Houseplant Care in May
May is when the choice opens up: keep plants indoors year-round, or move them outside for the warm months. The science is clear on the trade-offs.
Once nights stay above 50°F, you can move tropical plants outside (shaded spot, 1-week acclimation). Indoor plants hit full fertilizer cadence.
Light in May
Most indoor windows now exceed many species’ optimal light range. Diffusing curtains help. Plants moved outside need shaded, not full-sun, acclimation.
Watering in May
Outdoor plants dry 3–5x faster than indoor. Indoor plants are at peak summer schedule.
Pests and problems to watch in May
Outdoor plants are exposed to a new pest ecosystem. UC IPM: quarantine all returning plants for 2 weeks before reintroducing indoors.
What to plan now
Take cuttings of fast-growers (pothos, philodendron, tradescantia) now — propagated plants will be mature by fall.