Water Hyssop Plant Care
Bacopa arenaria (J.A.Schmidt) Loefgr. & Edwall
Updated · Sources · How we source care data
With its small, round leaves and delicate white flowers, this plant originating from Australia is a favorite among plant collectors for its unique appearance and ability to thrive in both wet and dry conditions. Its adaptability and low maintenance requirements make it a desirable addition to any plant collection.
Every 2–3 days
Full sun to part shade
50–80°F
40–60%
At a glance
How do you care for Water Hyssop?
Water Water Hyssop every 2–3 days, letting the top layer of soil dry out between waterings, and give it full sun to part shade. It prefers temperatures of 50–80°F (10–27°C) and 40–60% humidity. Fertilize it every 4 months during the growing season.
What Is the Water Hyssop?
Water Hyssop (Bacopa arenaria) belongs to the Plantaginaceae family within the Bacopa genus. Water Hyssop is native to Australia, New Zealand. Water Hyssop is also known as Lemon Bacopa.
Water Hyssop displays a trailing, spreading growth habit, reaching up to 0.5 ft tall with a spread of approximately 1.5 ft. Water Hyssop produces small, five-petaled flowers in shades of white, pink, or blue.
Leaf size: approximately 1 inches.
How Often Should You Water a Water Hyssop?
Bacopa arenaria requires watering every 2–3 days. Allow the top layer of soil to dry between waterings to prevent root rot. Reduce watering frequency during winter when growth slows.
Watering Frequency
Every 2–3 days
Let soil partially dry between waterings
What Light Does the Water Hyssop Need?
Water Hyssop thrives in full sun to part shade.
Light Requirement
Full sun to part shade
What Temperature and Humidity Does the Water Hyssop Prefer?
Bacopa arenaria grows best at temperatures of 50–80°F. Water Hyssop prefers humidity levels of 40–60%.
Temperature
50–80°F
Humidity
40–60%
What Soil Mix Works Best for a Water Hyssop?
Moist, well-draining soil rich in organic matter. Good drainage is essential for Water Hyssop to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Water Hyssop?
Feed Water Hyssop every 4 months during the growing season (spring and summer) with a balanced fertilizer diluted to the strength on the label.
Pause feeding in autumn and winter, when growth slows, and never fertilize dry soil — water first.
Fertilizing
Every 4 months
During the growing season
The PlantoScan app can remind you when to water and when to fertilize each plant.
How Do You Repot a Water Hyssop?
Repot annually in spring. Choose a pot one size larger than the current container, and ensure it has drainage holes to allow excess water to escape.
How Do You Propagate a Water Hyssop?
Water Hyssop can be propagated through stem cuttings, division, seeds. Similar propagation techniques also apply to water hyssop plant care, which shares the same genus.
Is the Water Hyssop Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Water Hyssop, so we can't confirm whether it is safe for cats and dogs. Keep pets from chewing it as a precaution.
This is a general caution, not veterinary or medical advice. If your pet ate a plant, contact your vet or animal poison control.
See all plants toxic to cats and plants toxic to dogs.
What Pests and Diseases Affect the Water Hyssop?
Water Hyssop is susceptible to aphids, spider mites, whiteflies. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.
Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.
What USDA Hardiness Zone Does the Water Hyssop Need?
Water Hyssop grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. Water Hyssop is native to Australia, New Zealand. In cooler regions, grow Water Hyssop as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 12a
Keep exploring plants
Water Hyssop is one of many species covered in the complete plant care and identification guide, which groups plants by genus, attribute, and popularity.
It belongs to the Bacopa genus — compare its care with other Bacopa species on PlantoScan.
Bacopa is part of the Plantaginaceae plant family — browse all Plantaginaceae genera and species.
Water Hyssop thrives in bright light and direct sun — see other bright-light plants.
Related Plant Care Guides
Closely related plants with similar care requirements:
Sources
- Scientific name & taxonomy: Bacopa arenaria (J.A.Schmidt) Loefgr. & Edwall, family Plantaginaceae (first published in Bol. Commiss. Geogr. Estado São Paulo 13: 176 (1897)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Water Hyssop, so we can't confirm whether it is safe for cats and dogs. Checked against the ASPCA plant list; any other toxicity note on this page comes from PlantoScan's plant database.
- Hardiness zone: USDA Zone 12a, calculated from the plant's minimum temperature.
- Care values(watering, light, temperature, humidity, soil, fertilizing): PlantoScan's plant database, filtered by automatic plausibility checks — values that fail them are hidden. How we source and check plant data.
Spotted a mistake? Email info@upvision.media with the page link — we check and correct reported errors.
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