How to Grow Starflower

Starflower

Borago officinalis

herb

Starflower, also known as borage, is an annual herb with distinctive star-shaped blue flowers and fuzzy stems and leaves. It is valued for its edible flowers, leaves with a cucumber-like flavor, and numerous culinary and medicinal applications. The plant is easy to grow and attracts pollinators and beneficial insects to the garden.

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Example Starflower timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Starflower

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Starflower

    Around Jun 16

    ≈ 60 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Starflower dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily; tolerates partial shade
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Water: Moderate water needs; drought-tolerant once established. Water when soil is dry 1 inch below surface. Avoid overwatering as it promotes leaf growth over flowers.
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Spacing: 12 inches
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Days to maturity: 60-70 days to first flowers
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Planting depth: 0.25 inches for seeds; direct sow as it dislikes transplanting

Soil

Type: Well-draining sandy or loamy soil
pH: 6.0-7.0
Amendments:
Compost Perlite for drainage Avoid excessive nitrogen

Growing Zones

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Thrives in zones 2-9; grows as annual in most regions, perennial in warmer zones

2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a

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Growth Stages

1

Germination

1-2 weeks

Seeds sprout and cotyledons emerge; fuzzy texture begins to develop

Keep soil lightly moist; germination occurs in 7-10 days at 60-70°F. Thin seedlings to proper spacing early.

2

Seedling & Vegetative Growth

3-4 weeks

True leaves develop with distinctive hairy texture; plant grows bushy with multiple stems

Gradually reduce watering frequency. Avoid high nitrogen to prevent excessive leaf growth. Support stems if needed in windy locations.

3

Flowering

6-8 weeks, extends with deadheading

Star-shaped blue (occasionally pink or white) flowers appear in terminal clusters; flowers are attractive to pollinators

Deadhead spent flowers to encourage continuous blooming. Harvest flowers regularly for culinary use. Provide consistent watering during peak flowering.

4

Seed Development

3-4 weeks

Flowers fade and seed pods develop; plants may self-seed if flowers are left unharvested

Allow some flowers to mature if self-seeding is desired. Remove bolting plants if you want to focus on leaf and flower harvest.

5

Maturity & Decline

Variable based on climate

Plant begins to decline as temperatures rise in summer or as annual life cycle completes

In cool climates, succession plant every 3-4 weeks for continuous harvest. In hot climates, plant in spring for early season or fall for late season production.

Common Pests

  • Hand-pick beetles; spray with neem oil; encourage natural predators like birds

  • Ensure good air circulation; avoid overhead watering; apply sulfur dust if severe; resistant varieties available

  • Spray with strong water stream; use insecticidal soap; encourage beneficial insects like ladybugs

  • and (beneficial, not pests)

    Avoid pesticides; encourage visitation by providing water and shelter

Uses

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Edible Flowers & Garnish

Culinary

The distinctive star-shaped blue flowers are widely used as a garnish for salads, cocktails, desserts, and special dishes, adding both visual appeal and a subtle cucumber-like flavor. Flowers can be candied, frozen in ice cubes, or used fresh to decorate cakes and other culinary creations. [source]

🍳

Herbal Tea & Beverages

Culinary

Fresh or dried leaves and flowers brew into a refreshing herbal tea with a delicate cucumber-like flavor and mild sweetness. The tea has traditionally been used to cool and refresh, and is popular in lemonade, punch, and other summer beverages. [source]

💊

Anti-inflammatory & Skin Health

Medicinal

Borage seed oil is rich in gamma-linolenic acid (GLA) and has been traditionally used to support skin health, reduce inflammation, and support immune function. The plant contains compounds that may help with conditions like eczema and general dermatological health. [source]

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Pollinator Attraction

Household

Starflower is an excellent pollinator plant that attracts bees, butterflies, and other beneficial insects to the garden. This makes it valuable for improving fruit and vegetable production in companion plantings. [source]

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Salad Greens & Fresh Cooking

Culinary

Young tender leaves add a fresh, cooling cucumber-like flavor to salads, soups, and cooked dishes. The leaves are most tender and flavorful when young; older leaves become tougher and hairier. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Harvest leaves continuously once plant is 6-8 inches tall by pinching off top growth; this encourages bushier plants and more flowers. Flowers are ready to harvest as soon as they open and can be picked throughout the day. For culinary use, harvest leaves in morning after dew dries. Both leaves and flowers are edible and taste mildly of cucumber. Freeze flowers in ice cubes or dry leaves for tea.

Fun Facts

  • 🌱 Starflower has been cultivated for over 2,000 years and was brought to Britain by the Romans, where it became a traditional cottage garden plant known as the 'herb of courage' for its supposed ability to bolster confidence in warriors.
  • 🌱 The plant is a prolific self-seeder and can naturalize in gardens; many gardeners appreciate its ability to volunteer year after year without replanting.
  • 🌱 Bees are highly attracted to starflower, and it is considered one of the best honey plants; the flowers can bloom for months and continuously attract pollinator activity.

Gardening Terms

New to gardening? Learn about terms used in this guide:

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