Phacelia

Phacelia tanacetifolia, also called lacy phacelia or fiddleneck, is an annual with fern-like leaves and dense clusters of dusty purple-blue flowers. The flowers are very attractive to bees and other insects. Other common names include blue tansy and purple tansy.

Sow seed directly outdoors in spring, on the soil surface just after the last frost. Sowing in spring or early autumn is also given as an option. Scratching the seed coat and soaking the seed overnight can improve germination.

Sow the seed thinly in rows, about ⅛ to ¼ inch (0.3 to 0.6 cm) deep, as soon as the soil can be worked. Seeds sprout in about 7 to 14 days at 55 to 68 °F (13 to 20 °C) and germinate best in cool soil. Keep the soil surface moist until the seedlings emerge.

For blooms through the season, make two or three sowings about 2 weeks apart. Plants need full sun to grow well.

Water. Phacelia is drought tolerant and withstands sandy or rocky soil, but it suffers in waterlogged conditions. Grow it in well-drained soil in full sun.

Size and cold. Plants typically grow 1 to 3 feet (30 to 91 cm) tall and wide. It is winter hardy to about 18 °F (−8 °C). No pruning is required.

Phacelia self-seeds easily and can become weedy in some areas. It is generally pest-free and disease-free.

Phacelia is a skin allergen. Wear gloves and other protective equipment when handling the plant.