Plant care
Foxtail Ferntemperature & humidity
Asparagus densiflorus 'Myersii'
More about foxtail fern
Ideal temperature for foxtail fern
Foxtail Fern is comfortable in any room a person is comfortable in, roughly 18-24 C (65-75 F). The mistakes are micro-climates: a north-facing window on a frosty night, a south-facing windowsill in a summer heatwave, the standing draught between an opened kitchen door and the radiator behind it. Read the room around the plant, not the thermostat. Below roughly 18°C growth pauses; cold beyond that pushes it into dormancy rather than killing it outright.
Cold tolerance & winter care
Foxtail Fern is comparatively hardy (USDA 9-11, RHS undefined). Within that range it tolerates a cold dormant spell outdoors; outside it, grow it in a container you can move under cover or overwinter in a cool but frost-free spot. Hardiness assumes an established plant in well-drained soil — a wet, cold root zone kills far more plants than cold air alone.
Humidity for foxtail fern
Foxtail Fern sits happiest at around 40-55% relative humidity. Prefers moderate humidity of around 40% or higher. Average household humidity is usually adequate, but dry indoor air encourages spider mites. A pebble tray or occasional misting helps in heated or air-conditioned rooms. The usual low-humidity tell is crisp brown leaf tips and edges while the soil moisture is fine — a sign the air, not the watering, is the problem. If you need to raise it, the reliable methods are grouping plants together, standing the pot on a tray of damp pebbles (the pot above the waterline, never in it), or running a small humidifier in winter when indoor heating dries the air most. Misting is the least effective — it raises humidity for minutes, not hours.
Foxtail Fern temperature & humidity — frequently asked questions
What temperature is best for foxtail fern?
Foxtail Fern grows best between 18-24 C (65-75 F). Keep it out of cold draughts, off freezing windowsills in winter, and away from the hot dry air directly above radiators — the extremes matter far more than the average room temperature.
How cold can foxtail fern tolerate?
Foxtail Fern starts to suffer below roughly 18°C. It tolerates a cold dormant period within USDA 9-11, but a wet cold root zone is more dangerous than cold air.
What humidity does foxtail fern need?
Foxtail Fern prefers about 40-55% relative humidity. Prefers moderate humidity of around 40% or higher. Average household humidity is usually adequate, but dry indoor air encourages spider mites. A pebble tray or occasional misting helps in heated or air-conditioned rooms.
How do I raise humidity for foxtail fern?
Group it with other plants, stand the pot on a tray of damp pebbles (kept above the waterline), or run a small humidifier in winter. Misting only helps for a few minutes, so it is the weakest option for a plant that genuinely needs more humidity.
Can foxtail fern live outside?
Foxtail Fern is rated for USDA zone 9-11. Within that range it can stay outdoors; outside it, grow it in a moveable container and protect the roots from a wet, cold winter.
More foxtail fern care
In the UK? Keeping foxtail fern warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full foxtail fern care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.