Plant care
Aster 'Fellowship'temperature & humidity
Symphyotrichum novi-belgii 'Fellowship'
More about aster 'fellowship'
Ideal temperature for aster 'fellowship'
Temperature kills fewer aster 'fellowship' 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 -20 to 28°C (-4 to 82°F) is fine; the spot you put the plant in matters more. Below roughly -20°C growth pauses; cold beyond that pushes it into dormancy rather than killing it outright.
Cold tolerance & winter care
Aster 'Fellowship' is comparatively hardy (USDA 4-8, 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 aster 'fellowship'
Aster 'Fellowship' sits happiest at around 40-65% relative humidity. Powdery mildew is the principal problem for Symphyotrichum novi-belgii; site 'Fellowship' in an open, sunny position with good airflow. Crowded planting dramatically increases mildew severity. 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.
Aster 'Fellowship' temperature & humidity — frequently asked questions
What temperature is best for aster 'fellowship'?
Aster 'Fellowship' grows best between -20 to 28°C (-4 to 82°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 aster 'fellowship' tolerate?
Aster 'Fellowship' starts to suffer below roughly -20°C. It tolerates a cold dormant period within USDA 4-8, but a wet cold root zone is more dangerous than cold air.
What humidity does aster 'fellowship' need?
Aster 'Fellowship' prefers about 40-65% relative humidity. Powdery mildew is the principal problem for Symphyotrichum novi-belgii; site 'Fellowship' in an open, sunny position with good airflow. Crowded planting dramatically increases mildew severity.
How do I raise humidity for aster 'fellowship'?
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 aster 'fellowship' live outside?
Aster 'Fellowship' is rated for USDA zone 4-8 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 aster 'fellowship' care
In the UK? Keeping aster 'fellowship' warm in a UK home covers the radiator, single-glazing and heating-season humidity angle. Temperature and humidity are one piece. See the full aster 'fellowship' care guide, its cold-hardiness guide, and watering schedule — humidity and watering problems are easy to confuse.