The fine delicate foliage of the rue appears in the spring adding a lovely blue green color to the garden. It is followed later in the summer by the purple-blue flowers of the garden phlox ‘Laura’ that echo the blue of the rue leaves. At summer’s end the phlox fades but the foliage of the rue remains until frost. Both plants thrive in full sun and moist but well-drained soil.
Garden Phlox ‘Laura’ (Phlox paniculata ‘Laura)
Borne in dense heads, the fragrant flowers are richly saturated with color made more striking by their white eye. Dead heading will prolong the bloom time and mulch will keep the roots cool and happy. The foliage is mildew resistant, but watering early in the day is recommended for maximum protection against the fungus.
Bloom Time: Summer
Size: 3-4’ H x 3-4’ W
Hardiness: Zones 4-8
Rue (Ruta graveolens)
Rue is a semi-shrub meaning that it is woody at the base but dies down in the winter. It has clusters of small yellow flowers in early summer which are an asset but the fine blue-green leaves are the great attraction. Native to the Balkans and southeast Europe, rue was grown in monestary gardens in the Middle Ages for its medicinal qualities. ‘Jackman’s Blue’ is a popular cultivar growing up to 30” tall.
Bloom Time: Early summer
Size: 12-36” H x 30” W
Hardiness: Zones 4-9