How to Grow Marine Blue
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Marine Blue
Convolvulus sabatius
flowerMarine Blue is a tender perennial trailing flower known for its delicate, deep blue morning glory-like blooms that appear from spring through fall. This low-growing, spreading groundcover produces masses of small flowers on fine, wiry stems, making it ideal for hanging baskets, containers, and garden edges. It thrives in warm conditions and requires minimal maintenance once established.
When should you plant Marine Blue in your zone?
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Example Marine Blue timeline · Pittsburgh, PA (Zone 6b)
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Plant Marine Blue
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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First Marine Blue blooms
Around Jun 1≈ 45 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Marine Blue dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 9b-11; grown as an annual in cooler zones
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Seedling
2-3 weeksTiny seedlings emerge with cotyledons; delicate, thread-like stems begin to develop.
Keep soil consistently moist but not waterlogged. Provide bright light (grow lights if indoors). Avoid damping off by ensuring good air circulation.
Vegetative Growth
3-4 weeksPlant develops trailing or mounding habit with fine, wiry stems and small, narrow leaves (almost thread-like).
Reduce watering frequency; allow soil to dry slightly between waterings. Pinch back stems to encourage bushier growth if desired. Begin light fertilizing.
Flowering
3-5 months (spring through fall, or year-round in warm climates)Delicate, trumpet-shaped deep blue flowers (occasionally with darker centers) appear along trailing stems, often hundreds on a mature plant.
Maintain moderate watering. Deadhead spent flowers to encourage continuous blooming. Apply balanced fertilizer every 2-3 weeks to sustain flowering.
Peak Production
2-4 monthsPlant reaches full spreading habit with dense flower coverage; continuous blooming occurs under favorable conditions.
Continue regular watering and feeding during active growth. Prune straggly stems to maintain shape. Monitor for pests in warm weather.
Overwintering/Decline
2-4 monthsIn cooler zones, foliage may yellow and blooming decreases as temperatures drop. In warm climates, plant remains active.
In zones 9a and cooler, treat as annual or bring potted plants indoors before frost. In zones 9b+, reduce watering and feeding; prune back in early spring.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Spray with neem oil or insecticidal soap; increase humidity by misting. Remove heavily infested leaves.
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Use yellow sticky traps; spray with insecticidal soap or neem oil on undersides of leaves.
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Remove with cotton swab dipped in rubbing alcohol. Spray with neem oil if infestation is widespread.
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Scrape off manually; apply horticultural oil in early spring before new growth.
Uses
Edible Flowers
CulinaryThe delicate blue flowers are edible and can be used as garnish for desserts, salads, and drinks, adding a subtle floral note and striking color to dishes. [source]
Cut Flower Arrangements
CraftThe fine, trailing stems with numerous blooms are excellent for fresh flower arrangements, garden bouquets, and floral designs, providing height and movement. [source]
Container & Basket Gardening
HouseholdMarine Blue is ideal for hanging baskets, window boxes, containers, and as a cascading border plant in mixed container gardens. Its trailing habit and prolific blooming make it perfect for elevated displays. [source]
Pollinator Support
WildlifeThe numerous blue flowers attract bees, butterflies, and other pollinators throughout the growing season, providing nectar and supporting local pollinator populations. [source]
Groundcover & Garden Border
HouseholdIn warm climates, Marine Blue serves as a low-growing groundcover for small spaces, garden edges, rock gardens, and spillover effects on slopes and terraced areas. [source]
Harvest Tips
Marine Blue is an ornamental flower; harvest blooms by cutting stems for fresh arrangements. Cut stems in the morning when flowers are fully open. Regularly deadheading (removing spent flowers) encourages more blooms and extends the flowering season.
Fun Facts
- 🌱 Marine Blue's scientific name, Convolvulus sabatius, places it in the morning glory family (Convolvulaceae), though it is not a true morning glory but rather a closely related species.
- 🌱 The striking deep blue flowers remain open throughout the day (unlike true morning glories), providing continuous color from sunrise to sunset.
- 🌱 Marine Blue is sometimes called 'Ground Morning Glory' or 'Dwarf Morning Glory' and is native to North Africa, making it naturally adapted to warm, sunny, and dry conditions.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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