In a large bowl, dissolve yeast in warm water. Beat in the milk, sugar, butter, orange zest and salt. Beat in the zucchini, raisins, whole wheat flour, cardamom and enough all-purpose flour to form a soft dough.
Turn onto a floured surface; knead until smooth and elastic, about 6-8 minutes. Place in a greased bowl, turning once to grease top. Cover and let rise in a warm place until doubled, about 1-1/4 hours.
Punch dough down; shape into a loaf. Place in a greased 9x5-in. loaf pan. Cover and let rise until doubled, about 45 minutes.
Bake at 375° for 40-45 minutes or until golden brown. Remove from pan to cool on a wire rack.