Straw Bale Gardening
by Don Brown
Straw bale gardening may offer the solutions to your gardening problems. Heavy clay soil, weeds, an inability to bend, a cold early growing season, wet or dry soils, rock, concrete, driveways, are all problems that can be reduced by growing your garden in bales of straw. Using a bale of straw as the growing medium for your plants allows you to take control of your garden.
Straw is the byproduct of growing cereal grain: wheat, barley, and oats. I have had no experience with flax or rice straw. Cereal grain straw is a hollow segmented straw that will trap and hold water. These hollow straws hold water, increase humidity, and reduce danger of overwatering.
About half of the nutrients used to grow the grain crop is contained in the straw. To release those nutrients, it will be necessary to treat or “temper” the straw and start it to decompose. The bale has two edges: the cut edge and the folded edge. These are the sides of the bale that do not have strings. Stand the bale with the cut edge up.
Use a dowel or hammer and punch five holes in the straw about two inches deep. Fill the holes with blood meal if you are an organic gardener or with a nitrogen fertilizer such as a 34-0-0 for non-organic growing. Water the bale, soaking it, once a day for two days. The bale will start to get hot as the microbes break down the straw. On the third day, punch new holes at different locations in the bale and fill them with your nitrogen source. Water the bale. Repeat one more time. Then water the bale daily until the heat starts to leave the bale, usually 10 to 14 days. Use a thermometer or put your hand into the bale. When the bale is about the temperature of your hand, it is ready to plant. Covering the bale in cold weather with plastic between treatments will speed the process.
Begin the tempering process about 12 days before planting. The heat in the bale may allow a 2 week earlier planting date. By covering the bale and plants with a plastic cover, it has been re- ported to withstand spring night time temperature down to 20 degrees. I cannot confirm this.
The bales can be lined up in a row. Pound a steel “T” post on both ends. Fasten a 2x4 horizontally across the top of the “T” posts and string 14 gauge wire between them. The wire can be used to support plastic over new plantings. The wires will support tall plants and netting over the top bar to protect the plants from varmints. Wire that is used for electric fence works well.
Stack the bales on top of each other to raise the planting surfaces for better accessibility for mobility-limited gardeners.
Insert started plants by digging out a hole in the bale where the plant is to go. Remove the plant from its pot and insert it in the hole. Use a good quality potting soil if needed to fill the hole, and water.
Bales can be planted with seeds. Small seeds that are to be broadcast need a layer of potting soil on the top of the bale to allow the seed to sprout and start establishing roots. Seeds that grow in a bunch can be started by hollowing out a hole and filling it with potting soil. Plant in the potting soil and water. Seeds will require close attention to keep them from drying out, much as they would in a soil garden. Organic fertilizer may be needed to help support the plants. Epson salt is a good source of Magnesium sulfate for tomatoes.
A few grain shoots may come up. If the bale was tempered correctly, those seeds will be sterilized. Do not use soil on the straw bales or weed seeds will be introduced. If the bales are placed on a lawn or weed patch, cover the grass under the bales with card-