Phacelia is a very attractive plant and one with a variety of uses.

It is listed as one of the top 20 honey-producing flowers for honeybees. Very rich in both nectar and pollen the lavender-coloured flowers attract bees, butterflies and other pollinating insects like a magnet. This erect annual with finely cut leaves and very dense, curved spikes of beautiful, soft lavender, bell-shaped flowers makes an excellent cut flower and has a long vase-life and strong stems.

Although not a true native of the UK, it is ideal for a wildlife-friendly planting scheme. It is used as a biological control, planted along field margins to attract insects such as hoverflies which then control pests affecting crops. It is often used on set-aside land to improve bee forage in the summer and autumn.

Where areas aren’t required for crops or bedding for a couple of months, put the area to good use by sowing Phacelia as a green manure. Sown onto beds and borders it forms a green carpet that can be dug directly into the soil, improving its organic content. Green manures can also help break up heavy clay soil as their roots grow.
Phacelia is ideal for sowing from March right through until September. It germinates at low temperatures, is tolerant of cold temperatures and is suited to most soils. The fast growing foliage will help suppress weeds, producing lots of organic matter while making an attractive groundcover. This hardy annual, fits anywhere in rotation.

French gardeners are firm believers in the power of cover crops. Even in public spaces such as Paris' Jardin des Bagatelles in the Bois de Boulogne, Phacelia is regularly sown in the autumn as a winter cover crop. If left to flower it is beneficial for bees and insects and is quite simply… a beautiful flower.

Sowing:
Sow in March through to late September
Remove weeds especially perennials and rake the surface of the soil
Scatter the seed thinly at a rate of 1 gm per sq m. (25gm covers 25 square metres ) Cover to a depth of about 1cm (½in) and lightly water in. Dependent on temperature and time of year, Phacelia flowers from 6 to 8 weeks from sowing for around a period of 6 to 8 weeks.

Cultivation:
Easy to grow, if you do not want the plants to set seed, remove the spent flowers as they fade. Phacelia does self-seed very easily so if it is used as a green manure dig in before flowering or cut down and compost the foliage.
Small patches can be left to flower, especially near to vegetables to attract pollinating insects to the area. But don’t have too many as the insects will feed on the Phacelia rather than pollinating the vegetables.
It reaches a height of a foot or more, the ferny leaves may turn red in hot weather

Note:
Although not toxic, contact with some species of Phacelia in some sensitive individuals can cause an unpleasant rash. Wear gloves when harvesting.

Nomenclature:
The species name tanacetifolia means “with leaves like Tansy”
The Phacelia family comes from the Americas, with most species originating in California. Like most of the other 150 or so species, this one is an annual. It has become widely naturalised on European roadsides and is often found in wildflower seed mixes.

Plant Uses:  
Green Manure, Bee Plant, Butterfly Garden, Wildflower Gardens or Wildlife Gardens, Cottage/Informal Garden, Flower Arranging