As with any royalty, Oak Leaf Hydrangea requires some devotion. Planting must be perfect. In our clay we plant high (3" of roots above ground level) incorporate pine bark mulch into the clay, dig a shallow wide hole, and mulch with pure compost or manure and 1/4 cup blood meal and 1/8 cup 14-7-7 or 12-6-6.
Then add 1 inch of Hardwood Mulch to finish.
 
Water each week the first year or plant in rainy season (Nov.). For sandy soil, plant deeper, (1 inch above grade), amend soil with manure or compost only and fertilizer and hardwood mulch as above. Acidify alkaline soil.
 
Zone 5-9.