First hydrangeas provide the same long flowering season as most annuals but won’t need to be replaced annually. At the end of the season bring them into the garage which will hold enough heat through the winter to prevent any dieback, Another option would be to place them in the bulkhead. However it’s still important to water them several times throughout the winter. Even though they are dormant their roots are still pulling moisture from the soil.
Next they have a relatively compacted root system which allows them to remain in a reasonably-sized container for years without becoming pot-bound. A container that is eighteen to twenty-four inches in diameter and height can hold a four foot tall hydrangea. Be sure that the container has drainage holes in the bottom. For the soil mix you should use a quality potting soil but mix in some topsoil to provide a better soil structure.
Finally while in containers it is much easier to control the hydrangea’s color. If you struggle with adjusting your native soils to obtain the deep blue or crimson red color placing them in containers allows you to closely monitor the soil pH content. By adding aluminum sulfate or dolomitic lime in small amounts you can easily balance the pH to your satisfaction.
1. Hydrangea ser. ‘Blue Deckle’
2. Hydrangea macro. ‘Rotdrossel’
3. Hydrangea macro. ‘Masja’
4. Hydrangea macro. ‘Amethyst’
5. Hydrangea macro. ‘Fuji Waterfall’
6. Hydrangea macro ‘Ayesha’
7. Cityline® Dwarf Hydrangea series
8. Hydrangea pan. ‘Tardiva’ tree standard
9. Hydrangea pan. Bobo®
10. Hydrangea pan. Little Quickfire®