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Lacy Phacelia Flowers

Standard · Boraginaceae

Lacy phacelia is a fast-growing annual wildflower with ferny foliage and coiled sprays of lavender-blue flowers packed with nectar. Often called purple tansy or bee's friend, it typically reaches 2 to 3 feet tall and is valued for pollinators, beneficial insects, and soil-building flower mixes. It handles lean, well-drained soil well and performs best when sown into cool to mild conditions before peak summer heat. Key facts: 55–75 days to maturity, 8+ hours of sun, 10–16 " spacing. Can be grown in containers with care (3+ gallon minimum).

Updated April 19, 2026 · Backed by 3 cited sources
Overview

At a Glance

The essentials first: timing, light, spacing, seed-starting, container fit, and overall size.

Days to maturity
55–75 days
Sun
8+ hours
Full Sun, 8 10 Hours
Spacing
10–16 "
between plants
Seed start
0–4 weeks
before transplant
Container
Possible
Needs 3+ gal minimum
Height
2–3 ft
at maturity
Planting window

Zone Planting Guide

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This card updates instantly with viability, frost timing, and any planting notes for your selected zone.

Resilience

Plant Health

Stress tolerance, resistance notes, and the most common problems to watch for as plants mature.

Tolerance
Heat: Moderate Cold: Moderate Drought: Moderate

Common Issues

Damping Off

Cause: Crowded seedlings and saturated soil can rot young stems.

Prevention: Sow thinly, provide drainage, and avoid overwatering.

Lodging

Cause: Excess fertility or shade can make stems floppy.

Prevention: Grow in full sun and avoid high-nitrogen feeding.

Self Seeding

Cause: Spent flowers readily set seed if left in place.

Prevention: Deadhead before seed ripens where spread is unwanted.

Feeding & picking

Nutrition & Harvest

How hungry the plant is, what ripe harvest looks like, and how long the crop keeps after picking.

Feeding
Nutrition
Feeding intensityLow feeder
RecipesWorm Castings Topdress
Timing
Harvest

Cut flowering stems when the first third of the coiled bloom has opened, or let spent coils dry for seed collection.

Expected yield0.05–0.2 lbs/plant
Storage5 days — Best used quickly as a fresh cut filler; dry seed thoroughly before storage.
Plant relationships

Companion Planting

Helpful neighbors can support growth or deter pests. Keep antagonistic plants separated to reduce stress and competition.

Avoid planting near
Herb Fennel
What you'll need

Growing Supplies

Based on Lacy Phacelia's growth profile -- recommendations matched to this variety's specific requirements.

Drip irrigation / soaker hose kit

Every gardener benefits from putting water at the root zone instead of on the leaves, because drip and soaker systems reduce foliar disease pressure by limiting leaf wetness and soil splash. A quality kit should include a backflow preventer, filter, pressure reducer, and UV-resistant tubing.

Source: Iowa State University Extension; Colorado State University Extension; UMass Extension

Soil test kit

A soil test gives a baseline for pH and nutrient status so gardeners can add only what the soil actually needs. Prioritize a mail-in or lab-affiliated kit whenever possible because extension guidance notes that laboratory testing is more accurate than instant readers.

Source: University of Maryland Extension; Purdue Extension; Montana State University Extension

Quality bypass pruners

Extension guidance favors bypass designs because they make cleaner, closer cuts on living tissue than anvil types. Look for hardened steel blades that can be sharpened, a comfortable grip, and a cutting capacity matched to real home-garden stems.

Source: University of New Hampshire Extension; Iowa State University Extension; Purdue University Extension

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Research

Sources

Reference material and extension guidance used to build this growing guide.

seed_catalog Seeds Nowuniversity North Carolina Extension Gardener Plant Toolbox / species referencesreference Cover crop and pollinator strip references
Internal links

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