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Strawberries are really easy to grow but have some drawbacks. Planting in straw bales is a good idea because they usually drain exceptionally well.
To start, buy oat straw bales, not grass and make sure they are straw and not hay which has many seeds. Also, if possible buy organic because you are going to be eating the strawberries. If there is some oat seed in the straw and it grows, it is easy to pull out. With grass you will be there all day and the next getting rid of unwanted growth.
Put the bales in full sun and where it will stay permanently. Water the bale for several days, get a composting action started. I usually dig out a rectangular area on top after it is thoroughly wet. Water each day until water comes out the bottom for about three days.
Then dig out 4-5 inches in depth and add potting soil and compost along with a small amount of all purpose fertilizer (check the directions and cut the amount in half). You should also check the pH and if it is too acidic add ag lime per the package's directions (see link I added at the bottom). Adding too much nitrogen in the fertilizer, will make the plant produce leaves and stolons (runners with another plant on the end) and less flowers.
The bale will decompose over time but I have used the large rectangular bales and they have lasted about 3 years before completely breaking down. I also placed them where I wanted to start a compost pile. That worked well. I am attaching a publication from Oregon State on growing strawberries.
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