I mix 3 parts Fir Bark - fine grade, 1 part Peat Moss, and 1 part Perlite. Fine Fir Bark decomposes slowly, Perlite is inorganic and peat moss is already decomposed organic matter, so this potting mix will last a long time (several years).
The most important characteristic of this potting mix is that it drains water very well. Strawberry plants do not want to sit in water, so having a well draining potting mix is essential.
I then sprinkle Dynamite Plant Food for Flowers and Vegetables. This is a Controlled Released Fertilizer (CRF) and suppose to last 9 months. I use a CRF because it releases nutrients slowly and will not burn the plants.
I throughly mix the ingredients together and pour the contents into the bucket (see picture to the right)
I leave about an inch between the top of potting mix and the top of the bucket, so that I can put in layer of Miracle Gro Moisture Control Potting Mix.
I find that the park-perlite-peat moss potting mix drains water too quickly. Water goes straight down without spreading to the rest of the mix.
I am using drip irrigation to water, so only a small area will get water.
I use the Miracle Gro Moisture Control Potting Mix to spread the water evenly across the Potting Mix. Water will not immediatly penetrate through the layer of Miracle Gro Moisture Control Potting Mix and will instead distribute itself throughout the Strawberry Tower layer.
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