Yucca filamentosa 'Excalibur' forms rosettes of spiky, strap-like leaves coloured blue-green to powdery blue.

Yucca filamentosa 'Hofer's Blue' forms rosettes of spiky, strap-like leaves coloured in a bold silver-blue.

Yucca rigida is a dramatic, trunk-forming, hardy species with a crown of stiff, sword-like, powder blue leaves.

Yucca rostrata has a beautiful, spherical powder blue crowns. It will develop a trunk and form an upright, unbranched tree.

'Sapphire Skies' is a super hardy Yucca rostrata with domes of excellent baby blue foliage.

Zaluzianskya or night phlox has deep pink buds opening to night-fragrant white flowers in multitudes for months. A Phoenix Perennials best seller.

Zantedeschia 'African Gold' has deep green foliage with striking gold veins and big pure white calla lily flowers.

Zantedeschia aethiopica 'Green Goddess' has white calla lily flowers with their tips dipped in rich green.

'White Giant' is a fantastic, steroidal selection of Zantedeschia with 5 foot high foliage and 7 foot tall flower stems with huge white flowers.

Zantedeschia aethiopica 'White Giant' (South Africa) is a large grower with all green leaves and large, white flowers.

Zantedeschia 'Albomaculata' is a spotted calla lily with ivory-white trumpet-shaped flowers.

Zantedeschia 'Creme/Cream' is a spotted calla lily with creamy white and green flowers.

Zantedeschia 'Kiwi Blush' is subtle yet stunning with white spathes with pink bases.

Zantedeschia 'Snow Storm' has pure white trumpet-shaped flowers with green bases and bright green leaves with white spots.

Zephyranthes candida or white rain lily is an amaryllis relative with icy white, star-like flowers centred with yellow.