Answer: If you're watering your dahlia's from above, the water may be rotting the buds before they have a chance to fully develop. Pinch off the brown and soggy buds to promote the development of additional flower buds. When you water, take care to water only the soil, not the leaves, flowers, or flower buds. This should solve the problem for you. Dahlias need full sunshine to perform - be sure yours has all day sun.
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