Steps for Making a Straw Bale Garden
Straw Bale Selection
Selected a bale of wheat straw, but oat and alfalfa will work. Hay has seeds and the seeds may sprout. Pine straw won’t work because it sheds water and is slow to break down. A bale bound with synthetic twine is ideal because it won’t rot. If the synthetic twine isn’t available, give the bales extra support with wooden stakes.
Arranging the Bales
Use as many bales as your space allows. Even a single bale can be productive. Arrange them end to end in a line or side to side making a square. If the bales are placed with the straw standing vertical, they are easier to plant. The bales will be heavy once you begin the curing process, so place them where you want them before you get started.
Curing the Bale
This step breaks down the interior of the bale to create a soil-like environment, composting the inside. This process takes 3 to 4 weeks if you use an organic source of nitrogen
Step One – Soaking the Bale
Soak the bale with water and keep it wet for 3 days. It will heat up as it begins to compost.
After 3 days sprinkle the bale with blood meal, fish emulsion, compost tea or another organic, high nitrogen product and water it in thoroughly to facilitate the decomposition. Use fish emulsion, undiluted, and pour about 2 cups evenly over the top of the bale and then water it in.
Composting inside the bale really heats things up. The temperature needs to come down before you can plant. Keep the soil moist and re-apply your organic nitrogen periodically until you can feel that the bale has cooled off. This should take about 2 to 3 weeks.
Topping with Compost
Once the bale is cool you are ready to plant. A two or three inch layer of compost or potting soil on top of the straw bale will help keep your plants moist until they become established. This is especially helpful for sowing seeds.
The number of plants per bale depends on the size of the mature plant. Four small vegetables, such as peppers, per bale will work and for large plants like tomatoes, plant two per bale. Vines are particularly suited to straw bale culture, as the bales keep the plants away from ground dwelling pests. For most spreading vegetables, such as squash and cucumbers, each bale can hold two plants. More plants will fit when using smaller plants like greens or herbs. Avoid root crops, and if you grow tall crops, such as corn or pole beans, be sure and use a support system such as staking the bale.
Smaller plants are easier to transplant into bales, so go for younger seedlings that you plant in regular soil.
Use a trowel to pry apart a planting crevice in the bale for garden transplants or you cut quart-sized holes in the bales themselves with a keyhole saw and fill those with a mix of compost and soil.
Fertilizing and Water
Unlike traditional gardening, your plants will be getting next to no nutrients other than what you add to the straw. Fertilize with a liquid, organic fertilizer at half strength with each watering and sprinkle and water in mineral powders such as bone meal or rock phosphate and greensand to add nutrients. Keep the bales moist throughout the growing season and keep an eye on your plants to make sure that they don’t dry out between watering.
After the Growing Season
You should be able to use your wheat straw bales for two years. After that you can compost them, or just break them up where they sit and put new bales over them. This will enrich the soil below and encourage worms to come in and improve it.
Making a Straw Bale
Choose A Sunny Spot since once the bale is wet, it’ll grow heavier to move. Put a piece of cardboard underneath to keep grass and weeds from growing into the bale. Position the bale so the side of cut straw ends is facing up.
Condition the bale before you plant. This process will take around 10 to 14 days. For the first 3 days, water the bale thoroughly so it stays damp. For the next 6 days, in addition to watering the bale, use a liquid fertilizer to add nitrogen to speed the decomposition. Simply add a capful to a gallon of water and pour it all on the bale.
As the bale goes through the conditioning process, the internal temperature may rise to 120 degrees or higher.
On day 10, return to simply watering the bale, and continue doing that until the temperature inside the bale starts to reflect the temperature outside. Use a compost or meat thermometer to keep tabs; you’ll see the temperature start to rise after the first day or two, spike about midway through the process, then start to come back down. Once it reaches ambient temperature, the bale is ready to be planted.
You can grow just about anything in a bale that you can in the ground — with a few exceptions like plants that get too tall and heavy, and can start to break the bale apart. Running plants like sweet potatoes can be harder to grow in a bale. Space plants the same as you would in the ground.
Planting The Bale
Remove straw to form a hole that is as deep as root ball of your plant (though if you’re planting a tomato, of course, you’ll want to go deeper.) Place the plant in the hole, add some quality potting soil around it for extra nutrients and stability, and fill the hole in with some of the straw you removed. Water well. Water And Fertilize plants regularly. Your plants will receive less nutrition from the bale than they would from soil, so fertilize them every week or two. Make sure the bale doesn’t dry out.