Green manure Organic Phacelia. Phacelia tanacetifolia.
Phacelia is a fast growing annual herbaceous plant. It is upright up to 65cms with a beautiful mauve/blue flower head of many flowers from June to September.
It holds onto nitrogen with a shallow root system with a high biomass of lateral side roots, which gives thorough root penetration of the top soil and contributes to good soil structure. The flowers which produce a lot of nectar are very much favoured by insects.
How to grow:
Sow seeds from spring throughout summer after frosts have passed at 2.5g per square metre. Sow shallowly direct into position and roll in well, keep seed bed moist until established. The seed leaves are longer than broad, the first true leaves are lobed and deeply divided.
Phacelia can withstand a light frost when mature so it can overwinter in a mild climate, bare patches may form as a result of frost. It can be grown as part of a mixture of other fast growing annuals like buckwheat, clover or mustards.
This is a fairly problem free plant. It’s non-native to Ireland so it is ideal to turn into the ground before it sets seed – unless you want to save seed from it, which is perfectly feasible. Seeds that do get away and germinate in the next year can be turned in.
Favourite ways to use them:
Perfect for green manure, the fast growing plant material breaks down quickly in the soil.
Average 588 seeds per gram.