Slender Flax Plant Care
Linum tenuifolium L.
Updated · Sources · How we source care data
Linum tenuifolium, the narrow-leaved flax, is a species of flowering plant in the family Linaceae. It is native to central and southern Europe, the Black Sea and Caucasus area, and the northern Middle East as far as northwestern Iran.
Every 7–10 days
Full sun to partial shade
60–80°F
40–60%
At a glance
How do you care for Slender Flax?
Water Slender Flax every 7–10 days, letting the top layer of soil dry out between waterings, and give it full sun to partial shade. It prefers temperatures of 60–80°F (16–27°C) and 40–60% humidity. Fertilize it every 6 months during the growing season.
Where Is the Slender Flax Native To?
What Is the Slender Flax?
Slender Flax (Linum tenuifolium) belongs to the Linaceae family within the Linum genus. Slender Flax is native to central and southern Europe, the Black Sea and Caucasus area, and the northern Middle East as far as northwestern Iran.
Slender Flax displays an upright, branching herb growth habit, reaching up to 2 ft tall with a spread of approximately 1.5 ft. Slender Flax produces delicate five-petaled flowers in shades of blue, pink, or white.
Leaf size: approximately 2 inches.
How Often Should You Water a Slender Flax?
Linum tenuifolium requires watering every 7–10 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 7–10 days
Let soil partially dry between waterings
What Light Does the Slender Flax Need?
Slender Flax thrives in full sun to partial shade.
Light Requirement
Full sun to partial shade
What Temperature and Humidity Does the Slender Flax Prefer?
Linum tenuifolium grows best at temperatures of 60–80°F. Slender Flax prefers humidity levels of 40–60%.
Temperature
60–80°F
Humidity
40–60%
What Soil Mix Works Best for a Slender Flax?
Well-draining sandy loam with added organic matter. Good drainage is essential for Slender Flax to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Slender Flax?
Feed Slender Flax every 6 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 6 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 Slender Flax?
Repot every 1-2 years in early 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 Slender Flax?
Slender Flax can be propagated through seeds, division of clumps. Similar propagation techniques also apply to pale flax plant care, which shares the same genus.
Is the Slender Flax Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Slender Flax, 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 Slender Flax?
Slender Flax 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 Slender Flax Need?
Slender Flax grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. Slender Flax is native to central and southern Europe, the Black Sea and Caucasus area, and the northern Middle East as far as northwestern Iran. In cooler regions, grow Slender Flax as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 13a
Keep exploring plants
Slender Flax 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 Linum genus — compare its care with other Linum species on PlantoScan.
Linum is part of the Linaceae plant family — browse all Linaceae genera and species.
Slender Flax thrives in bright light and direct sun — see other bright-light plants.
More Linum Species
Other Linum species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Linum tenuifolium L., family Linaceae (first published in Sp. Pl. : 278 (1753)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Slender Flax, 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 13a, 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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