Question
What are the proper soil types needed for lilacs, potentilla, blueberries and forsythia.  None of my plants have been doing well.  We have sandy soil and are in zone 4.
Thank you

Answer
Lilacs, Forsythia and Potentilla are not usually fussy about soil pH or soil texture, however in my experience these plants do better on heavier clay textured soils.
Blueberries on the other hand are quite fussy about the soil they grow in. Blueberries are ericaceous plants requiring an acidic soil pH of about 5.5.  They also prefer deep organic soil.

Rgds,

Dr Dean Marston.