How to Grow and Care for Heliotrope in Your Garden

Heliotrope (Heliotropium arborescens) is a shrub-like perennial that blooms with small clusters of purple or white fragrant flowers with a sweet aroma ranging from vanilla to cherry pie. Heliotropes derive their name from the Greek word “helios,” meaning sun, as these flowers require plenty of full sun in order to nurture their showy blooms. Heliotrope can be planted in the garden, in large pots, or indoors as a houseplant.

All varieties of heliotrope contain a liver toxin which acts as a poison if ingested. It is particularly dangerous for animals, but it can also be toxic to humans. Gardeners with pets or small children should consider carefully before planting any heliotropes in their house or garden.

Heliotropes are popular flowers that gardeners prize for their color and aroma. Here are some of the most popular varieties of common heliotrope flowers that you might find at your local nursery.

1. 1. Heliotrope marine: These plants bloom vibrant purple flowers atop vertical green stems. They thrive under warm conditions and their bloom time runs from spring to fall, making them a reliable addition to any colorful garden.
2. 2. Dwarf marine: Dwarf marine heliotropes are a small variety of this flowering plant that is native to Mexico and South America. They bloom in small clusters of light purple flowers with a pleasing sweet scent.
3. 3. European heliotrope: Unlike other varieties, European heliotrope flowers have an unpleasant scent. They bloom in small clusters of white flowers growing on long stems. It is native to Asia, Europe, and Northern Africa, and now grows in many places as a weed.
4. 4. Blue heliotrope: Blue heliotrope grows in South America and boasts uniquely purple-blue flowers. This cultivar is typically grown as a garden heliotrope to attract pollinators. They flower regularly throughout the year.
5. 5. Princess Marina: This evergreen shrub originated in the Andes and blooms in vibrant purple flower clusters. Its wrinkled deep green leaves make the flowers stand out even more. This variety is also sometimes known as the cherry pie flower because of its sweet cherry vanilla scent.

Heliotrope plants take between eighty-four and 120 days to mature, so it is best to start planting them indoors ten to twelve weeks before the last average frost date in your area. This will give your plants a head start once the danger of frost passes and the growing season arrives. Heliotropes are best suited for USDA hardiness zones 9 to 11, and prefer at least six hours of sun a day. If you live in a climate where the sun gets especially hot, make sure that your plant has some afternoon shade.

Follow this simple growing guide to propagate your own heliotrope plants from seed.

• Germinate your seed. You will need to start your seed indoors before transferring it into the soil. Prepare a seedling tray with loamy soil with a pH between 6.5 and 7.3. Bury your seeds about ⅛ of an inch deep in the soil. Water your seeds immediately, and place your tray somewhere sunny to jump-start growth. Your seedling should take about a month to a month and a half to sprout.
• Transfer your seedling outside. Once the weather has warmed up outside, you can transfer your seedling into an outdoor container or directly into the garden soil. Heliotropes do well in full sun so choose a spot in the garden that will get direct sunlight. Continue to water at least once a week to keep the soil moist.
• Feed your plant. Depending on your variety, your heliotrope may benefit from plant food such as fertilizer. For example, Princess Marina heliotropes do well with help from a potash fertilizer. Fertilize your outdoor heliotropes at least once a month, and feed your container-grown heliotropes every two weeks.

Here is a quick overview of how to care for your heliotropes.

1. 1. Water your plant regularly. Moist soil is essential for the healthy growth of your heliotrope. At the same time, you want to make sure your soil drains well to ensure the root system doesn't become overly saturated. For heliotropes in containers or pots, consider regularly refreshing your soil if it becomes too compact.
2. 2. Control growth with pruning. Regularly pruning your plant can help keep it under control and can promote new growth. When your flowers start to wilt, deadhead them. Prune any woody stems that are no longer producing new growth.
3. 3. Look out for pests. Some common pests that heliotropes can attract are aphids, whiteflies, spider mites, and mealybugs. A quick spray with a hose can usually rid your plants of these pests. For more serious cases, treat your plants with neem oil.

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