Plumeria rubra "Hydrangea Pink" seeds involves planting seeds from this variety, known for its soft pink, hydrangea-like flowers. Start by soaking the seeds in water for 24 hours to aid germination. Plant them in a well-draining potting mix, keeping the soil slightly moist. Place the seeds in a warm, sunny spot (70-85°F) to promote healthy growth. Germination usually takes 2-4 weeks. Once the seedlings are strong enough, they can be transplanted into larger pots or directly into garden beds.