If the area you plan to plant is shady enough that lawn won't grow, it's not likely to be sunny enough for blueberries, which need 6-8 hours of sunlight a day. If grown in too much shade, blueberries produce spindly new growth and poor-quality fruits. Lack of moisture is a concern when growing blueberries near a spruce tree. The tree roots soak up most of the available water. Spruce needles will not hurt blueberries if the plants get enough sun. If sunshine in this space is limited, hardy ferns or another shade-tolerant ground cover would be a better choice than blueberries.