spring, remember to check the recommended garden zone when purchasing new plants. You’ll be working in harmony withnature when you choose plants suited to your location.
- USDA Plant Hardiness Zone Map: This has been the U.S. industry standard for the past 40 years. The country is divided into 11 zones based on average annual minimum temperatures. The 1990 version of this map puts the northern half of Iowa in Zone 4 (-30 to -20 F) and the southern half in Zone 5 (-20 to -10 F).
- “New” USDA Plant Hardiness Zone Map: Revised in 2003, this map has not been fully adopted by the horticulture industry. Drawing on average lowest winter temperatures from 1986 through 2001, this map moves most of Iowa to Zone 5, with some small areas of Iowa in Zone 4 or Zone 6.
- American Horticulture Society Plant Heat Zone Map: Plants also can be damaged by extreme heat. This map divides the country into 12 zones based on the average number of days that the temperature exceeds 86 degrees F. Generally, northern Iowa is in heat zone 5 (30 to 45 days) and southern Iowa is in heat zone 6 (45 to 60 days).
- Four-code system: This method combines the USDA Plant Hardiness Zone map and the AHS Plant Heat Zone map. For example, a plant with the code 3-7,9-3 will survive in hardiness zones 3 through 7 and heat zones 3 through 9, making it a good choice for Iowa gardens.
ISU publication RG 215 “Gardening in Iowa Zones” includes maps of the three types of zones described above. It is available for download at www.extension.iastate.edu. Or, you can find your USDA hardiness zone by zip code at http://planthardiness.ars.usda.gov. Another fun resource is http://mesonet.agron.iastate.eduwhere you can find detailed historical climate data and graphs.
Don’t have access to a computer? Stop by your local ISU Extension and Outreach Office. We’ll help you find what you’re looking for.
