Plant care
Hosta 'First Frost'temperature & humidity
Hosta 'First Frost'
More about hosta 'first frost'
Ideal temperature for hosta 'first frost'
Temperature kills fewer hosta 'first frost' plants than you'd think. What kills them is the micro-climate within a normal-temperature room — a leaf pressed against single-glazed winter glass, the hot dry updraft directly above a radiator, the cold blast from an AC vent. The thermostat reading at 15-25°C in active growth, fully cold-hardy and dormant in winter (59-77°F in active growth, fully cold-hardy and dormant in winter) is fine; the spot you put the plant in matters more. Below roughly 15°C growth pauses; cold beyond that pushes it into dormancy rather than killing it outright.
Cold tolerance & winter care
Hosta 'First Frost' is comparatively hardy (USDA 3-9, RHS H7). 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 hosta 'first frost'
Hosta 'First Frost' sits happiest at around Ambient outdoor humidity (40-70%) relative humidity. A shade-border perennial happy with moderate to high humidity. No special humidity provision is required outdoors. 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.
Hosta 'First Frost' temperature & humidity — frequently asked questions
What temperature is best for hosta 'first frost'?
Hosta 'First Frost' grows best between 15-25°C in active growth, fully cold-hardy and dormant in winter (59-77°F in active growth, fully cold-hardy and dormant in winter). 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 hosta 'first frost' tolerate?
Hosta 'First Frost' starts to suffer below roughly 15°C. It tolerates a cold dormant period within USDA 3-9, but a wet cold root zone is more dangerous than cold air.
What humidity does hosta 'first frost' need?
Hosta 'First Frost' prefers about Ambient outdoor humidity (40-70%) relative humidity. A shade-border perennial happy with moderate to high humidity. No special humidity provision is required outdoors.
How do I raise humidity for hosta 'first frost'?
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 hosta 'first frost' live outside?
Hosta 'First Frost' is rated for USDA zone 3-9 and RHS hardiness H7. 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 hosta 'first frost' care
In the UK? Keeping hosta 'first frost' warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full hosta 'first frost' care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.