How to Cultivate and Maintain Heliotropes: Tips for a Flourishing Garden
The heliotrope flower (Heliotropium) is a captivating member of the Boraginaceae family, encompassing around 325 species. Known for their delightful aroma and charming, old-fashioned blooms, heliotropes are a favorite among garden enthusiasts. Their small, clustered flowers follow the sun, a trait that inspired their name, derived from the Greek words helios (sun) and tropos (to turn). While some find their scent reminiscent of vanilla, others detect a hint of cherry pie. Ideal for planting in the spring after the frost has passed, heliotropes add a touch of elegance to any garden. Note, however, that these plants are toxic to both humans and animals.
Common Name: Heliotrope, cherry pie plant
Botanical Name: Heliotropium
Family: Boraginaceae
Plant Type: Perennial
Mature Size: 1-4 ft. tall, 6-8 in. wide
Sun Exposure: Full
Soil Type: Well-draining
Soil pH: Neutral
Bloom Time: Summer, fall
Flower Color: White, purple
Hardiness Zones: 9-11 (USDA)
Native Area: South America
Toxicity: Toxic to humans and animals
Heliotropes Care
Heliotropes, native to the subtropical regions of Peru, are typically grown as annuals outside their native range due to their frost sensitivity. These plants are considered low- to medium-maintenance, benefiting from consistent care.
Light
- Sun Requirement: Heliotropes thrive in full sun and need at least six hours of direct sunlight daily. They prefer morning sun and may suffer from sunburn if exposed to intense afternoon rays.
- Ideal Location: A spot with bright morning sunlight and light afternoon shade is optimal.
Soil
- Soil Preference: Plant heliotropes in rich, loamy soil that drains well but retains some moisture.
- Soil Conditions: They favor soil rich in organic matter with a pH between 6.6 and 7.3. Avoid heavy clay soils that retain excess moisture.
Water
- Watering Needs: Heliotropes need consistent moisture. Keep the soil evenly moist without waterlogging.
- Container Care: In containers, heliotropes require more frequent watering due to faster moisture absorption.
Temperature and Humidity
- Climate: They prefer warm days and cool nights but do not tolerate excessive heat or humidity.
- Frost Sensitivity: Highly frost-tender, they should be protected from freezing temperatures.
Fertilizer
- Feeding Requirements: Heliotropes are heavy feeders and require regular fertilization. In the garden, fertilize monthly; in containers, every two weeks.
- Type of Fertilizer: Use a phosphorus-rich fertilizer designed for flowering plants, following the product label for application rates.
Types of Heliotropes
Several popular heliotrope varieties include:
- ‘Princess Marina’ (Heliotropium arborescens): Known for its compact size and quintessential cherry pie scent with violet-purple blooms.
- Clasping Heliotrope (Heliotropium amplexicaule): Also called blue or summer heliotrope, this type attracts pollinators with its bright purple flowers.
- Beach Heliotrope (Heliotropium anomalum): Native to Hawaii, this ground-covering variety features silvery leaves and fragrant white flower clusters.
- Salt Heliotrope (Heliotropium curassavicum): Thrives in salty conditions, producing white blooms with yellow and purple throats.
Propagating Heliotropes
Heliotropes can be propagated from cuttings or seeds. For stem cuttings:
- Select Cuttings: Take 4- to 5-inch green, fleshy stem cuttings.
- Prepare Cuttings: Remove the lower leaves and dip the cut end in rooting hormone.
- Potting: Place the cutting in moistened soil.
- Light and Moisture: Keep the pot in bright, indirect light and maintain moisture.
- Rooting: After a few weeks, once rooted, gradually increase exposure to direct sunlight and transplant in spring.
Growing Heliotropes from Seed
- Starting Seeds: Begin seeds indoors 10 to 12 weeks before the last frost. Maintain temperatures between 70 to 75°F and expect germination within 28 to 42 days.
- Transplanting: Once frost danger has passed, move seedlings outdoors or into containers.
Potting and Repotting Heliotropes
Heliotropes are well-suited to container gardening and are not prone to aggressive growth. They require more frequent watering in pots than in garden beds.
Overwintering
- Indoor Care: Before the first frost, bring container heliotropes indoors. Place them in a cool room with bright, indirect light and water sparingly to prevent drying out. Avoid heat sources that can dry out the soil.
- Spring Transition: Move plants back outside when temperatures consistently exceed 55°F.
Common Pests and Plant Diseases
- Pests: Watch for aphids, mealybugs, spider mites, fungus gnats, and whiteflies. Treat infestations with insecticidal soap or neem oil.
- Diseases: Keep an eye out for fungal issues like powdery mildew, which arises from poor air circulation and warm soil conditions.
How to Get Heliotropes to Bloom
- Encouraging Blooms: Regular pinching and deadheading promote consistent blooming and denser growth. Start pinching in early spring for more prolific blooms later in the season.
- Indoor Blooming: Ensure indoor heliotropes have adequate moisture, light, and fertilizer for optimal flowering.
Common Problems With Heliotropes
- Brown Flower Clusters: May indicate powdery mildew. Remove damaged flowers, adjust watering to prevent dryness, and avoid overwatering.
- General Drooping: Could be due to excessive sunlight or overwatering. Balance moisture and avoid direct scorching.
- Discolored or Brown Leaves: Check for spider mites or whiteflies. Use insecticidal soap if needed and adjust watering practices.
FAQ
What is heliotrope good for? Heliotropes are excellent as fragrant garden borders, in window boxes, or cascading from hanging baskets.
Is heliotrope a good houseplant? Heliotropes are suitable for indoor and container gardening but remember they are toxic to humans and animals.
What does heliotrope smell like? The scent of heliotropes can vary from almonds and vanilla to cherry pie, depending on individual perception.