Answer: Oak Leaf hydrangeas are just too large and floppy to fit into a confined space. You can build homemade supports or use a strong poly twine to tie the branches up into a more upright orientation. However, those Oak Leaf Hydrangeas of yours really need to go in a spot where they can sprawl out and look their best.
If you want to grow an Oak Leaf Hydrangea in that location, you might want to try out one of the dwarf types. 'Pee Wee' and 'Sykes' are compact forms only reaching about 3 to 4 ft tall at maturity.
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