Without more intimate details of your management practices it would be hard to say exactly why you aren’t getting the desired yields. Do you have any other factors in this field like planting flowers to attract/increase your number of pollinators? Have you looked at your soil biology to see if you have the correct F:B ratios for the crop you’d like to grow well? Are you using inoculants for mychorrhizae? Strawberries like a good fungal population maintained in the soil. Your question could have a lot of answers depending on a lot of factors.