First things first, if you’re going to grow a garden using straw bales, you need at least one straw bale. Hay can also be used if straw is unavailable. While hay has more nutrients to feed the plants, hay bales also cost more than straw. Straw is essentially the stalks of cereal grains that were left behind after harvesting the grains. Straw is not edible; therefore, it is often used as bedding material for livestock raised on the farm. Hay, on the other hand, is an edible food source for animals, so it is often baled for that purpose and if sold off, receives a slightly higher price.
The next item on the list of things to get is fertilizer. Stay away from pesticide laden fertilizers and strive for organic if possible. You will need the fertilizer to condition the straw bales properly for growing a healthy garden. Prior to conditioning the straw bales, we need to choose a location for the straw bale garden to sit. Once you’ve picked a spot to place the straw bales, you need to layer the ground with newspaper, or a sheet of cardboard; this will prevent unwanted weeds from growing up through the straw bale and consuming the nutrients before the plants get a chance to.
Be sure to place the straw bales where you want them, making sure to leave enough space between the bales to allow for foot traffic, and pushing a lawnmower or wheelbarrow through. This is important as the straw bales may become waterlogged during thunderstorms, after which they become immensely heavy and you may not be able to move them again until after harvest.
Straw Bale Conditioning Schedule:
Conditioning of the straw bales is the most time consuming portion of this gardening concept; however, it requires very little effort as nature does most of this work for us. You cannot skip this step. If the straw bales are not conditioned, then they will not become a healthy habitat for growing fruits and vegetables. The conditioning process turns the straw bale into the medium we need for growing the plants we prefer to eat.
Now that the straw bales are in place, grab the garden hose and saturate each bale completely. Once you think the straw bales are soaked, give them another round of water. Repeat this step once a day for the first three days to kick start the conditioning process. This causes the straw bale to begin decomposing. As the bales decompose the microorganisms go to work; this causes the center of the bale to begin heating up.
During this phase of the conditioning process you will need to sprinkle fertilizer over the top of each bale. Conventional fertilizers come in plastic bags. Each of these bags will have three numbers printed on the side. These numbers indicate the levels of nitrogen, phosphorous, and potash the fertilizer mixture has available within it. Purchase ammonium sulfate (21-0-0) or urea (46-0-0). If using ammonium sulfate, sprinkle one cup across the top of each straw bale. If using urea, sprinkle half a cup across the top of each bale. Both of these fertilizers are high in nitrogen which hastens the decomposition process and improves conditioning. After each of the straw bales has been fertilized, water them thoroughly and ensure the fertilizer is saturated into the bale. Repeat this procedure each day of this phase.
During this stage of the conditioning process, simply cut the fertilizer amount in half and repeat the process outlined above for days 4-6; sprinkle half the amount of fertilizer across the top of each bale and water it thoroughly.
Discontinue adding fertilizer to the straw bales, but continue watering them, just enough to keep them moist.
On the 11th day inspect each of the straw bales by touching the surface structure with a bare hand. If the bales feel as though they retain the same relative temperature as your hand, then vegetables can be planted. If the straw bales feel “hot” to the touch, saturate the bale with water again and inspect the bales again on Day 12. The straw bales should feel warm, but not overly hot. Too much heat can damage the plants placed in the bales.
Planting Vegetables in Bales:
You can basically grow any type of vegetable in a straw bale that you can grow in the ground. Having said that, there are certain vegetables that will not produce as well in straw bales as they will in soil. Indeterminate tomato plants and corn are two of the more obvious options to avoid growing in straw bales. Several plant varieties work well as transplants, while others can be sown directly into the bale itself. Lettuce, beans and salad greens are direct sow vegetables, most others should be transplanted.
Using a small hand trowel, carve a hole in the straw bale the size of the root ball for the plant being inserted. Place the root structure into the hole and cover with a small scoop of soil, adding in a little straw as well. Water the plant thoroughly once it is in place. You can normally grow 2-6 plants per straw bale depending on the amount of room they require.
Plants to Avoid:
As mentioned previously, avoid indeterminate tomatoes and corn as they will become top heavy and possibly destroy the straw bale before the plant comes to harvest. Other crops to avoid growing in straw bales include potatoes, carrots, turnips, sweet potatoes, and all other root crops as well.
Additional Tips & Tricks:
Straw bales will dry out rapidly if not watered daily, so keep them moist and manage their watering schedule appropriately. Each straw bale should last throughout an entire gardening season; you shouldn’t have to transplant to other straw bales. Do not water the straw bale garden on days that rain occurs, unless it is a passing cloud that drops very little water as it crosses the garden.
Add fertilizer to the straw bales once every two weeks while the plants are in their early growing stages. Once the plants begin bearing fruit or vegetables, increase fertilizing to once a week.
Straw Bale Concerns:
The single biggest problem straw bale gardeners experience is dried out bales. The simple solution is to water them daily, making sure they are kept moist. During the hotter summer months, you may need to increase the watering schedule to twice daily.
Mushrooms are another “nuisance” of growing plants in straw bale gardens. If you notice mushrooms sprouting from the straw bales, it simply means you’ve done everything right and the straw bales are reacting naturally to the decomposition taking place throughout the gardening process. Do not consume mushrooms that grow out of straw bales!
Straw bale gardening is a concept that is gaining momentum around the world on a daily basis. It is far cheaper than building raised beds, or arranging container gardening arrays, and the straw can be used as mulch after the plants have been harvested, or it can be re-pressed into new straw bales and used for the next gardening project.