Straw bale gardening is a different technique for planting vegetables, flowers or herbs. The bales become a kind of organic container to hold your soil/compost mix and into which you plant your seeds or transplants. This requires conditioning of bales in order to decompose their interior enough to allow roots to grow into the straw.
Straw bale gardening is an affordable way to make raised bed gardens. It has the added advantage that no digging is needed, definitely a plus on hard or rocky soils. The bales are readily accessible at any feed store. They can be placed on concrete, asphalt or over areas with bad soil. They can be used in limited spaces. With bales, there are fewer weeds. When their usefulness as a planter is over, usually after a season or so, the straw can be applied around the landscape as mulch.
For bale gardening to be successful, the bales need to be held together with two to three strands of biodegradable baling twine so they don’t fall apart. Even old unrotted bales will work, if held together tightly. Based on your needs and space, position the bales for easy maintenance, sun exposure and watering ease. It takes 10 days or more to prepare straw bales for planting. Conditioning starts with keeping the bales wet for three days. On days four, five and six, sprinkle the top of each bale with one cup of ammonium sulfate (21-0-0) or 1/2 cup of urea (46-0-0), or two cups of organic nitrogen fertilizer. Be sure to water the fertilizer in after applying. The nitrogen in the fertilizer will speed up the decomposition process. Then, on days seven, eight and nine, cut the amount of fertilizer in half. Don’t over water because you don’t want to wash all the nitrogen out of the bales. On day 10, stop the intense fertilizing, but keep the bales moist. To plant, the bales should be at body temperature or lower.
Create pockets three to four inches deep in the top of the bale, remove some of the straw and put in compost. Moisten and then plant transplants or seeds. The number of plants per bale will depend on the space needed by each crop. For example, two cantaloupes, three cucumbers or three to five peppers will fit in one bale. Be diligent in watering because straw dries out quickly and add fertilizer regularly because the straw contains few plant nutrients.
(Taken from Washington State University Extension).
JoAnne Skelly is Associate Professor & Extension Educator, Emerita at University of Nevada Cooperative Extension. She can be reached at skellyj@unce.unr.edu.