You might have seen it pop up on your Pinterest feed — cabbage, herbs or even flowers grown out of straw bales.
“It’s the hot new gardening trend,” said Holly Froning, program coordinator for the master gardeners for the University of Illinois Extension.
But this is more than just a trend, Froning added, at a seminar at the Bourbonnais Public Library last week.
“You can grow earlier in the spring and later in the season than using soil,” she explained. “All said and done, you gain about six weeks.”
Straw-bale gardening is a great option for those without a lot of space, because you can grow out of both the top and sides of the bale, and bales can be placed on concrete or asphalt. Because of their height, straw bales are a great alternative to raised-bed gardening and the straw, after conditioning, is incredibly fertile. You also can plant multiple times in the bale within one year, such as radishes in the spring and kale in the fall.
The bales last at least two years and can be used in composting or to enrich the ground.
When buying bales, usually about $5 each, be sure to check that they are made completely out of straw and came from a field without pesticides or germicides, which can inhibit some of your vegetables’ growth. Here are a few more tips from Froning’s talk.
Pick a location that gets at least six hours of full sun. Place the bale so the open end of the straw is placed upright and the twine is wrapped around the side. (If the twine is placed underneath the bale, it’ll rot.) If placing the bales on the lawn or bare soil, place four to five sections of newspaper under the bales, with several inches sticking out of the base, to prevent weeds.
If you want to walk between bales, position them 4 to 6 feet apart.
Conditioning is the process by which you fertilize the bale and make it ready for planting. Make sure to do the conditioning in the final place you want the bales, because they will get heavy. As they start to decompose, they also will begin to heat up.
Days 1-3: Water bales thoroughly with water mixed with three cups of organic fertilizer. Keep them wet for three days.
Days 4-6: Sprinkle water mixed with one cup of organic fertilizer each day.
Days 7-9: Sprinkle water mixed with 1/2 cup of organic fertilizer each day.
Day 10: Sprinkle three cups of fish or bone meal (you can buy the dry grains at a garden center). Keep the bales moist.
Check back frequently, keeping the bales moist. Once they have cooled to the touch, in about three to four weeks, they are ready for planting. Mushrooms or other fungus might grow during this process; they won’t affect your plants and you can simply knock them off. However, they are poisonous, so do not eat them.
You can plant with both seeds or transplants. To plant with seeds, cut the top of the straw about 1 inch, leaving a lid around the edges. Cover with a layer of soil. Place dampened paper towels down, place seeds where you want them, and cover again with damp paper towels. Cover with another layer of soil.
To plant transplants, simply make a hole in the top of the bale. Loosen the transplant roots, place the plant in the hole and gently firm the straw and some potting soil around the roots. Water immediately after planting and daily.
Fertilize the straw once per week with a water soluble garden fertilizer with nitrogen, phosphorus, potassium and micronutrients.