Purple Tansy is the common name for one of the garden’s supreme workhorses, Phacelia tanacetifolia. Gardeners who have had trouble with fruit setting on squash, melons, or cucumbers need to learn how to improve pollination with Phacelia.
Phacelia is a fast-growing annual that is very easy to manage, and it never gets weedy. Because it matures so quickly, it can be planted until the end of June. Its lacy foliage resembles forms a rosette of leaves that produces from its centre a 100cm (36″) tall flower spike. Each of several inflorescences opens gradually over several days, revealing a series of nectar-rich, mauve flower clusters. Each delicate flower is about 1cm (1/2″) wide, with exceptionally long stamens that give the cluster a hairy look.
This plant stands out as particularly attractive to pollinators, including honeybees and many other wild bee species. Butterflies, and even hummingbirds, are also attracted by the rich supply of sweet nectar.
Hoverflies of the family Syrphidae are also attracted to Phacelia. They prey aggressively on aphids and other pest insects, so Phacelia also works as a general companion plant for pest control.
Phacelia is not a fussy plant. It will grow in nearly any garden soil, in full sun to partial shade. It works in containers and raised beds, or as a border around the vegetable garden.
Organic gardeners should think of Phacelia as an important element in their toolkit. It is an easy, dynamic, and multi-purpose flower.