Melt butter in a large saucepan; add celery, onion, and garlic, and saute until tender. Add 4 cups water and next 7 ingredients; bring to a boil. Stir in rice; cover, reduce heat, and simmer 20 minutes. Remove from heat, and let stand 10 minutes. Stir in pecans and apple.
Note: Basmati rice is a fine-textured long-grain rice. It can be found in Indian or Middle Eastern markets or the Indian or Middle Eastern departments of supermarkets.