How many varieties of strawberries are you growing, if only the one then try some others to see if they perform better with this.

It's only sequoias because I'm only interested in large strawberries. This picture actually comes from a volunteer plant from some helpful bird who deposited a seed from a faraway bed. I have some sequoias growing in pots after not growing any strawberries for 3-4 years, so we'll see how they do.