Growing Sweet Strawberries
If your strawberries aren’t sweet, look at your current soil conditions. Strawberries perform best in well-drained, fertile and slightly acidic soils. In fact, these plants tend to yield more and are sweeter when grown in compost-enriched, sandy soil.
Planting strawberries in raised beds is also a good idea, as this (along with adequate soil) ensures for better drainage. Raised beds are also easier to maintain.
Another important factor when growing this fruit  is location. Beds should be located where they receive at least eight hours of sunlight, which is essential for producing sweet strawberries.
In addition, be sure your strawberry plants have adequate space to grow. There should be at least 12 inches between plants. Overcrowded plants are more prone to produce smaller yields of sour strawberries.
Additional Care for Sweet Strawberries
Plant your strawberry beds in fall rather than spring to ensure plants have enough time to establish good root systems. Mulch plants with straw  to help insulate your growing strawberries. In cold regions prone to harsh winters, additional protection may be needed .
If you want to ensure a strawberry crop each year, you may want to consider maintaining two separate beds – one bed for fruit bearing, the other for the following season’s plants. Beds should also be rotated to prevent vulnerability to diseases, another cause for sour strawberries.
Generally, you shouldn’t allow strawberry plants to set fruit within the first year. Pick off blooms as they appear to force more energy into producing stronger daughter plants. These are the ones that will yield sweet-tasting strawberries. You’ll also want to keep about 4-5 daughter plants (runners ) to each mother plant, so clip away the rest.http://www.gardeningknowhow.com/edible/fruits/strawberry/sweet-strawberries.htm/print/