Phacelia
Phacelia tanacetifolia · Hydrophyllaceae
The gardener's calendar
Ideal time to plant phacelia: set it out when the soil is neither frozen nor waterlogged, and water generously as it establishes.
ID card
- Scientific name
- Phacelia tanacetifolia
- Family
- Hydrophyllaceae
- Type
- Annual herbaceous plant
- Flowering
- May to September
- Adult size
- 40 to 80 cm in height
- Growth
- Fast
- Hardiness
- Frost-sensitive, annual cultivation
- Origin
- California (United States)
- Foliage
- Deciduous, deeply cut resembling Tansy
Care
Light exposure
Phacelia prefers full sun exposure for abundant flowering. It tolerates partial shade but produces fewer flowers. Choose a bright, well-ventilated location to optimize growth.
Soil
This herbaceous plant adapts to many soil types, even poor or sandy ones. It prefers well-drained soil and dislikes waterlogging. Light, fertile soil accelerates growth and enhances flowering.
Watering
Water regularly during growth, keeping the soil slightly moist without waterlogging. Gradually reduce watering after the plant is established. Phacelia tolerates some dryness once rooted.
Fertilizer
A balanced fertilizer application at the start is generally sufficient. Avoid excess nitrogen, which favors foliage at the expense of flowers. Monthly applications of diluted fertilizer can support prolonged flowering.
Pruning and maintenance
No formal pruning is necessary. Remove spent flowers to extend the flowering period. Leave a few flowers at the end of the cycle to allow self-seeding if desired.
Pests and diseases
Phacelia is generally very resistant to diseases. It may occasionally suffer aphid attacks in very humid conditions. Ensure good ventilation and intervene at the first sign with natural solutions if necessary.
Did you know?
Phacelia tanacetifolia is a pioneer plant highly valued by beekeepers and ecological gardeners: its nectar-rich flowers produce abundant nectar that attracts bees and other pollinators in large numbers. It is often sown as a cover crop or green manure to enrich the soil and restore its natural fertility.
Where to buy it
Plant in spring or early autumn, avoiding spells of intense heat. Pick a plant with healthy foliage and roots that are not exposed. Best time: March, April, May, September.
Add this plant to my garden →Plants from the same family
- Virginia waterleafHydrophyllum virginianum
- Distant phaceliaPhacelia distans
- Baby blue eyesNemophila menziesii
- Silverleaf phaceliaPhacelia hastata
- Caterpillar phaceliaPhacelia cicutaria
- CamelliaCamellia japonica
Tips generated and checked by Viridia — adapt them to your local climate.