How to Grow Sweet Annie Plants

Sweet Annie plant (Artemisia annua)


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Sweet Annie plants are a fast-growing, tall annual variety that can reach up to 6 feet in height. Also referred to as sweet wormwood, these plants are known for their sweet-smelling, silvery-green, lacy foliage. Though the flowers of this plant aren't showy or extravagant, the sweet aroma makes up for any lack of bright color.

The branches of Artemisia annua are filled with thousands of tiny yellow blooms that appear in the summer. The flowers are popular choices for flower bouquets or dried flower crafts. In addition, this plant has been used for thousands of years in herbal medicine. The Sweet Annie plant readily self-seeds, making this beautiful smelling plant reappear year after year.

Botanical Name Artemisia annua
Common Name Sweet Annie, sweet wormwood
Plant Type Annual
Mature Size 6 ft. tall, 2ft. wide
Sun Exposure Full
Soil Type Sandy, Well-drained
Soil pH Neutral, Alkaline
Bloom Time Summer
Flower Color Yellow
Hardiness Zones 5-9, USA
Native Area Europe, Asia
Toxicity Non-toxic

Sweet Annie Plant Care

Sweet Annie is a robust plant that does not require much maintenance once established. It thrives in poor soil conditions and makes a great choice for areas where other plants may suffer. However, overly moist soil is the bane of its existence. Provide these plants with well-draining soil, since soggy conditions can cause root rot.

Although it is an annual variety, these plants readily reseed themselves. As a result, aggressive spreading may be an issue for some gardeners. Harvesting the flowers and seed pods before they release the seeds will help prevent unwanted spread. To harvest the flowers, simply cut the flowering branch just as the first yellow blossoms are opening. Add these to bouquets or tie them up and hang them upside down in a well-ventilated, dark place for drying.

It's worth noting that Sweet Annie is deer-resistant and its sweet-smelling foliage keeps pests at bay. As a result, these plants do not usually have problems with pests or diseases.  

Light

Sweet Annie plants grow best in full sun. They can tolerate partial sun, but these conditions may not yield the best results; flowering may be reduced, which is the largest claim to fame for this annual.

Soil

Sweet Annie is a tough plant and can tolerate many soil conditions. In fact, these plants thrive in poor soil that is low in nutrients, as long as the soil is well-draining. It does well in soils with alkaline and neutral pH levels. This plant can suffer from root rot if soil conditions are too moist. 

Water

In keeping with its low-maintenance nature, Sweet Annie has average watering needs and does not need frequent watering. Beware of overwatering and allow the topsoil to dry out between watering sessions.

Temperature and Humidity

These plants prefer moderate temperatures and humidity levels, but aren't overly selective. Because it is such a hardy plant, Sweet Annie can be grown from in USDA hardiness zones 5 to 9. 

Fertilizer

Sweet Annie thrives in poor soil where other plants may not grow. Because of this, fertilizer is not often needed. However, applying well-balanced fertilizer once a year in the spring is an option if you want to encourage healthy growth.  

Are Sweet Annie Plants Toxic?

Sweet Annie is a non-toxic herb often used in herbal remedies. However, contact your doctor or vet if a pet or child has ingested a large amount, which can be potentially dangerous. Its pollen and sap may cause skin irritation or allergies in people with sensitivities to the Asteraceae plant family.

How to Grow Sweet Annie Plants from Seed

Sow Sweet Annie seeds directly in the garden after the threat of frost is gone. Because these plants grow so large, it is not recommended to scatter seeds. Plant each seed a few inches apart and cover very lightly with soil. As seedlings emerge, thin them to around 3 or 4 feet apart to allow ample room for growth. Once they are a few inches tall, you can allow the soil to dry before watering again. 

If you would like to start seeds indoors, plant them in well-draining soil 5 to 6 weeks before the last frost. Lightly cover the seeds with well-draining soil and mist the seeds, keeping the soil moist. Once two sets of true leaves appear, you can move the seedlings to larger containers and begin hardening them off. Plant the seedlings outdoors when the threat of frost is gone.

Potting and Repotting Sweet Annie Plants

Sweet Annie can be grown in containers, which is an easy way to control its natural spread. Start seeds in small starter pots, then replant the seedling to a larger pot when it is at least 2 inches tall. Harden off the seedling and place in a sunny location. When the plant is large enough, transfer to a pot wide and deep enough to support the plant’s large mature size. Be sure the pot has good drainage to avoid root rot.