Straw is the cut stalks of wheat, barley or oats after the grains or seed heads have been harvested. The straw is compressed and bundled with twine to make bales. They are basically a byproduct but farmers make use of it as bedding for animals and as a mulch in the garden to keep moisture in the soil as well as to keep soil from splashing up onto the plants during watering.
But who ever thought you could grow plants directly in it?
Using the straw to actually grow crops in is a relatively new concept as far as I'm aware.
This process of composting or conditioning would happen normally, overtime, but there are steps the gardener can take to speed up the process so the bales will be ready for planting within a period of two weeks.
Hay bales can also be used but I avoid them as they are a food source to many animals and may attract unwanted guests, such as rodents and rabbits. The process of conditioning, however, would be the same.
Straw is baled in fall. Farmers sell the straw they cut for a nominal fee since this is just a byproduct of their farming. The popularity of straw bale gardening has been a welcome bonus for the farmers who begin selling it as soon as it's baled in Fall. Most people I know buy their bales in Spring, however, as they're planning their summer gardens. The bales can be left out in the rain (or snow) until you're ready to condition them.
Before I start to condition the bales I prepare the areas I will install them and I tie two or three bales together to make a larger planting area, which will hold moisture more proficiently. See my blogs that detail those steps.
The week before I'm ready to start the composting process I begin watering the bales, if we're not getting a steady amount of rain. It helps that they are thoroughly saturated when you begin adding the nitrogen to start the process.
Don't worry if a few seeds were left on the stalks when they were cut and they now begin to sprout. The heat of the composting process will kill them, as well as any unsprouted seeds deep in the bales.
Just keep watering them
Garden centers sell fertilizers that are a combination of chemicals or organic fertilizers, which are substances that are derived from the remains or byproducts of natural organisms which contain the essential nutrients for plant growth. The organic fertilizers take longr to break down but will result in nitrogen being added to the bales.
When using synthetic fertilizers the product is maked with the proportions of the chemicals, Nitrogen, Phosphorus and Potassium (N-P-K: their chemical abbreviations) in numbers. The first number is the one you'll be most concerned about in this instance. Look for a fertilizer with teh highest number in the Nitrogen position. Here I have 32-10-10.
Mix your preferred fertilizer according to the package instructions. I use 3 gallons for a section of two or three bales that I've tied together.
Apply the fertilizer daily for the first 5 days and then every two days for the next 10 days. You should see the straw darken, feel it heat up and begin to smell it as it composts. Success!
Do not be alarmed if, during the process, your bales begin to sprout mushrooms like these inky mushrooms. They are actually helpful in breaking down the straw into a rich growing medium.