RHS describes feeding Nephrolepis exaltata during the growing season at about monthly intervals. That wording is not a year-round calendar schedule.
How to fertilize Nephrolepis exaltata
Feed Nephrolepis exaltata with a balanced liquid houseplant fertilizer at half strength, about monthly during the growing season.
Plant coveredNephrolepis exaltataBoston fern · indoor container
Check for active growth
When to fertilize
The RHS instruction is limited to the growing season. With lower light and temperature in winter, do not assume the same feeding routine. No precise stop or restart date is set for every indoor Boston fern.
Follow the product label
Fertilizer type and dose
Use a balanced liquid fertilizer suitable for houseplants. The cited profile does not require a particular brand or fertilizer analysis.
RHS specifies using the balanced liquid fertilizer at half strength. Do not infer a volume per pot or override the product label.
Inspect a stressed plant before feeding
When not to fertilize
Sources
- Royal Horticultural SocietyCultivation; Fertilizer; Growing conditions
- North Carolina State University Extension Gardener Plant ToolboxCultural Conditions; Houseplant care