Germinating hydrangea seeds can be a challenging process, as hydrangeas are typically propagated through other methods like cuttings or division. However, if you're interested in trying to grow hydrangeas from seeds, here are some general instructions to help you:

1.     Seed Stratification: Hydrangea seeds require a period of cold stratification to break their dormancy. Moisten a paper towel or coffee filter, place the seeds on it, and fold it over to cover them. Put the moistened seeds in a sealable plastic bag and refrigerate them for 4-6 weeks at a temperature around 35-41°F (2-5°C). This mimics the natural winter conditions that hydrangea seeds need to germinate.

2.     Seed Sowing: After the cold stratification period, prepare a seed tray or small pots with a well-draining seed-starting mix. Moisten the soil lightly before sowing the seeds. Sow the hydrangea seeds on the surface of the soil and press them gently into the soil, but do not cover them as they require light to germinate.

3.     Germination Conditions: Place the seed tray or pots in a warm location with indirect sunlight. The ideal temperature for germination is around 68-75°F (20-24°C). Keep the soil lightly moist, but avoid overwatering. You can cover the tray or pots with a plastic dome or plastic wrap to create a humid environment that helps retain moisture.

4.     Seedling Care: Be patient, as germination for hydrangea seeds can be slow and may take several weeks or even months. Once the seedlings have developed several sets of true leaves, they can be transplanted into individual pots or containers. Use a well-draining potting mix and ensure the pots have drainage holes. Provide the seedlings with bright, indirect light and maintain a temperature range of 65-75°F (18-24°C)